The document discusses the premature failure of springs used in Indian railway coaches. It provides background on the Indian railway system and the types of springs used in coach suspensions. Finite element analysis is performed on models of closed-end and open-end helical compression springs used in coaches to understand stresses and failure points. The analysis finds von Mises stresses higher than the yield strength of the spring material, indicating failure under the given loads and boundary conditions for both spring types. Resonant frequencies are also identified that could lead to higher amplitudes and failure under dynamic operating conditions. The study aims to help improve spring design and service life for Indian railways.
- The document summarizes inversions of single and double slider crank chains. It discusses the first, second, third, and fourth inversions of a single slider crank chain and their applications.
- It also discusses the crank and slotted quick return mechanism used in shaping machines. It provides the equations to calculate the time ratio of cutting to return strokes.
- Additionally, it discusses inversions of a double slider crank chain including the elliptical trammels, Scotch yoke mechanism, and Oldham's coupling along with examples and applications of each.
This document discusses cams and followers. It begins by defining a cam as a mechanical device that transmits motion to a follower by direct contact. Cams are commonly used in automobile engines to open and close valves. The document then covers terminology used in cams such as base circle, trace point, and pitch curve. It classifies followers based on shape (knife edge, roller, flat faced) and motion (reciprocating, oscillating). Different types of follower motion such as simple harmonic and constant velocity are also described. Several problems are presented involving constructing cam profiles for given follower specifications and motions.
Definition, Use, Types of beariings, Types of Journal bearing, Materials for journal bearing, Failures of journal bearing, Design terms for journal bearing, Types of roller contact bearing, applications of roller contact bearing, Designation of roller contact bearing, Design terms for roller contact bearing, comparison between journal and roller bearings, characteristics of bearings, selection procedure of bearings
Accelerations in Slider Crank mechanismAkshay shah
1. The connecting rod of an engine mechanism has an angular acceleration of 1200 rad/s^2. Using velocity and acceleration diagrams, the acceleration of the connecting rod's center of gravity G is found to be 414 m/s^2, and the angular acceleration of connecting rod AB is 546 rad/s^2.
2. A four-bar linkage is shown with given link lengths and a rotating crank. With the crank at an angle of 60 degrees, velocity and acceleration diagrams are drawn to determine the angular velocity and acceleration of links QR and RS.
Springs are elastic bodies that can be twisted, pulled, or stretched by an applied force and return to their original shape when the force is released. There is physics behind springs in that when stretched or squashed, a spring creates an opposite force to return to its initial position. Springs are manufactured through processes like winding, grinding, calibration, and coating and can be made from materials like steel, titanium, and copper. Common types of springs include helical tension springs, compression springs, torsion springs, leaf springs, and gas springs. Springs are widely used to avoid vibration, apply forces, and control motion in machines.
A chain hoist uses a chain looped around a drum or wheel to lift loads by pulling the chain. Chain hoists are commonly powered electrically and use a system of gears and pulleys to multiply the lifting force applied by the operator or motor. They are widely used in manufacturing and construction settings to lift heavy objects. Modern electric chain hoists can lift loads automatically with the push of a button, simplifying lifting tasks.
This document provides an overview of different types of gears, including spur gears, helical gears, bevel gears, worm gears, and rack and pinion gears. It discusses the key characteristics of each gear type and how they are used to transmit torque between parallel or intersecting shafts. The document also covers gear terminology, equations, involute profiles, pressure angles, and the fundamental law of gearing. It is intended to instruct students on the basics of gears and gear trains.
The document discusses balancing of rotating masses. It defines balancing as restoring a rotor with unbalance to a balanced state by adjusting mass distribution about its axis of rotation. It describes four cases of balancing: a single mass with a single mass in the same plane; a single mass with two masses in different planes; different masses in the same plane; and different masses in different planes. It provides details on balancing a single mass with one or two masses in other planes, including the conditions that must be satisfied. Finally, it mentions analytical and graphical methods can be used to determine the balancing mass magnitude and position.
- The document summarizes inversions of single and double slider crank chains. It discusses the first, second, third, and fourth inversions of a single slider crank chain and their applications.
- It also discusses the crank and slotted quick return mechanism used in shaping machines. It provides the equations to calculate the time ratio of cutting to return strokes.
- Additionally, it discusses inversions of a double slider crank chain including the elliptical trammels, Scotch yoke mechanism, and Oldham's coupling along with examples and applications of each.
This document discusses cams and followers. It begins by defining a cam as a mechanical device that transmits motion to a follower by direct contact. Cams are commonly used in automobile engines to open and close valves. The document then covers terminology used in cams such as base circle, trace point, and pitch curve. It classifies followers based on shape (knife edge, roller, flat faced) and motion (reciprocating, oscillating). Different types of follower motion such as simple harmonic and constant velocity are also described. Several problems are presented involving constructing cam profiles for given follower specifications and motions.
Definition, Use, Types of beariings, Types of Journal bearing, Materials for journal bearing, Failures of journal bearing, Design terms for journal bearing, Types of roller contact bearing, applications of roller contact bearing, Designation of roller contact bearing, Design terms for roller contact bearing, comparison between journal and roller bearings, characteristics of bearings, selection procedure of bearings
Accelerations in Slider Crank mechanismAkshay shah
1. The connecting rod of an engine mechanism has an angular acceleration of 1200 rad/s^2. Using velocity and acceleration diagrams, the acceleration of the connecting rod's center of gravity G is found to be 414 m/s^2, and the angular acceleration of connecting rod AB is 546 rad/s^2.
2. A four-bar linkage is shown with given link lengths and a rotating crank. With the crank at an angle of 60 degrees, velocity and acceleration diagrams are drawn to determine the angular velocity and acceleration of links QR and RS.
Springs are elastic bodies that can be twisted, pulled, or stretched by an applied force and return to their original shape when the force is released. There is physics behind springs in that when stretched or squashed, a spring creates an opposite force to return to its initial position. Springs are manufactured through processes like winding, grinding, calibration, and coating and can be made from materials like steel, titanium, and copper. Common types of springs include helical tension springs, compression springs, torsion springs, leaf springs, and gas springs. Springs are widely used to avoid vibration, apply forces, and control motion in machines.
A chain hoist uses a chain looped around a drum or wheel to lift loads by pulling the chain. Chain hoists are commonly powered electrically and use a system of gears and pulleys to multiply the lifting force applied by the operator or motor. They are widely used in manufacturing and construction settings to lift heavy objects. Modern electric chain hoists can lift loads automatically with the push of a button, simplifying lifting tasks.
This document provides an overview of different types of gears, including spur gears, helical gears, bevel gears, worm gears, and rack and pinion gears. It discusses the key characteristics of each gear type and how they are used to transmit torque between parallel or intersecting shafts. The document also covers gear terminology, equations, involute profiles, pressure angles, and the fundamental law of gearing. It is intended to instruct students on the basics of gears and gear trains.
The document discusses balancing of rotating masses. It defines balancing as restoring a rotor with unbalance to a balanced state by adjusting mass distribution about its axis of rotation. It describes four cases of balancing: a single mass with a single mass in the same plane; a single mass with two masses in different planes; different masses in the same plane; and different masses in different planes. It provides details on balancing a single mass with one or two masses in other planes, including the conditions that must be satisfied. Finally, it mentions analytical and graphical methods can be used to determine the balancing mass magnitude and position.
Dr. Kei Lau is an expert in aerothermodynamics and hypersonic vehicle design. He has extensive experience with theoretical and experimental analysis techniques as well as computational fluid dynamics and thermal analysis. His work has focused on issues like boundary layer transition and thermal protection system design for programs such as the National Aero-Space Plane. High-fidelity simulation tools are needed to reduce uncertainty in hypersonic vehicle design, including computational fluid dynamics, conjugate heat transfer analysis, and finite element structural analysis.
Universal joints allow drive shafts in vehicles to transmit power between non-parallel rotating shafts, like between the transmission and wheels, to allow for suspension movement. They have been used since antiquity based on gimbal designs. Modern universal joints can be made of steel or plastic and are used in many applications where shafts intersect at an angle. They provide advantages like large angular displacement capability but have disadvantages like output speed and acceleration fluctuations depending on the operating angle.
This document provides a final report on the conceptual design, calculations, and justification of a skidded helicopter tug. It includes sections on problem definition, project brief, conceptual design selection, and detailed design calculations. The calculations cover topics such as load calculations on the scissor jack and lead screw, gear and shaft dimensions, bearing selection, and energy losses. The conceptual design process evaluated three concepts and selected a design using a scissor jack, electric motor, remote control, and sliding mesh gearbox. The detailed calculations size components and check that stresses will be below allowable values when lifting the maximum load of 3500kg.
A bearing is a device that supports load and reduces friction between moving parts. There are two main types: plain/slider bearings and rolling/anti-friction bearings. Rolling bearings use balls or rollers to create separation between surfaces and are more commonly used. Common bearing materials include metals, alloys, and some non-metals. Bearings must be properly selected, mounted, lubricated, and maintained to maximize their lifespan and prevent premature failure.
The fluid discharged by the pump is directed to the ‘hydraulic actuator’.Theactuatorconvertthepressureenergyofthefluid into mechanical energy. There are 3 basic type of hydraulic actuator.
• Theactuatorsconvertthefluidpressuretoasuitablelinearor rotary motion.
• Linearmotion–Hydrauliccylinder
• Rotary motion – Hydro motor
• Rotarymotion–Semi-rotaryactuator
KOM - Unit 2 -kinematics of linkage mechanismkarthi keyan
This document discusses kinematics concepts related to linkages and mechanisms. It covers distance and displacement, instantaneous center of rotation, velocity using the instantaneous center method, types and number of instantaneous centers, angular velocity ratio theorem, significance of coincident points including coriolis acceleration, and an overview of kinematic synthesis including stages and types of synthesis problems.
Vibration analysis aims to reduce equipment maintenance costs and downtime by detecting faults. There are two types of vibrations: free vibrations where the energy stays constant and forced vibrations caused by periodic force input. Damping reduces oscillations by dissipating the stored energy. The most common type is viscous damping where resistance from a fluid dissipates energy depending on parameters like relative velocity. Viscous damping uses fluid films between surfaces, with damping resistance proportional to relative velocity. Fluid dashpots use viscous friction to proportionally relate force to velocity in the opposite direction to slow motion. Eddy current damping uses a magnet and non-ferrous metal where motion induces eddy currents providing resistance.
This document discusses kinematics concepts related to linkages and mechanisms. It includes the following:
1) Definitions for kinematic chain, machine, structure, self closed pair, and force closed pair.
2) Explanations and sketches of the Whitworth quick return mechanism, ratchet and pawl mechanism, and toggle mechanism.
3) Calculation of angular velocities and accelerations for a four bar linkage given link lengths and angular velocity of one link.
This document provides an overview of dynamics of machinery and mechanical vibrations. It discusses the following key points in 3 sentences:
The first unit covers force analysis, including rigid body dynamics, equations of motion, inertia forces, D'Alembert's principle, dynamic analysis in reciprocating engines, static force analysis, and cam dynamics. The second unit discusses balancing of rotating and reciprocating masses, including static and dynamic balancing, balancing of single and multi-cylinder engines. The third unit introduces free vibration analysis, including basic features of vibratory systems, single degree of freedom systems, natural frequency, types of damping, and torsional vibration of shaft systems.
1. Bearings are components that allow parts in a machine to move smoothly against each other. There are two main types: sliding bearings which use lubrication between sliding surfaces, and rolling element bearings which use balls or rollers to minimize friction.
2. Thrust bearings are a type of rolling element bearing designed to support high axial loads on a shaft. Common varieties include ball, roller, and tapered roller thrust bearings.
3. Bushings are plain bearings that can be inserted into a housing to provide a bearing surface, and come in solid, split, or clenched designs to accommodate rotation.
This document discusses governors and gyroscopes. It defines governors as automatic speed control mechanisms that use centrifugal or inertia forces to regulate fuel supply and maintain engine speed. Gyroscopes use conservation of angular momentum to maintain orientation. Their applications include navigation, stabilization of vehicles like helicopters, and maintaining direction in tunnel mining. The document also describes how gyroscopes produce gyroscopic couples that affect a ship's motion during turns, pitching, and rolling.
This document discusses the Hyperloop, a proposed new mode of transportation involving high-speed travel in low-pressure tubes. The Hyperloop was proposed by Elon Musk in 2013 and consists of capsules that carry passengers through a tube at speeds up to 700 mph, propelled by linear induction motors. Projects are underway to develop Hyperloop systems between Los Angeles and San Francisco, Chennai and Bengaluru, and in Dubai and the UK. Advantages include fast travel times, low costs, and environmental friendliness, while disadvantages include high initial investment costs and potential safety issues.
Hydraulics is the study of pressurized liquids in mechanical systems. It involves transmitting force from one area to another using an incompressible fluid like oil. Pascal's law states that pressure exerted anywhere in a confined fluid is transmitted equally throughout. A basic hydraulic system includes a reservoir, pump, actuator, and directional control valve. The pump converts mechanical energy to hydraulic energy by pressurizing the fluid. This pressure is then used by actuators like cylinders and motors to do physical work. Filters are used to keep the fluid clean for long component life. Common applications include aircraft landing gears, fuel systems, and flight control surfaces.
The document discusses various types of linkages and mechanisms used in machinery, including:
- Four-bar linkages and their inversions like crank-rocker, double crank, and double rocker mechanisms.
- Slider-crank mechanisms which convert rotary to reciprocal motion, and their inversions.
- Quick-return mechanisms like the drag link and crank and slotted lever types, which provide a slower cutting stroke and faster return stroke.
- Other topics covered include transmission angles in four-bar linkages and the Scotch yoke mechanism.
Study and analysis of convergent Divergent Nozzle Using CFDAkhilendra Akki
This document presents a study analyzing a convergent-divergent nozzle using computational fluid dynamics (CFD). It discusses modeling a convergent-divergent nozzle geometry in ANSYS Fluent, meshing the model, applying boundary conditions, and obtaining results like pressure, velocity, and temperature contours and plots. The objective is to compare cases with different convergent and divergent angles and area ratios to determine the best suitable nozzle design based on calculated flow parameters.
The document discusses different types of pumps. It defines a pump as a device that moves fluids through mechanical action. It then discusses where pumps are used, such as in factories, offices, homes, and power plants. The document classifies pumps based on their power source, either electrical or mechanical. It focuses on centrifugal pumps, describing their parts and working principle of using centrifugal force to pump fluid from the center to the outside of a circle. Advantages and disadvantages of centrifugal pumps are provided. Reciprocating and rotary pumps are also described along with their parts, types, advantages and disadvantages. The document concludes with discussing pump performance curves and defining pump efficiency.
This document discusses various types of hydraulic and pneumatic control elements. It focuses on flow control valves and their purposes.
Flow control valves regulate fluid flow and include pressure control valves, flow control valves, and direction control valves. Pressure control valves such as relief valves and reducing valves maintain system pressure. Flow control valves include compensated and non-compensated types to regulate flow rates. Direction control valves include 2/2, 3/2, and 4/3 styles to control fluid direction to actuators. Proper control elements are necessary to ensure safe and efficient operation of hydraulic and pneumatic systems.
This document describes a proposed multi-server cloud system within a building based on determining the nearest server using the shortest path algorithm. The system has multiple upload stations that act as servers, and client nodes that can be mobile. When a client tries to upload data, the system intelligently finds the nearest upload station based on the client's location and measured signal strength. Data is encrypted during transmission and storage for security. The design includes a client application that allows users to login, access files and more. Data structures like dictionaries and lists are used to store user and file information in text files on the upload stations.
10 اشياء يجب عليك معرفتها قبل إجراء مقابلة التوظيفosmanabdelrhman
مهما كانت سيرتك الذاتية ممتازة واجتهدت فى كتابتها فانك تكون قد قطعت نصف الطريق فقط للحصول على الوظيفة . لذا يجب عليك الاستعداد لاجراء مقابلة التوظيف لتثبت انك كفء للحصول على الوظيفة
Dr. Kei Lau is an expert in aerothermodynamics and hypersonic vehicle design. He has extensive experience with theoretical and experimental analysis techniques as well as computational fluid dynamics and thermal analysis. His work has focused on issues like boundary layer transition and thermal protection system design for programs such as the National Aero-Space Plane. High-fidelity simulation tools are needed to reduce uncertainty in hypersonic vehicle design, including computational fluid dynamics, conjugate heat transfer analysis, and finite element structural analysis.
Universal joints allow drive shafts in vehicles to transmit power between non-parallel rotating shafts, like between the transmission and wheels, to allow for suspension movement. They have been used since antiquity based on gimbal designs. Modern universal joints can be made of steel or plastic and are used in many applications where shafts intersect at an angle. They provide advantages like large angular displacement capability but have disadvantages like output speed and acceleration fluctuations depending on the operating angle.
This document provides a final report on the conceptual design, calculations, and justification of a skidded helicopter tug. It includes sections on problem definition, project brief, conceptual design selection, and detailed design calculations. The calculations cover topics such as load calculations on the scissor jack and lead screw, gear and shaft dimensions, bearing selection, and energy losses. The conceptual design process evaluated three concepts and selected a design using a scissor jack, electric motor, remote control, and sliding mesh gearbox. The detailed calculations size components and check that stresses will be below allowable values when lifting the maximum load of 3500kg.
A bearing is a device that supports load and reduces friction between moving parts. There are two main types: plain/slider bearings and rolling/anti-friction bearings. Rolling bearings use balls or rollers to create separation between surfaces and are more commonly used. Common bearing materials include metals, alloys, and some non-metals. Bearings must be properly selected, mounted, lubricated, and maintained to maximize their lifespan and prevent premature failure.
The fluid discharged by the pump is directed to the ‘hydraulic actuator’.Theactuatorconvertthepressureenergyofthefluid into mechanical energy. There are 3 basic type of hydraulic actuator.
• Theactuatorsconvertthefluidpressuretoasuitablelinearor rotary motion.
• Linearmotion–Hydrauliccylinder
• Rotary motion – Hydro motor
• Rotarymotion–Semi-rotaryactuator
KOM - Unit 2 -kinematics of linkage mechanismkarthi keyan
This document discusses kinematics concepts related to linkages and mechanisms. It covers distance and displacement, instantaneous center of rotation, velocity using the instantaneous center method, types and number of instantaneous centers, angular velocity ratio theorem, significance of coincident points including coriolis acceleration, and an overview of kinematic synthesis including stages and types of synthesis problems.
Vibration analysis aims to reduce equipment maintenance costs and downtime by detecting faults. There are two types of vibrations: free vibrations where the energy stays constant and forced vibrations caused by periodic force input. Damping reduces oscillations by dissipating the stored energy. The most common type is viscous damping where resistance from a fluid dissipates energy depending on parameters like relative velocity. Viscous damping uses fluid films between surfaces, with damping resistance proportional to relative velocity. Fluid dashpots use viscous friction to proportionally relate force to velocity in the opposite direction to slow motion. Eddy current damping uses a magnet and non-ferrous metal where motion induces eddy currents providing resistance.
This document discusses kinematics concepts related to linkages and mechanisms. It includes the following:
1) Definitions for kinematic chain, machine, structure, self closed pair, and force closed pair.
2) Explanations and sketches of the Whitworth quick return mechanism, ratchet and pawl mechanism, and toggle mechanism.
3) Calculation of angular velocities and accelerations for a four bar linkage given link lengths and angular velocity of one link.
This document provides an overview of dynamics of machinery and mechanical vibrations. It discusses the following key points in 3 sentences:
The first unit covers force analysis, including rigid body dynamics, equations of motion, inertia forces, D'Alembert's principle, dynamic analysis in reciprocating engines, static force analysis, and cam dynamics. The second unit discusses balancing of rotating and reciprocating masses, including static and dynamic balancing, balancing of single and multi-cylinder engines. The third unit introduces free vibration analysis, including basic features of vibratory systems, single degree of freedom systems, natural frequency, types of damping, and torsional vibration of shaft systems.
1. Bearings are components that allow parts in a machine to move smoothly against each other. There are two main types: sliding bearings which use lubrication between sliding surfaces, and rolling element bearings which use balls or rollers to minimize friction.
2. Thrust bearings are a type of rolling element bearing designed to support high axial loads on a shaft. Common varieties include ball, roller, and tapered roller thrust bearings.
3. Bushings are plain bearings that can be inserted into a housing to provide a bearing surface, and come in solid, split, or clenched designs to accommodate rotation.
This document discusses governors and gyroscopes. It defines governors as automatic speed control mechanisms that use centrifugal or inertia forces to regulate fuel supply and maintain engine speed. Gyroscopes use conservation of angular momentum to maintain orientation. Their applications include navigation, stabilization of vehicles like helicopters, and maintaining direction in tunnel mining. The document also describes how gyroscopes produce gyroscopic couples that affect a ship's motion during turns, pitching, and rolling.
This document discusses the Hyperloop, a proposed new mode of transportation involving high-speed travel in low-pressure tubes. The Hyperloop was proposed by Elon Musk in 2013 and consists of capsules that carry passengers through a tube at speeds up to 700 mph, propelled by linear induction motors. Projects are underway to develop Hyperloop systems between Los Angeles and San Francisco, Chennai and Bengaluru, and in Dubai and the UK. Advantages include fast travel times, low costs, and environmental friendliness, while disadvantages include high initial investment costs and potential safety issues.
Hydraulics is the study of pressurized liquids in mechanical systems. It involves transmitting force from one area to another using an incompressible fluid like oil. Pascal's law states that pressure exerted anywhere in a confined fluid is transmitted equally throughout. A basic hydraulic system includes a reservoir, pump, actuator, and directional control valve. The pump converts mechanical energy to hydraulic energy by pressurizing the fluid. This pressure is then used by actuators like cylinders and motors to do physical work. Filters are used to keep the fluid clean for long component life. Common applications include aircraft landing gears, fuel systems, and flight control surfaces.
The document discusses various types of linkages and mechanisms used in machinery, including:
- Four-bar linkages and their inversions like crank-rocker, double crank, and double rocker mechanisms.
- Slider-crank mechanisms which convert rotary to reciprocal motion, and their inversions.
- Quick-return mechanisms like the drag link and crank and slotted lever types, which provide a slower cutting stroke and faster return stroke.
- Other topics covered include transmission angles in four-bar linkages and the Scotch yoke mechanism.
Study and analysis of convergent Divergent Nozzle Using CFDAkhilendra Akki
This document presents a study analyzing a convergent-divergent nozzle using computational fluid dynamics (CFD). It discusses modeling a convergent-divergent nozzle geometry in ANSYS Fluent, meshing the model, applying boundary conditions, and obtaining results like pressure, velocity, and temperature contours and plots. The objective is to compare cases with different convergent and divergent angles and area ratios to determine the best suitable nozzle design based on calculated flow parameters.
The document discusses different types of pumps. It defines a pump as a device that moves fluids through mechanical action. It then discusses where pumps are used, such as in factories, offices, homes, and power plants. The document classifies pumps based on their power source, either electrical or mechanical. It focuses on centrifugal pumps, describing their parts and working principle of using centrifugal force to pump fluid from the center to the outside of a circle. Advantages and disadvantages of centrifugal pumps are provided. Reciprocating and rotary pumps are also described along with their parts, types, advantages and disadvantages. The document concludes with discussing pump performance curves and defining pump efficiency.
This document discusses various types of hydraulic and pneumatic control elements. It focuses on flow control valves and their purposes.
Flow control valves regulate fluid flow and include pressure control valves, flow control valves, and direction control valves. Pressure control valves such as relief valves and reducing valves maintain system pressure. Flow control valves include compensated and non-compensated types to regulate flow rates. Direction control valves include 2/2, 3/2, and 4/3 styles to control fluid direction to actuators. Proper control elements are necessary to ensure safe and efficient operation of hydraulic and pneumatic systems.
This document describes a proposed multi-server cloud system within a building based on determining the nearest server using the shortest path algorithm. The system has multiple upload stations that act as servers, and client nodes that can be mobile. When a client tries to upload data, the system intelligently finds the nearest upload station based on the client's location and measured signal strength. Data is encrypted during transmission and storage for security. The design includes a client application that allows users to login, access files and more. Data structures like dictionaries and lists are used to store user and file information in text files on the upload stations.
10 اشياء يجب عليك معرفتها قبل إجراء مقابلة التوظيفosmanabdelrhman
مهما كانت سيرتك الذاتية ممتازة واجتهدت فى كتابتها فانك تكون قد قطعت نصف الطريق فقط للحصول على الوظيفة . لذا يجب عليك الاستعداد لاجراء مقابلة التوظيف لتثبت انك كفء للحصول على الوظيفة
This document summarizes several cluster head selection techniques for mobile ad-hoc networks (MANETs). It begins with an introduction to MANETs and clustering in MANETs. It then surveys 12 different cluster head selection techniques: Lowest ID, Highest Degree, K-hop Connectivity ID, Mobility Based D-hop, Adaptive Cluster Load Balance, Least Cluster Change, Load Balancing, Power-aware Dominant Set, Weighted Approach, Max-Min D-cluster Formation, and Mobility Based Cluster Formation. It provides a brief description of each technique and analyzes their merits and demerits. Finally, it concludes that different techniques select the cluster head based on various parameters like node ID,
This document describes the development of a DC circuit analysis software called CiRSiS using Microsoft Visual C#.Net. The software can analyze purely resistive planar circuits by calculating the current through each component, voltage across each component, and power dissipated by each component. It also displays the direction of current flow. The software was developed using equations, pseudocode, algorithms, flowcharts, and C# code. Test calculations on sample circuits showed the software results matched manual calculations with an average error of 0.339%, demonstrating the reliability of the software for circuit analysis and simulation.
The document outlines an agenda and lesson plan for a teacher training workshop on active learning. The workshop introduces the theory and importance of active learning, provides examples of techniques, and allows time for discussion and activities. Key topics covered include the benefits of engaging students in the learning process through techniques like questioning, group work, and relating material to real-world examples. The goal is for teachers to learn how to develop and apply active learning in their own classrooms.
Andres Eloy Blanco, fue un gran caballero apegado a las causas de libertad y democracia, sus versos eran de inspiración tradicionales y abiertos al pueblo, sus obras fueron editadas en diversos libros, Andres Eloy se destaco en diversas obras como , Giraluna, el huerto de Epopeya, Navegacion de Altura, entre otras. tubo dominio del lenguaje y habilidad para escribir fue un hombre de pensamiento universal, sus versos enaltecieron el sentir venezolano, también se destaco por ser humorista e irónico político.
Andres Eloy Blanco marco la poesía venezolana se preocupo por el país y la visión que le toco vivir para esa época y por otra parte el modernismo que se estaba viviendo, pero tubo siempre criterio de justicia social, por eso vio la política como un camino hacia la justicia social, por eso se decía que Andres Eloy fue un hombre socialista y humanista
DINORAH PAREDES
Profesor: Robert Estanga
Trayecto III. Periodo II
La Unión Europea está considerando nuevas regulaciones para las empresas de tecnología. Estas regulaciones podrían requerir que las grandes compañías tecnológicas compartan datos con los competidores más pequeños y paguen una tasa sobre las ventas. Los críticos argumentan que estas regulaciones podrían dañar la innovación, mientras que los partidarios dicen que podrían promover la competencia en el mercado digital.
Este documento discute a criação de uma maquete para ensinar sobre a Revolução dos Cravos em Portugal em 1974. Ele detalha o planejamento da maquete, incluindo objetivos educacionais, pesquisa necessária e desafios enfrentados, como falta de espaço e tempo. A maquete digital acabou sendo o foco principal para permitir uma investigação mais aprofundada do assunto.
Dr. Norman Amundson presented on using positive affirmation and action-oriented strategies to support career development. He discussed theories of hope, human agency, and protean careers, and introduced an action-oriented, hope-centered career development model. This model uses a Hope-Centered Career Inventory to help clients strengthen competencies like self-reflection, visioning, and adapting. A pilot project applying this with language learners found statistically significant increases in hope and career skills. Follow-up found most participants progressed in their pathways or achieved licensure.
Teranga Gold Corporation is a gold producer and explorer focused on West Africa, with a producing mine in Senegal providing cash flow to fund growth. The company is working to complete a feasibility study and commence construction of its Banfora gold project in Burkina Faso, with anticipated first gold pour in 2019. Teranga has a strong balance sheet with $95 million in cash to fund exploration across Senegal, Burkina Faso, and Côte d'Ivoire, aiming to become the next multi-jurisdictional gold producer in West Africa.
Automation has significantly impacted jobs and the economy over time. While it initially takes away some jobs, it leads to an increase in new types of jobs and a higher overall employment rate. For example, while only 2% of Americans now work on farms compared to 40% in 1900, more people have jobs today. Automation has enabled new industries and more consumer products while increasing leisure time and work-life balance. However, preparing for future automation remains important to ensure new jobs are created that humans are still needed for.
Este documento proporciona información sobre la historia de los Juegos Olímpicos antiguos y modernos. Explica que los antiguos Juegos Olímpicos se realizaban en la antigua Grecia entre los años 776 a.C. y 393 d.C. en honor a los dioses olímpicos. Los Juegos Olímpicos modernos fueron establecidos en 1896 por Pierre de Coubertin y se celebran cada cuatro años en diferentes ciudades del mundo, organizados por el Comité Olímpico Internacional.
Failure analysis of cylinder head valve spring in locomotivesIRJET Journal
This document summarizes a study analyzing the failure of cylinder head valve springs in locomotives. The researchers modeled a coil spring using PRO-E software and analyzed it using ANSYS to simulate different materials, loads, and conditions. They found that heat treatment and proper material selection are important to prevent spring failure from high cycle fatigue. Static structural analysis was performed on models made of chromium vanadium steel and low-carbon steel to determine stresses and optimize material choice. The analysis aims to understand failure mechanisms and improve spring design and quality to avoid premature failures in locomotive engines.
Design and Analysis of A Suspension Coil Spring For Automotive VehicleIJERA Editor
The suspension system is used to observe the vibrations from shock loads due to irregularities of the road
surface. It is perform its function without impairing the stability, steering (or) general handling of the vehicle.
Generally for light vehicles, coil springs are used as suspension system. A spring is an elastic object used to
store mechanical energy and it can be twist, pulled (or) stretched by some force and can return to their original
shape when the force is released. The present work attempts to analyze the safe load of the light vehicle
suspension spring with different materials. This investigation includes comparison of modeling and analyses of
primary suspension spring made of low carbon-structural steel and chrome vanadium steel and suggested the
suitability for optimum design. The results show the reduction in overall stress and deflection of spring for
chosen materials.
IRJET- Static and Dynamic Analysis of a Two Wheeler Shock Absorber using ...IRJET Journal
This document presents a study analyzing the static and dynamic performance of a two-wheeler shock absorber using different materials for the helical coil spring. A 3D model of a shock absorber is created in SolidWorks. Structural, modal, frequency response, and transient analyses are performed to evaluate stresses, displacements, natural frequencies, and dynamic response under various loading conditions. Five different materials - stainless steel, carbon steel, phosphor bronze, beryllium copper, and titanium alloy - are considered for the spring. The analyses aim to determine the best material for the spring to improve the shock absorber's performance.
Modification of a Two Wheeler Suspension System using FeaIJERA Editor
A spring is defined as an elastic body, whose function is to compress when loaded and to recover its original
shape when the load is removed. A spring is a flexible element used to exert a force or a torque and, at the same
time, to store energy. The force can be a linear push or pull, or it can be radial. In two wheelers we used to see
helical suspension at the front and rear tyres on both sides. But the new model bikes are replacing the rear
double suspension with the single heavy duty suspension. Our project deals with the design and modification of
the suspension system and analyzing that can we replace one heavy duty spring in the place of double springs.
For this we have conducted structural analysis by varying the spring material and keeping base material same.
By seeing the results, Comparison is done for four materials to validate better material for suspension system by
doing analysis on spring with help of ANSYS software for find out which material is best for the suspension
system.
And also we modified the actual model and also conducting the same analysis on it and validating that which
model is better.
The modeling done in Creo-5 and analysis is done Ansys package.
Determination of Buckling Loads of Wave Spring Using ANSYSIJRES Journal
Special performance characteristics are individually built into each spring to satisfy a variety of precise operating conditions. Typically, a wave spring will occupy an externally small area for the amount of work it performs. The present work deals with the structural analysis of wave and coil spring by modeling the structural behavior of these springs using three dimensional finite elements (FE) software. The design of spring in suspension system is very important. In this work a wave type of spring is designed and a 3D model is created using CREO software. The model is also varied by changing the length of the spring. Structural analysis has been conducted on the wave spring by varying thickness and number of turns. For the analysis, loads are bike weight with single and two persons. The buckling load is then estimated for both Wave spring and coil spring with the same parameters.
IRJET-Experimental Investigation of Mono Suspension SpringIRJET Journal
The document describes an experimental investigation of a mono suspension spring. A helical compression spring used in the front suspension of a Honda Unicorn motorcycle was tested. A compression test was conducted on the spring for loads between 50-400 kg to determine deflection. Finite element analysis was also performed in ANSYS. Theoretical analysis of spring properties like stress and deformation was carried out and compared to experimental and analytical results. Testing was also done on the shock absorber to determine stresses and transmissibility at different loads and speeds. The research aims to suggest better materials to satisfy design constraints.
This document is a cover sheet and assignment instructions for a student submitting an ANSYS FEA report on stress concentrators in split kayak paddles. The student is analyzing aluminum as an alternative material to composite for kayak paddles. The analyses examines bending, torsion, tension and compression loading on one-piece and split aluminum paddle designs. Experimental data on composite paddles is used for loading conditions. The student aims to minimize additional mass of split aluminum paddles while maintaining performance of composite designs. Tables show the student's iterative analyses to determine optimal wall thicknesses.
Dimensional Optimization of Helical Springs Used in Tractor Seat by FEA and E...IRJET Journal
This document discusses dimensional optimization and failure analysis of helical springs used in tractor seats through finite element analysis (FEA) and experimental testing. It aims to reduce stresses on helical springs under dynamic loading conditions typically experienced in tractor seats.
The study examines the current design of tractor seat helical springs and performs FEA stress analysis, fatigue life analysis, and experimental testing. It also proposes a new spring configuration for the tractor seat to improve spring performance. Results from analytical stress calculations, FEA stress modeling, and experimental fatigue testing of tension and compression springs are presented and compared to evaluate which spring design provides better stress distribution and longer fatigue life.
IRJET- A Review on the Comparison of Helical and Wave SpringsIRJET Journal
1) The document compares helical and wave springs, which are mechanical parts used as shock absorbers. Wave springs have some advantages over helical springs like fitting into tighter spaces and using less material.
2) Several studies on modeling and analyzing helical and wave springs are summarized, examining factors like stress, deflection, fatigue life, buckling load, and damping of vibrations. Finite element analysis is used to model and compare the springs.
3) The objective is to identify the best way to design a helical spring and understand how its design evolved over time to address failure modes, providing insights to counter failures during use. The document reviews analyses of helical and wave springs conducted by other researchers.
Review on Design and Analysis of Two Wheeler Connecting RodIRJET Journal
This document reviews the design and analysis of connecting rods used in two-wheeler engines. It begins with an abstract summarizing the goal of modifying an existing connecting rod design to reduce weight while satisfying design constraints. It then provides a literature review of previous research on connecting rod design and analysis, materials selection, and optimization. This includes analyzing different materials and designs using methods like finite element analysis. The document concludes by stating that most studies found aluminum alloys provided benefits like reduced weight, stress, and strain compared to traditional steel designs.
The document discusses static and fatigue analysis of a modified multi-leaf spring used in light commercial vehicle (LCV) suspension systems. Finite element analysis is performed on the modified 7-leaf steel spring model to analyze stress, deflection, and stiffness. Fatigue life of the modified spring is also predicted using fatigue analysis software. The results from the finite element and fatigue analyses are compared to analytical calculations to validate the model and predicted fatigue life of the modified leaf spring design.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
An Overview of Design and Analysis of Rocker ArmIRJET Journal
This document summarizes research on the design and analysis of rocker arms. It discusses how rocker arms are used to transfer motion from camshafts to engine valves. Finite element analysis is used to model rocker arms and analyze stresses. Different materials are analyzed to reduce stresses and increase durability, including steel, aluminum, composites, and polymers. Studies analyzed stresses on rocker arms made of various materials and identified optimal materials to increase strength while reducing weight. Composite materials showed potential to reduce stresses compared to steel.
Design and Analysis of Helical Spring in Two Wheeler Suspension System using ...IRJET Journal
This document analyzes the design and finite element analysis of helical springs used in the suspension systems of two-wheel vehicles. It discusses modeling a helical spring for a motorcycle in Creo Parametric and analyzing it in ANSYS for stress and deformation. Three spring profiles - circular, square, and square fillet - are analyzed statically and their stresses and displacements are compared. The results show that the square fillet profile experiences lower stresses and deformations compared to the other profiles, indicating it provides better performance for the suspension system. The study aims to optimize helical spring design through analyzing different profiles using finite element analysis.
This document analyzes helical compression springs used in the rear suspension of two-wheeled vehicles. It presents analytical calculations and finite element analysis to determine stresses and deflections in springs made of hard carbon steel and chrome vanadium steel with circular and rectangular cross-sections under various loads. The results show that chrome vanadium steel springs have lower deflections than hard carbon steel springs under the same loads. Chrome vanadium steel is also concluded to be a better replacement material due to its lower cost and ability to work efficiently with less maintenance.
Determination of Fatigue Life of Surface Propeller by Using Finite Element An...sawan kumar
This document summarizes research on modeling and analyzing the fatigue life of a surface propeller using finite element analysis. The propeller was modeled in CATIA and analyzed in ABAQUS to determine stresses and fatigue life. Static structural testing was conducted by varying material properties, and fatigue analysis was performed to analyze the safety factor. Carbon UD/epoxy composite was identified as the best performing material based on the static and fatigue analyses, as it experienced less stress than aluminum. The analyses showed that a composite material propeller would have a longer fatigue life than a metal propeller.
This report details an experiment conducted on a racing car coil spring at the University of Bolton. Measurements were taken of the spring before it was placed on a spring deflection rig. Forces were applied to the spring in increments and the displacement was recorded. A graph of force versus displacement showed a linear relationship. Hysteresis was observed between the experimental readings and calculated displacement at 500kg of force. Coil springs for racing cars must be designed to withstand high weights and are more expensive to produce than springs for normal road cars due to required specifications.
Art of fatigue analysis of helical compression spring used in twoIAEME Publication
This document summarizes research on fatigue analysis of helical compression springs used in two-wheeler horns. It first reviews past literature on spring fatigue analysis and factors affecting spring reliability. It then describes the methodology used for analyzing and enhancing the life of two-wheeler horn springs, which includes obtaining spring specifications, creating CAD models, performing finite element analysis using NASTRAN and fatigue analysis using MSC Fatigue software. The analysis determined the maximum stress in the spring wire based on equations accounting for direct shear stress and torsional shear stress. Experimental testing verified the software results predicted the spring life to be infinite.
Finite element Methods engg Project.pptxhappycocoman
This document summarizes a student project analyzing a helical compression spring using static, modal, and harmonic analysis in FEM. The spring is modeled in Fusion 360 and Ansys Workbench. Static analysis found maximum stress of 8.807e8 Pa and deformation of 0.0269mm under 1667N force. Modal analysis identified the first 8 natural frequencies ranging from 14.54Hz to 193.24Hz. Harmonic analysis from 0.5-80Hz found highest deflection and stress in the inner region. Results showed stresses and deformations within acceptable ranges, and natural frequencies that could cause resonance.
Contact Pressure Validation of Steam Turbine Casing for Static Loading ConditionIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
Similar to The Study of Premature Failure of Springs Used In Railway Coaches (20)
This document provides a technical review of secure banking using RSA and AES encryption methodologies. It discusses how RSA and AES are commonly used encryption standards for secure data transmission between ATMs and bank servers. The document first provides background on ATM security measures and risks of attacks. It then reviews related work analyzing encryption techniques. The document proposes using a one-time password in addition to a PIN for ATM authentication. It concludes that implementing encryption standards like RSA and AES can make transactions more secure and build trust in online banking.
This document analyzes the performance of various modulation schemes for achieving energy efficient communication over fading channels in wireless sensor networks. It finds that for long transmission distances, low-order modulations like BPSK are optimal due to their lower SNR requirements. However, as transmission distance decreases, higher-order modulations like 16-QAM and 64-QAM become more optimal since they can transmit more bits per symbol, outweighing their higher SNR needs. Simulations show lifetime extensions up to 550% are possible in short-range networks by using higher-order modulations instead of just BPSK. The optimal modulation depends on transmission distance and balancing the energy used by electronic components versus power amplifiers.
This document provides a review of mobility management techniques in vehicular ad hoc networks (VANETs). It discusses three modes of communication in VANETs: vehicle-to-infrastructure (V2I), vehicle-to-vehicle (V2V), and hybrid vehicle (HV) communication. For each communication mode, different mobility management schemes are required due to their unique characteristics. The document also discusses mobility management challenges in VANETs and outlines some open research issues in improving mobility management for seamless communication in these dynamic networks.
This document provides a review of different techniques for segmenting brain MRI images to detect tumors. It compares the K-means and Fuzzy C-means clustering algorithms. K-means is an exclusive clustering algorithm that groups data points into distinct clusters, while Fuzzy C-means is an overlapping clustering algorithm that allows data points to belong to multiple clusters. The document finds that Fuzzy C-means requires more time for brain tumor detection compared to other methods like hierarchical clustering or K-means. It also reviews related work applying these clustering algorithms to segment brain MRI images.
1) The document simulates and compares the performance of AODV and DSDV routing protocols in a mobile ad hoc network under three conditions: when users are fixed, when users move towards the base station, and when users move away from the base station.
2) The results show that both protocols have higher packet delivery and lower packet loss when users are either fixed or moving towards the base station, since signal strength is better in those scenarios. Performance degrades when users move away from the base station due to weaker signals.
3) AODV generally has better performance than DSDV, with higher throughput and packet delivery rates observed across the different user mobility conditions.
This document describes the design and implementation of 4-bit QPSK and 256-bit QAM modulation techniques using MATLAB. It compares the two techniques based on SNR, BER, and efficiency. The key steps of implementing each technique in MATLAB are outlined, including generating random bits, modulation, adding noise, and measuring BER. Simulation results show scatter plots and eye diagrams of the modulated signals. A table compares the results, showing that 256-bit QAM provides better performance than 4-bit QPSK. The document concludes that QAM modulation is more effective for digital transmission systems.
The document proposes a hybrid technique using Anisotropic Scale Invariant Feature Transform (A-SIFT) and Robust Ensemble Support Vector Machine (RESVM) to accurately identify faces in images. A-SIFT improves upon traditional SIFT by applying anisotropic scaling to extract richer directional keypoints. Keypoints are processed with RESVM and hypothesis testing to increase accuracy above 95% by repeatedly reprocessing images until the threshold is met. The technique was tested on similar and different facial images and achieved better results than SIFT in retrieval time and reduced keypoints.
This document studies the effects of dielectric superstrate thickness on microstrip patch antenna parameters. Three types of probes-fed patch antennas (rectangular, circular, and square) were designed to operate at 2.4 GHz using Arlondiclad 880 substrate. The antennas were tested with and without an Arlondiclad 880 superstrate of varying thicknesses. It was found that adding a superstrate slightly degraded performance by lowering the resonant frequency and increasing return loss and VSWR, while decreasing bandwidth and gain. Specifically, increasing the superstrate thickness or dielectric constant resulted in greater changes to the antenna parameters.
This document describes a wireless environment monitoring system that utilizes soil energy as a sustainable power source for wireless sensors. The system uses a microbial fuel cell to generate electricity from the microbial activity in soil. Two microbial fuel cells were created using different soil types and various additives to produce different current and voltage outputs. An electronic circuit was designed on a printed circuit board with components like a microcontroller and ZigBee transceiver. Sensors for temperature and humidity were connected to the circuit to monitor the environment wirelessly. The system provides a low-cost way to power remote sensors without needing battery replacement and avoids the high costs of wiring a power source.
1) The document proposes a model for a frequency tunable inverted-F antenna that uses ferrite material.
2) The resonant frequency of the antenna can be significantly shifted from 2.41GHz to 3.15GHz, a 31% shift, by increasing the static magnetic field placed on the ferrite material.
3) Altering the permeability of the ferrite allows tuning of the antenna's resonant frequency without changing the physical dimensions, providing flexibility to operate over a wide frequency range.
This document summarizes a research paper that presents a speech enhancement method using stationary wavelet transform. The method first classifies speech into voiced, unvoiced, and silence regions based on short-time energy. It then applies different thresholding techniques to the wavelet coefficients of each region - modified hard thresholding for voiced speech, semi-soft thresholding for unvoiced speech, and setting coefficients to zero for silence. Experimental results using speech from the TIMIT database corrupted with white Gaussian noise at various SNR levels show improved performance over other popular denoising methods.
This document reviews the design of an energy-optimized wireless sensor node that encrypts data for transmission. It discusses how sensing schemes that group nodes into clusters and transmit aggregated data can reduce energy consumption compared to individual node transmissions. The proposed node design calculates the minimum transmission power needed based on received signal strength and uses a periodic sleep/wake cycle to optimize energy when not sensing or transmitting. It aims to encrypt data at both the node and network level to further optimize energy usage for wireless communication.
This document discusses group consumption modes. It analyzes factors that impact group consumption, including external environmental factors like technological developments enabling new forms of online and offline interactions, as well as internal motivational factors at both the group and individual level. The document then proposes that group consumption modes can be divided into four types based on two dimensions: vertical (group relationship intensity) and horizontal (consumption action period). These four types are instrument-oriented, information-oriented, enjoyment-oriented, and relationship-oriented consumption modes. Finally, the document notes that consumption modes are dynamic and can evolve over time.
The document summarizes a study of different microstrip patch antenna configurations with slotted ground planes. Three antenna designs were proposed and their performance evaluated through simulation: a conventional square patch, an elliptical patch, and a star-shaped patch. All antennas were mounted on an FR4 substrate. The effects of adding different slot patterns to the ground plane on resonance frequency, bandwidth, gain and efficiency were analyzed parametrically. Key findings were that reshaping the patch and adding slots increased bandwidth and shifted resonance frequency. The elliptical and star patches in particular performed better than the conventional design. Three antenna configurations were selected for fabrication and measurement based on the simulations: a conventional patch with a slot under the patch, an elliptical patch with slots
1) The document describes a study conducted to improve call drop rates in a GSM network through RF optimization.
2) Drive testing was performed before and after optimization using TEMS software to record network parameters like RxLevel, RxQuality, and events.
3) Analysis found call drops were occurring due to issues like handover failures between sectors, interference from adjacent channels, and overshooting due to antenna tilt.
4) Corrective actions taken included defining neighbors between sectors, adjusting frequencies to reduce interference, and lowering the mechanical tilt of an antenna.
5) Post-optimization drive testing showed improvements in RxLevel, RxQuality, and a reduction in dropped calls.
This document describes the design of an intelligent autonomous wheeled robot that uses RF transmission for communication. The robot has two modes - automatic mode where it can make its own decisions, and user control mode where a user can control it remotely. It is designed using a microcontroller and can perform tasks like object recognition using computer vision and color detection in MATLAB, as well as wall painting using pneumatic systems. The robot's movement is controlled by DC motors and it uses sensors like ultrasonic sensors and gas sensors to navigate autonomously. RF transmission allows communication between the robot and a remote control unit. The overall aim is to develop a low-cost robotic system for industrial applications like material handling.
This document reviews cryptography techniques to secure the Ad-hoc On-Demand Distance Vector (AODV) routing protocol in mobile ad-hoc networks. It discusses various types of attacks on AODV like impersonation, denial of service, eavesdropping, black hole attacks, wormhole attacks, and Sybil attacks. It then proposes using the RC6 cryptography algorithm to secure AODV by encrypting data packets and detecting and removing malicious nodes launching black hole attacks. Simulation results show that after applying RC6, the packet delivery ratio and throughput of AODV increase while delay decreases, improving the security and performance of the network under attack.
The document describes a proposed modification to the conventional Booth multiplier that aims to increase its speed by applying concepts from Vedic mathematics. Specifically, it utilizes the Urdhva Tiryakbhyam formula to generate all partial products concurrently rather than sequentially. The proposed 8x8 bit multiplier was coded in VHDL, simulated, and found to have a path delay 44.35% lower than a conventional Booth multiplier, demonstrating its potential for higher speed.
This document discusses image deblurring techniques. It begins by introducing image restoration and focusing on image deblurring. It then discusses challenges with image deblurring being an ill-posed problem. It reviews existing approaches to screen image deconvolution including estimating point spread functions and iteratively estimating blur kernels and sharp images. The document also discusses handling spatially variant blur and summarizes the relationship between the proposed method and previous work for different blur types. It proposes using color filters in the aperture to exploit parallax cues for segmentation and blur estimation. Finally, it proposes moving the image sensor circularly during exposure to prevent high frequency attenuation from motion blur.
This document describes modeling an adaptive controller for an aircraft roll control system using PID, fuzzy-PID, and genetic algorithm. It begins by introducing the aircraft roll control system and motivation for developing an adaptive controller to minimize errors from noisy analog sensor signals. It then provides the mathematical model of aircraft roll dynamics and describes modeling the real-time flight control system in MATLAB/Simulink. The document evaluates PID, fuzzy-PID, and PID-GA (genetic algorithm) controllers for aircraft roll control and finds that the PID-GA controller delivers the best performance.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
This document provides basic guidelines for imparitallity requirement of ISO 17025. It defines in detial how it is met and wiudhwdih jdhsjdhwudjwkdbjwkdddddddddddkkkkkkkkkkkkkkkkkkkkkkkwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwioiiiiiiiiiiiii uwwwwwwwwwwwwwwwwhe wiqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq gbbbbbbbbbbbbb owdjjjjjjjjjjjjjjjjjjjj widhi owqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq uwdhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhwqiiiiiiiiiiiiiiiiiiiiiiiiiiiiw0pooooojjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj whhhhhhhhhhh wheeeeeeee wihieiiiiii wihe
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An In-Depth Exploration of Natural Language Processing: Evolution, Applicatio...DharmaBanothu
Natural language processing (NLP) has
recently garnered significant interest for the
computational representation and analysis of human
language. Its applications span multiple domains such
as machine translation, email spam detection,
information extraction, summarization, healthcare,
and question answering. This paper first delineates
four phases by examining various levels of NLP and
components of Natural Language Generation,
followed by a review of the history and progression of
NLP. Subsequently, we delve into the current state of
the art by presenting diverse NLP applications,
contemporary trends, and challenges. Finally, we
discuss some available datasets, models, and
evaluation metrics in NLP.
We have designed & manufacture the Lubi Valves LBF series type of Butterfly Valves for General Utility Water applications as well as for HVAC applications.
A high-Speed Communication System is based on the Design of a Bi-NoC Router, ...DharmaBanothu
The Network on Chip (NoC) has emerged as an effective
solution for intercommunication infrastructure within System on
Chip (SoC) designs, overcoming the limitations of traditional
methods that face significant bottlenecks. However, the complexity
of NoC design presents numerous challenges related to
performance metrics such as scalability, latency, power
consumption, and signal integrity. This project addresses the
issues within the router's memory unit and proposes an enhanced
memory structure. To achieve efficient data transfer, FIFO buffers
are implemented in distributed RAM and virtual channels for
FPGA-based NoC. The project introduces advanced FIFO-based
memory units within the NoC router, assessing their performance
in a Bi-directional NoC (Bi-NoC) configuration. The primary
objective is to reduce the router's workload while enhancing the
FIFO internal structure. To further improve data transfer speed,
a Bi-NoC with a self-configurable intercommunication channel is
suggested. Simulation and synthesis results demonstrate
guaranteed throughput, predictable latency, and equitable
network access, showing significant improvement over previous
designs
Accident detection system project report.pdfKamal Acharya
The Rapid growth of technology and infrastructure has made our lives easier. The
advent of technology has also increased the traffic hazards and the road accidents take place
frequently which causes huge loss of life and property because of the poor emergency facilities.
Many lives could have been saved if emergency service could get accident information and
reach in time. Our project will provide an optimum solution to this draw back. A piezo electric
sensor can be used as a crash or rollover detector of the vehicle during and after a crash. With
signals from a piezo electric sensor, a severe accident can be recognized. According to this
project when a vehicle meets with an accident immediately piezo electric sensor will detect the
signal or if a car rolls over. Then with the help of GSM module and GPS module, the location
will be sent to the emergency contact. Then after conforming the location necessary action will
be taken. If the person meets with a small accident or if there is no serious threat to anyone’s
life, then the alert message can be terminated by the driver by a switch provided in order to
avoid wasting the valuable time of the medical rescue team.
Supermarket Management System Project Report.pdfKamal Acharya
Supermarket management is a stand-alone J2EE using Eclipse Juno program.
This project contains all the necessary required information about maintaining
the supermarket billing system.
The core idea of this project to minimize the paper work and centralize the
data. Here all the communication is taken in secure manner. That is, in this
application the information will be stored in client itself. For further security the
data base is stored in the back-end oracle and so no intruders can access it.
Build the Next Generation of Apps with the Einstein 1 Platform.
Rejoignez Philippe Ozil pour une session de workshops qui vous guidera à travers les détails de la plateforme Einstein 1, l'importance des données pour la création d'applications d'intelligence artificielle et les différents outils et technologies que Salesforce propose pour vous apporter tous les bénéfices de l'IA.
Particle Swarm Optimization–Long Short-Term Memory based Channel Estimation w...IJCNCJournal
Paper Title
Particle Swarm Optimization–Long Short-Term Memory based Channel Estimation with Hybrid Beam Forming Power Transfer in WSN-IoT Applications
Authors
Reginald Jude Sixtus J and Tamilarasi Muthu, Puducherry Technological University, India
Abstract
Non-Orthogonal Multiple Access (NOMA) helps to overcome various difficulties in future technology wireless communications. NOMA, when utilized with millimeter wave multiple-input multiple-output (MIMO) systems, channel estimation becomes extremely difficult. For reaping the benefits of the NOMA and mm-Wave combination, effective channel estimation is required. In this paper, we propose an enhanced particle swarm optimization based long short-term memory estimator network (PSOLSTMEstNet), which is a neural network model that can be employed to forecast the bandwidth required in the mm-Wave MIMO network. The prime advantage of the LSTM is that it has the capability of dynamically adapting to the functioning pattern of fluctuating channel state. The LSTM stage with adaptive coding and modulation enhances the BER.PSO algorithm is employed to optimize input weights of LSTM network. The modified algorithm splits the power by channel condition of every single user. Participants will be first sorted into distinct groups depending upon respective channel conditions, using a hybrid beamforming approach. The network characteristics are fine-estimated using PSO-LSTMEstNet after a rough approximation of channels parameters derived from the received data.
Keywords
Signal to Noise Ratio (SNR), Bit Error Rate (BER), mm-Wave, MIMO, NOMA, deep learning, optimization.
Volume URL: https://airccse.org/journal/ijc2022.html
Abstract URL:https://aircconline.com/abstract/ijcnc/v14n5/14522cnc05.html
Pdf URL: https://aircconline.com/ijcnc/V14N5/14522cnc05.pdf
#scopuspublication #scopusindexed #callforpapers #researchpapers #cfp #researchers #phdstudent #researchScholar #journalpaper #submission #journalsubmission #WBAN #requirements #tailoredtreatment #MACstrategy #enhancedefficiency #protrcal #computing #analysis #wirelessbodyareanetworks #wirelessnetworks
#adhocnetwork #VANETs #OLSRrouting #routing #MPR #nderesidualenergy #korea #cognitiveradionetworks #radionetworks #rendezvoussequence
Here's where you can reach us : ijcnc@airccse.org or ijcnc@aircconline.com
Flow Through Pipe: the analysis of fluid flow within pipesIndrajeet sahu
Flow Through Pipe: This topic covers the analysis of fluid flow within pipes, focusing on laminar and turbulent flow regimes, continuity equation, Bernoulli's equation, Darcy-Weisbach equation, head loss due to friction, and minor losses from fittings and bends. Understanding these principles is crucial for efficient pipe system design and analysis.
Digital Twins Computer Networking Paper Presentation.pptxaryanpankaj78
A Digital Twin in computer networking is a virtual representation of a physical network, used to simulate, analyze, and optimize network performance and reliability. It leverages real-time data to enhance network management, predict issues, and improve decision-making processes.
Prediction of Electrical Energy Efficiency Using Information on Consumer's Ac...PriyankaKilaniya
Energy efficiency has been important since the latter part of the last century. The main object of this survey is to determine the energy efficiency knowledge among consumers. Two separate districts in Bangladesh are selected to conduct the survey on households and showrooms about the energy and seller also. The survey uses the data to find some regression equations from which it is easy to predict energy efficiency knowledge. The data is analyzed and calculated based on five important criteria. The initial target was to find some factors that help predict a person's energy efficiency knowledge. From the survey, it is found that the energy efficiency awareness among the people of our country is very low. Relationships between household energy use behaviors are estimated using a unique dataset of about 40 households and 20 showrooms in Bangladesh's Chapainawabganj and Bagerhat districts. Knowledge of energy consumption and energy efficiency technology options is found to be associated with household use of energy conservation practices. Household characteristics also influence household energy use behavior. Younger household cohorts are more likely to adopt energy-efficient technologies and energy conservation practices and place primary importance on energy saving for environmental reasons. Education also influences attitudes toward energy conservation in Bangladesh. Low-education households indicate they primarily save electricity for the environment while high-education households indicate they are motivated by environmental concerns.
The Study of Premature Failure of Springs Used In Railway Coaches
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 8, Issue 5 (Sep. - Oct. 2013), PP 19-28
www.iosrjournals.org
www.iosrjournals.org 19 | Page
The Study of Premature Failure of Springs Used In Railway
Coaches
M.Sudhakar Reddy1
,B.Madhusudhan Reddy2
(Department Of Mechanical Engineerig, G.Pullareddy Engineerig College (Autonomous) /Jntu Anantapur,
India)
(Department Of Mechanical Engineerig, G.Pulla Reddy Engineerig College (Autonomous) /Jntu Anantapur,
India)
Abstract: The springs used in the bogie suspension of railway coaches are compression springs. They are
made of an elastic wire material formed into the shape of a helix. They are commonly referred to as a coil
spring or a helical spring. They are used to store energy and subsequently release it to absorb shock or to
maintain a force between contact surfaces. The spring returns to its natural length or position when unloaded.
Springs used in railway coaches have been failing prematurely much before their intended service life. The
springs are made with quality materials. Before being put to service, the springs are tested with extensive Non
Destructive Testing Methods which are approved by ISO standards to make sure that quality parts are used.
However the springs still fail before their service life ends.
Keywords: chromium vanadium steel, , helical spring,design constrain , and analysis.
I. Introduction
The Indian railways is one of the largest and busiest rail networks in the world transporting over 18
million passengers and more than 2 million tons of freight daily. With more than 1.4 million employees, it is
known to be the world’s largest commercial or utility employer. This project will involve creating a solid model
of the helical spring using Pro/ENGINEER software with the given specifications and analyzing the same model
using ANSYS software. Here the spring behavior will be observed under prescribed loads to find out if any
stress points exist. Based on this analysis, design recommendations will be made to improve its service life.
II. Methodology
The steps involved in creating a model of the spring. A model of the spring will be first created usign
Pro/Engineer software. Then the model will be imported to ANSYS to complete static and dynamic structural
analysis.
III. Review Of Previous Research Studies
A research study was done on multiaxial fatigue and failure analysis of helical compression springs in
2005. Although uniaxial fatigue analysis has been done in the past, results from multiaxial fatigue analysis are
few. The study is mainly done to see if predicted fatigue life of a spring is different from experimental results.
To estimate the fatigue life of mechanical springs, the study uses different types of criteria and methods to
provide the best results. The fatigue lives are estimated using Fatemi-Socie, Wang-Brown and Coffin-Manson
criteria. These results are then compared with experimental results. A model of the spring is created using
ANSYS software and the stress analysis results are fed into numerical analysis software called nCode. NCode
uses this data to conduct multiaxial fatigue analysis. NCode also predicts the most likely location for the spring
to fail. A failure analysis is also performed to get the exact location of spring failure and compare it with the one
obtained from numerical analysis. The results show different fatigue life predictions for different criteria. “The
Fatemi-Socie critical plane approach gives a good prediction of fatigue life while the Wang-Brown criterion
overestimates fatigue life. Also, the Coffin-Mason model gives very conservative results”. The above results
were obtained from nCode software. It is observed that inner surface of the coil is most susceptible to damage.
This is similar to the one obtained from experimental observation. The results of this study can help determine
the best model to analyze fatigue behavior of a helical compression spring.The results of this study can help
current research investigate if any particular area of the spring experiences more deformation than other areas.
Results will reveal if the top or the bottom coil show more deformation than the rest of the body.
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IV. Mathematical Analysis
4.1 SPRING SPACE
Wire Diameter = 33.5mm
Outer Diameter = 242mm
Inner Diameter = 175mm
No. of coils = 6.75
Free Height = 360mm
Pitch = 53.33
4.2 MATERIAL DATA
Type of steel = Chromium Vanadium Steel - 52Cr4Mo2V
Built to BIS IS: 3195 specifications
Young’s Modulus = 2.068E+11 Pa
Density = 7833.4 kg/m3
a) Stress Concentration factor “k” = 1.264
b) Deflection under 1000 kg “y” = 21.22mm
c) Shear Stress = 832kg/cm2
d) Home stress with "k" = 7465 kg/cm2
e) Modulus of rigidity G = 8155 kg/mm2
4.3 LOADS
A load of 2 MT (metric ton)/19.62 KN is applied on top of the spring.
4.4 BOUNDARY CONDITIONS
The bottom of the spring needs to be fixed i.e. fixed supports.
V. Concept Of Spring Design
The design of a new spring involves the following considerations
• Space into which the spring must fit and operate.
• Values of working forces and deflections.
• Accuracy and reliability needed.
• Tolerances and permissible variations in specifications.
• Environmental conditions such as temperature, presence of a corrosive atmosphere.
• Cost and qualities needed.
The designers use these factors to select a material and specify suitable values for the wire size, the number of
turns, the coil diameter and the free length, type of ends and the spring rate needed to satisfy working force
deflection requirements. The primary design constraints are that the wire size should be commercially available
and that the stress at the solid length be no longer greater than the torsional yield strength.
VI. Method Of Testing Springs
Load testing. The spring is placed on a flat rigid metal support and an incremental increasing load is
applied as specified. Each spring is placed under load for 2 minutes. The height of the spring under this load is
determined and noted. The spring is rejected if “the tolerance on the height of the spring under nominal and
maximum load is more than ±3% of design deflection value at nominal load and ±6% of design deflection value
at maximum load”. Magnetic crack detection test.In this test a spring is “magnetized by current flow along the
axis of the wire”. Current intensity is adjusted based on the dimensions of each spring. Once the current is
passed, the surface of the spring is sprayed with magnetic ink containing Ferro magnetic particles. If a crack
exists in a spring, the Ferro magnetic particles are drawn to the leakage of magnetic field. A black light or an
ultraviolet lamp is used to observe the spring as cracks are now easily visible. The springs are checked for
corrosion and dents manually. Visual inspection is done to see if springs have suffered any damage. If any
corrosion or dents exist, springs are discarded immediately. In chapter two, case studies involving the use of
Ansys software will be examined. Also, types of analysis performed using Ansys software will be explained.
Companies which have used the software to make design improvements to their products will be discussed.
6.1 SPRINGS
All materials to some degree show elastic properties and will deform to some extent when they are
subjected to external loads. “When the load is removed, the material will return to its original shape” without
any deformation provided its elastic limit is not exceeded. A material which shows these properties can be
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considered a spring. Most structures when they are designed will undergo acceptable deformation under
specified loading conditions, but their main requirement is to remain rigid. A spring, however, will store energy
elastically due to its relatively large displacement.
6.2 TYPES OF SPRINGS AND THEIR APPLICATIONS
There are many types of springs available commercially and they come in a variety of shapes and sizes.
They are extensively used in the engineering and industrial fields and are classified by their ability:
1) To absorb or store energy and to mitigate shock and vibration, e.g., buffers, vehicle suspensions, etc.
2) To apply a definite force or torque, e.g., valves, pipe supports, governors, etc.
3) To indicate or control load or torque, e.g., weighing machines, dynamometers, etc.
4) To provide an elastic pivot or guide, e.g., balancing machines, expansion bends, etc.
Different springs can be used for the above functions, but helical springs are usually preferred because of
the following:
1) They show good linear load/deflection characteristics.
2) They have a wide range of movement.
3) They can be made compact, which is important where springs are needed to absorb energy.
One of the important characteristics of helical springs is that their internal friction is very small, so they
return or release a high proportion of any energy stored.
6.3 TYPES OF HELICAL SPRINGS
1) Helical compression springs
2) Helical tension springs
3) Helical torsion springs
4) Conical disc springs
5) Flat or leaf springs
We will be discussing helical compression springs since they are the type of helical spring being examined
in this project.
6.4 HELICAL COMPRESSION SPRINGS
Helical compression springs are usually open coiled and they can resist compressive loads. They are
available in a variety of shapes and sizes and are very widely used. They are usually made from a circular
section material, and their coil diameter remains uniform throughout their length; however, square or
rectangular section materials are also used where space is very limited and are needed to absorb large amount of
energy. Springs which are of the open-ended type are used if axial length is restricted. Springs which have their
ends closed and are ground flat are used more widely because they are able to better distribute the end load. For
this project springs whose ends are closed and ground flat are considered as they are the only type used by
Indian Railways. Springs with plain ground ends are avoided as they become tangled during the manufacturing
process. Springs with ends closed and ground are easy to manufacture and ensure that load distributed will be
axial.
6.5 MATERIALS FOR HELICAL SPRINGS
The materials used in the manufacturing of round wire helical springs are classified below:
1. Patented cold drawn materials – here the mechanical properties required are induced by the drawing
process.
2. Annealed materials – here the required mechanical properties are gained by heat treatment.
Group one type springs are cold formed to the required shape. After they are manufactured, they
require a low temperature stabilizing treatment. They can be sub-divided into the following:
a)Carbon steels
b)Austenitic stainless steels
c) Alloy steels
d) Non-ferrous materials
e) Specials, e.g., titanium alloys
Group two type springs are usually hot formed. They are sub-divided as:
Silicon-manganese steels
a) Chromium-vanadium steels
b) Silicon-manganese steels
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Material is chosen based on its suitability for a particular application. Several factors must be considered
before deciding upon the type of material; these include:
3. Type of loading
4. Static or dynamic
5. Operating temperature and stresses
VII. Analysis On Closed End Spring
The Finite Element Analysis has been carried out for Closed end Mechanical Spring for given operating
conditions. Please refer to Appendix for the design considerations. The spring is simulated using higher order
Solid 92 elements. The geometry model is generated using Pro-E simulation software. The Model is imported to
Ansys to carry Static Analysis followed by the Dynamic Analysis.
7.1 GEOMETRY MODELING
The geometric model developed in Pro-E is shown below
Geometric Model of the Closed End Spring FE Modeling of Closed End Spring with Boundary
Conditions
7.2 STATIC ANALYSIS OF THE CLOSED END SPRING
Displacement of the Spring in UY Direction Displacement of the Spring in USUM Direction
The Vanishes Stress is shown below; the Vanishes stress 1359 Mpa is more than the Yield strength of the
material. The spring may fail for the given loading and boundary conditions
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Vonmises Stress of the Closed End Spring
7.3 MODEL ANALYSIS OF THE CLOSED END SPRING:
The modal analysis is carried out to study the dynamic response of the structure for the given loading
and boundary conditions. The modal analysis outputs the natural frequencies of the structures and its respective
mode shapes. The natural frequencies help to study the operating frequency and its amplitude response
characteristics.
FE Model with Boundary Conditions for Closed End Spring
7.4 NATURAL FREQUENCIES FOR THE CLOSED END SPRING
The natural frequencies of the Closed End Spring is listed below
The First Mode of Natural Frequency: The Second Mode of Natural Frequency:
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First Mode of Natural Frequency Second Mode of Natural Frequency
Resultant Displacement for First Mode Resultant Displacement for Second Mode
of Natural Frequency of Natural Frequency
7.5 HARMONIC ANALYSIS OF THE CLOSED END SPRING:
The Harmonic Analysis is carried to study dynamic behavior of the spring for the given operating
Conditions 0 to 60 Hz. If the spring natural frequency is matches with the operating condition than it amplitudes
shoots up and it will be under resonating conditions.
Displacement in Y direction for Closed End Spring Resultant Displacement for Closed End Spring
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Amplitude Vs Frequency for Closed End Spring Vonmises Stress for Closed End Spring
7.6 STATIC ANALYSIS OF THE OPEN END SPRING
Displacement of the Spring in UY Direction Displacement of the Spring in USUM Direction
Vonmises Stress of the Open End Spring
7.7 MODEL ANALYSIS OF THE OPEN END SPRING:
The modal analysis is carried out to study the dynamic response of the structure for the given loading and
boundary conditions. The modal analysis outputs the natural frequencies of the structures and its respective
mode shapes. The natural frequencies help to study the operating frequency and its amplitude response
characteristics.
7.8 NATURAL FREQUENCIES FOR THE OPEN END SPRING:
The natural frequencies of the Open End Spring is listed below
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The First Mode of Natural Frequency The Second Mode of Natural Frequency
10
Resultant Displacement for First Mode of Resultant Displacement for Second Mode of
Natural Frequency Natural Frequency
7.9 HARMONIC ANALYSIS OF THE OPEN END SPRING
The Harmonic Analysis is carried to study dynamic behavior of the spring for the given operating
Conditions 0 to 60 Hz. If the spring natural frequency is matches with the operating condition than it amplitudes
shoots up and it will be under resonating conditions.
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Displacement in Y direction for Open End Spring Resultant Displacement of Open End Spring
Vonmises Stress for Open End Spring Amplitude Vs. Frequency for Open End Spring
VIII. Results Summary
The Analysis is carried out for Open End Spring and Closed End Spring of the same material for the
given Loading and Boundary Conditions and the results are summarized as below:
The Vonmises Stress for Open End Spring is around 1359 Mpa, Which is more than the Yield Strength of the
material. Hence Material will for the given Loading and Boundary Conditions.
The First Natural Frequency of the Open End Spring is observed as 10 Hz, if it won’t fall near to the operating
frequency. The spring will be safe under dynamic Conditions, or else it will have higher amplitudes and tend to
undergo resonance.
The Vonmises Stress for Open End Spring for Harmonic Analysis is observed as 1107 Mpa, which is more than
the Yield Strength of the Material, Hence design will fail under dynamic operating conditions.
As a general rule, the ratio of Endurance Limit to Ultimate Strength of the Material is 0.6, hence the spring
stress is less than Endurance Limit of the Material, the spring will not have infinite life, and the life of the spring
is less 1e5 Cycles.
For Closed End Spring,
The Vonmises Stress for Closed End Spring is around 1182 Mpa, Which is more than the Yield
Strength of the material. Hence Material will for the given Loading and Boundary Conditions.
The First Natural Frequency of the Closed End Spring is observed as 10 Hz, if it won’t fall near to the operating
frequency. The spring will be safe under dynamic Conditions, or else it will have higher amplitudes and tend to
undergo resonance.
The Vonmises Stress for Closed End Spring for Harmonic Analysis is observed as 1230 Mpa, which is
more than the Yield Strength of the Material, Hence design will fail under dynamic operating conditions.
As a general rule, the ratio of Endurance Limit to Ultimate Strength of the Material is 0.6, hence the spring
stress is less than Endurance Limit of the Material, the spring will not have infinite life, and the life of the spring
is less 1e5 Cycles.
Compare to Open End Spring, Closed end spring will take more loads under given Loading and Operating
Conditions. The Closed End Spring will be better when Compare to Open End Spring.
IX. Conclusion
To study the dynamic behavior of the springs, 3D solid model of helical springs are modeled with PRO/E.
Static and Dynamic stress analysis are carried out using ANSYS to understand the Structural and Dynamic
response of the springs. Spring behavior will be observed under prescribed or expected loads. Based on the
results design modifications will be suggested for better life without failure in service.
X. future Scope
Design optimization can be carried out either by changing material type or changing the design of
spring. The research could throw light on why the springs fail early and why they break only at the inactive coil.
The study could also present suggestions to increase the life of the spring.
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