This document discusses muffler pre-processing methodology using HyperMesh and compares it to CFD tools. It outlines the steps for setting up muffler models in HyperMesh and CFD, including importing CAD geometry, meshing, and defining boundary conditions. Transmission loss results from HyperMesh and CFD muffler models are compared to experimental data to validate the simulation approach. HyperMesh is highlighted as reducing pre-processing time for muffler analysis.
1) The document describes determining the forming limit diagram (FLD) for stainless steel 304 experimentally using hemispherical dome tests and validating it using computer simulation with HyperForm 11.0.
2) Tensile properties were obtained from uniaxial tensile testing and grid-marked samples were dome tested to failure to experimentally generate the FLD. A typical industrial component was also simulated in HyperForm.
3) The results of the experimental and HyperForm FLDs showed good agreement within 12.5% difference, validating the use of computer simulation to predict forming limits. Using HyperForm eliminated material waste and reduced lead times compared to experimental determination.
IRJET-Retina Image Decomposition using Variational Mode DecompositionIRJET Journal
This document describes research applying the variational mode decomposition (VMD) algorithm to decompose retina images. VMD is presented as an improvement over existing empirical mode decomposition methods as it is less sensitive to noise and frequencies. The researchers apply VMD to decompose a retina image into intrinsic mode functions (IMFs) representing different frequency bands. Texture features are extracted from the IMFs and used to classify retina images as healthy or unhealthy, achieving perfect detection. Hardware implementation of the VMD algorithm on an FPGA is also discussed to improve computational speed for potential medical applications in disease diagnosis.
This document summarizes a design project to create a silencer for the exhaust of a Towngas VE75 soil suction machine. It describes the current design of the VE75, including a site visit to Towngas where sound level and airflow data was collected. Analysis of this data showed sound levels from the exhaust reached 90.4 dB. The project aims to reduce this to 75 dB while meeting requirements outlined in a User Requirements Specification, including a maximum length of 2.2m and a cost below $12,275. Prototypes were constructed and tested in labs to evaluate different noise reduction techniques. This led to a final silencer design utilizing soundproofing, sound absorption and a filter, estimated to reduce sound
The document describes a simulation of a mecanum-wheeled vehicle created using MATLAB and Simulink. Mecanum wheels allow omni-directional movement through combinations of wheel rotations. The simulation models the vehicle dynamics using system equations from prior work. Key parameters like wheel angles and vehicle dimensions are input. The simulation calculates wheel velocities and animates the vehicle model moving in different directions by varying wheel torques as inputs.
Case Study Analysis - Muffler Magic Human Resource Management. Basically It is an automobile company and they have done expansion and after doing expansion their profit is decreasing rather than increasing . So we have to give recommendation to HR department to do increment in profit. We have submitted the critical analysis summary and presentation . It is an group report
The document presents a study on the automobile exhaust system conducted by a group of students led by their project coordinator Mr. Dinesh Dubey. It describes the key components of an exhaust system including the exhaust manifold, exhaust pipes, catalytic converter, muffler and tail pipe. The exhaust manifold collects exhaust gases from the engine and funnels them into the exhaust pipes. The catalytic converter converts harmful exhaust pollutants like hydrocarbons, carbon monoxide, and nitrogen oxides into less harmful emissions. The muffler reduces noise from the exhaust gases before they are expelled through the tail pipe. The exhaust system plays an important role in removing waste gases from the engine and reducing vehicle emissions and pollution.
Computational fluid dynamics (CFD) is a numerical method used to analyze and solve fluid flow problems. CFD uses the mathematical equations that govern fluid motion and heat transfer to simulate the behavior of fluids. It provides a comprehensive examination of systems through modeling of velocity, pressure, temperature, and other properties without extensive physical testing. CFD has advantages of being relatively low cost, fast, and able to simulate real conditions. Limitations include accuracy depending on physical models and numerical errors from discretization. CFD is commonly used in engineering applications like aerodynamics, automotive, and electronics design.
This document discusses the design and optimization of an exhaust muffler for automobiles. It begins with an introduction to the main components of an engine exhaust system, including the exhaust manifold, catalytic converter, muffler, and pipes. It then describes the process of designing an exhaust muffler for a Tata Indica turbo diesel engine in CATIA V5 software. This CAD model is analyzed using finite element analysis in NASTRAN to optimize the muffler design. The results show that increasing the thickness of the muffler baffles from 2mm to 3mm increased the muffler's maximum frequency from 359Hz to 381Hz. In conclusion, finite element analysis can be used to modify muffler designs and improve acoustic performance.
1) The document describes determining the forming limit diagram (FLD) for stainless steel 304 experimentally using hemispherical dome tests and validating it using computer simulation with HyperForm 11.0.
2) Tensile properties were obtained from uniaxial tensile testing and grid-marked samples were dome tested to failure to experimentally generate the FLD. A typical industrial component was also simulated in HyperForm.
3) The results of the experimental and HyperForm FLDs showed good agreement within 12.5% difference, validating the use of computer simulation to predict forming limits. Using HyperForm eliminated material waste and reduced lead times compared to experimental determination.
IRJET-Retina Image Decomposition using Variational Mode DecompositionIRJET Journal
This document describes research applying the variational mode decomposition (VMD) algorithm to decompose retina images. VMD is presented as an improvement over existing empirical mode decomposition methods as it is less sensitive to noise and frequencies. The researchers apply VMD to decompose a retina image into intrinsic mode functions (IMFs) representing different frequency bands. Texture features are extracted from the IMFs and used to classify retina images as healthy or unhealthy, achieving perfect detection. Hardware implementation of the VMD algorithm on an FPGA is also discussed to improve computational speed for potential medical applications in disease diagnosis.
This document summarizes a design project to create a silencer for the exhaust of a Towngas VE75 soil suction machine. It describes the current design of the VE75, including a site visit to Towngas where sound level and airflow data was collected. Analysis of this data showed sound levels from the exhaust reached 90.4 dB. The project aims to reduce this to 75 dB while meeting requirements outlined in a User Requirements Specification, including a maximum length of 2.2m and a cost below $12,275. Prototypes were constructed and tested in labs to evaluate different noise reduction techniques. This led to a final silencer design utilizing soundproofing, sound absorption and a filter, estimated to reduce sound
The document describes a simulation of a mecanum-wheeled vehicle created using MATLAB and Simulink. Mecanum wheels allow omni-directional movement through combinations of wheel rotations. The simulation models the vehicle dynamics using system equations from prior work. Key parameters like wheel angles and vehicle dimensions are input. The simulation calculates wheel velocities and animates the vehicle model moving in different directions by varying wheel torques as inputs.
Case Study Analysis - Muffler Magic Human Resource Management. Basically It is an automobile company and they have done expansion and after doing expansion their profit is decreasing rather than increasing . So we have to give recommendation to HR department to do increment in profit. We have submitted the critical analysis summary and presentation . It is an group report
The document presents a study on the automobile exhaust system conducted by a group of students led by their project coordinator Mr. Dinesh Dubey. It describes the key components of an exhaust system including the exhaust manifold, exhaust pipes, catalytic converter, muffler and tail pipe. The exhaust manifold collects exhaust gases from the engine and funnels them into the exhaust pipes. The catalytic converter converts harmful exhaust pollutants like hydrocarbons, carbon monoxide, and nitrogen oxides into less harmful emissions. The muffler reduces noise from the exhaust gases before they are expelled through the tail pipe. The exhaust system plays an important role in removing waste gases from the engine and reducing vehicle emissions and pollution.
Computational fluid dynamics (CFD) is a numerical method used to analyze and solve fluid flow problems. CFD uses the mathematical equations that govern fluid motion and heat transfer to simulate the behavior of fluids. It provides a comprehensive examination of systems through modeling of velocity, pressure, temperature, and other properties without extensive physical testing. CFD has advantages of being relatively low cost, fast, and able to simulate real conditions. Limitations include accuracy depending on physical models and numerical errors from discretization. CFD is commonly used in engineering applications like aerodynamics, automotive, and electronics design.
This document discusses the design and optimization of an exhaust muffler for automobiles. It begins with an introduction to the main components of an engine exhaust system, including the exhaust manifold, catalytic converter, muffler, and pipes. It then describes the process of designing an exhaust muffler for a Tata Indica turbo diesel engine in CATIA V5 software. This CAD model is analyzed using finite element analysis in NASTRAN to optimize the muffler design. The results show that increasing the thickness of the muffler baffles from 2mm to 3mm increased the muffler's maximum frequency from 359Hz to 381Hz. In conclusion, finite element analysis can be used to modify muffler designs and improve acoustic performance.
IRJET- Vibro Acoustic Analysis of Laminated Composite Plate Roof of Car BodyIRJET Journal
This document discusses a vibro-acoustic analysis of a laminated composite plate roof for a car body. A 3D model of a Maruti Swift car is created using CATIA. An acoustic modal analysis is performed to find the resonance frequencies, which are validated against theoretical calculations. Different materials are considered for the car roof to improve acoustic performance and reduce low frequency resonance amplitudes. The analysis is conducted in ANSYS to study how sound pressure levels inside the vehicle are affected by the roof material and shape. Results show the first resonance mode occurs at 79.864Hz in the X-direction, with maximum sound pressure at the rear of the car air cavity.
The document is a project presentation on the design development of a 3-D Turbula mixer. It includes an introduction, literature survey, problem definition, objectives, research methodology, possible outcomes, resources and limitations, and references. The problem is that conventional mixers only rotate in one direction, causing poor mixing. The project aims to design a kinematic linkage that produces a tumbling 3-D motion to thoroughly mix powders and fluids. The methodology involves design, development, analysis, fabrication, and testing of the mixing mechanism. The outcome will be a designed and fabricated mixing machine that improves mixing rate and quality over conventional designs.
Finite element analysis of center pin and bracket of jig fixture assembly ijm...Dr.Vikas Deulgaonkar
The manufacturing industry caters the range of products to satisfy the ever changing market needs.
To overcome the increasing production demands, the industry implies various techniques. We need a technique for
increasing the production of drilling two holes on a Railway Pinion, improve the quality of product and reduce the
operation time. This project aims to design the Jig and Fixture for the same. The 3-dimensional Computer Aided Model
of the components is made using CATIA V5-R21 software. To study the behavior of component, simulation is carried out.
Preprocessing of the CAD model is carried in Hypermesh software. Boundary conditions are applied using physical
situations of the components. Finite element analysis of the components is done, and the results obtained are compared
with the theoretical analysis and also with the available literature. The stresses and deformations are found within desired limits. Using FE analysis, the parts are manufactured and assembled.
This document compares mesh generation and CFD simulation results for a torque converter using HyperMesh and AcuSolve. It describes generating meshes of the torque converter components in HyperMesh and AcuConsole, then simulating the flows using FVM and FEM solvers. The results from both methods are compared to test data. The goal is to determine the most suitable meshing and simulation platform for modeling torque converter performance to reduce time spent on CFD projects.
One of the most important component in mechanical is Gear for the transmission of power with ease and with less friction. Its main aim is to transfer torque from one shaft to other. There are different kinds of gears namely spur gear, helical gears, worm gears etc. Gear drives are used for different kinds of machines like automobiles, metal cutting tools, material handling equipment’s, rolling mills, marine power plants etc. The friction and other losses in this type of power transmission equipment is comparatively very low. In this work a software called “MATLAB†is used to design a Spur Gear. MATLAB is widely used for lot of research purposes for obtaining accurate results and it has got a lot of built in functions which makes it versatile. It is a user friendly one and when executed it ask the inputs and performs the necessary design calculations and gives necessary output values. As computers are used to perform the task of gear design becomes simple, friendly and error free.
This document reviews various methods that have been used to optimize process parameters for fused deposition modeling (FDM), including the Taguchi method and artificial neural networks (ANNs). It summarizes several studies that used Taguchi designs of experiments and analyses to determine the most significant FDM parameters (e.g., layer thickness, orientation, raster width) that influence properties like strength, flexibility, and dimensional accuracy. It also discusses applications of ANNs to predict experimental results and optimize parameters in other manufacturing processes like injection molding and electrical discharge machining. The document concludes that FDM parameter optimization is important for part quality and that Taguchi methods and ANNs are effective tools for design of experiments, analysis, prediction and optimization.
This document reviews rapid prototyping (RP) techniques. It discusses fused deposition modeling (FDM), stereolithography, selective laser sintering, and laminated object manufacturing as common RP methods. The authors analyze spur gear design and stress using different 3D printing materials and finite element analysis software. They 3D print spur gears using FDM with ABS, PLY, and nylon filaments to test load capacity. The document concludes FDM is a lower-cost option suitable for home use, though it has limited material options and less accuracy than other RP methods.
3D Functional Tolerancing And Annotation CATIALeslie Schulte
- Datum A: Cylindrical surface
- Datum B: Planar surface
- Datum C: Planar surface
International Organization For Standardization Rules Number 5459.1981:
Datum Frame Definition
Student Notes:
3D Functional Tolerancing and Annotation
Copyright DASSAULT SYSTEMES 36
Copyright
DASSAULT
SYSTEMES
Different ISO Standards Rules (5/5)
International Organization For Standardization Rules Number 14405.2011:
- Defines the principles of indicating and specifying surface texture in technical product
documentation.
- It specifies the general rules for indicating surface texture in drawings, and gives rules for
specifying surface texture requirements in technical documents such
Optimization of Instrumental Panel to Reduce Traumatic Brain InjuryIRJET Journal
This document summarizes a study that aimed to optimize an instrumental panel design to reduce traumatic brain injury during vehicle impacts. The study used computer modeling and simulation to analyze head impacts on an instrumental panel and evaluate the Head Impact Criteria (HIC) value. For a baseline model, the HIC value exceeded 1000 at one shoot point, indicating a risk of head injury. The design was modified by varying the panel thickness to reduce stiffness at that point. The modified design analysis showed a reduced HIC value below 1000, demonstrating the design was made safer to absorb more energy and better prevent head injuries.
Numerical and Theoretical Analysis for Investigation of Shear strength of A J...ijsrd.com
This document presents a numerical and theoretical analysis of the shear strength of an adhesive joint used in an automotive application. Finite element analysis was conducted using ABAQUS software to determine the shear stresses induced in two adhesive materials joining a brake shoe assembly under an applied torque load. Shear stress values from the finite element analysis were validated using theoretical calculations. The results showed that one of the adhesive materials (Material 2) produced lower shear stresses than the other (Material 1) according to both the numerical and theoretical analyses. The study aimed to determine the optimal adhesive material and joint design to maximize shear strength for the automotive application.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IRJET- Design and Structural Analysis of an Off Road VehicleIRJET Journal
This document describes the iterative design and structural analysis of an off-road vehicle frame. The frame was modeled in CATIA and analyzed in ANSYS to minimize stress concentrations through thickness and geometry modifications. Several impact tests were simulated, and the frame design was iteratively optimized to reduce stresses below safety thresholds. The final optimized frame design demonstrated reduced weight and stresses within allowable limits for all impact scenarios tested.
IRJET -- CFD Analysis of Dual Throat Thrust Vectoring with Chevron NozzleIRJET Journal
This document summarizes a computational fluid dynamics (CFD) analysis of dual throat thrust vectoring with a chevron nozzle. The study models a normal dual throat nozzle and one with chevron cuts at the exit, then compares flow properties like velocity, pressure, and acoustics between the two designs. Results show that the chevron nozzle reduces noise by around 7% while only minimally decreasing velocity and pressure compared to the normal nozzle, indicating it can help reduce noise without significantly impacting thrust vectoring performance.
Power from the burnt gases in the combustion chamber is delivered to the crankshaft through the piston, piston pin and connecting rod. The crankshaft changes reciprocating motion of the piston in cylinder to the rotary motion of the flywheel. Crankshaft is designed for multi cylinder engine and its 3D model is created using modeling software CATIA V5R20.The 3D printer prints the CATIA design layer by layer forming a real object. 3D printing process is derived from inkjet desktop printers in which multiple deposit jets and the printing material, layer by layer derived from the CATIA data. 3D printing significantly challenges mass production processes in the future. This type of printing is predicted to influence industries, like automotive, medical, education, equipment, consumer products industries and various businesses. T. Venkata Ramana | Sagam Kunta Subhash | Sangem Devendra Kumar | Vanga Balakrishna ""Modelling and 3D Printing of Crankshaft"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23224.pdf
Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/23224/modelling-and-3d-printing-of-crankshaft/t-venkata-ramana
Finite Element Analysis and Optimization of Automotive Seat Floor Mounting Br...IRJET Journal
This document discusses finite element analysis and optimization of an automotive seat floor mounting bracket during the metal forming process using LS-DYNA. It analyzes variables like blank holder force, friction coefficient, and die shoulder radius and their effects on formability. Defects occurring during forming are emphasized. The analysis uses LS-DYNA to simulate the deep drawing and stretching processes and optimize the process parameters to achieve defect-free forming. Material models, contact definitions, boundary conditions, and control cards are defined for the simulation. Orthogonal experimental design is used to optimize factors like blank holder force.
This document describes a MATLAB program for designing chain drives. The program takes user-defined inputs like power transmitted, sprocket speeds and loads. It then calculates and displays design parameters like pitch, roller diameter, center distance and number of links. These results are compared to a sample problem from a textbook, showing close matching. The program outputs multiple design options with varying chain strands and pitches. This allows users to select an optimal design based on requirements, operating conditions and cost. Limitations include a limited transmission ratio and speed range, and ISO chain numbers from 6B to 16B.
Midas nfx 2015 software features presentationCyprien Rusu
The document provides an overview of the Total Analysis Solutions software called midas NFX. It includes the following key points:
1) midas NFX provides an integrated environment for finite element analysis from CAD model preparation to results evaluation with automated functions to simplify the workflow.
2) It features both designer and analyst modes for simplified or advanced analysis, along with various pre-processing functions like CAD cleanup, contact definition, and mesh generation.
3) The software offers a large material database, automated functions to update analysis models and transfer conditions when CAD models change, and high performance parallel solvers.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
1) A CFD analysis was conducted of the underhood flow for a Mahindra Trucks and Buses LCV truck to analyze cooling system performance. Recirculation zones were observed that could reduce cooling efficiency.
2) A sealing flap was proposed and simulated, which significantly reduced recirculation and allowed more fresh air to reach the cooling system, improving performance.
3) The simulation identified that 20-30% of air was recirculating during peak operating conditions. Eliminating this recirculation through the sealing flap could improve fuel efficiency by reducing fan duty cycle times.
O os-12 optimization-of_one-piece_injection_molded_mesAnand Kumar Chinni
This document describes the optimization of one-piece injection molded truck cabin components, specifically the lower bunk assembly. The assembly consists of a bunk panel and bulkhead. Topology optimization was used to optimize the bulkhead for mass reduction. Topography optimization was used on the bunk panel to determine an optimal rib pattern. The optimized designs were analyzed and passed acceptance criteria. This optimization-led approach reduced design cycle time compared to traditional trial-and-error methods.
More Related Content
Similar to Cfd fem-08 muffler-pre-processing_methodology_sharada_motors
IRJET- Vibro Acoustic Analysis of Laminated Composite Plate Roof of Car BodyIRJET Journal
This document discusses a vibro-acoustic analysis of a laminated composite plate roof for a car body. A 3D model of a Maruti Swift car is created using CATIA. An acoustic modal analysis is performed to find the resonance frequencies, which are validated against theoretical calculations. Different materials are considered for the car roof to improve acoustic performance and reduce low frequency resonance amplitudes. The analysis is conducted in ANSYS to study how sound pressure levels inside the vehicle are affected by the roof material and shape. Results show the first resonance mode occurs at 79.864Hz in the X-direction, with maximum sound pressure at the rear of the car air cavity.
The document is a project presentation on the design development of a 3-D Turbula mixer. It includes an introduction, literature survey, problem definition, objectives, research methodology, possible outcomes, resources and limitations, and references. The problem is that conventional mixers only rotate in one direction, causing poor mixing. The project aims to design a kinematic linkage that produces a tumbling 3-D motion to thoroughly mix powders and fluids. The methodology involves design, development, analysis, fabrication, and testing of the mixing mechanism. The outcome will be a designed and fabricated mixing machine that improves mixing rate and quality over conventional designs.
Finite element analysis of center pin and bracket of jig fixture assembly ijm...Dr.Vikas Deulgaonkar
The manufacturing industry caters the range of products to satisfy the ever changing market needs.
To overcome the increasing production demands, the industry implies various techniques. We need a technique for
increasing the production of drilling two holes on a Railway Pinion, improve the quality of product and reduce the
operation time. This project aims to design the Jig and Fixture for the same. The 3-dimensional Computer Aided Model
of the components is made using CATIA V5-R21 software. To study the behavior of component, simulation is carried out.
Preprocessing of the CAD model is carried in Hypermesh software. Boundary conditions are applied using physical
situations of the components. Finite element analysis of the components is done, and the results obtained are compared
with the theoretical analysis and also with the available literature. The stresses and deformations are found within desired limits. Using FE analysis, the parts are manufactured and assembled.
This document compares mesh generation and CFD simulation results for a torque converter using HyperMesh and AcuSolve. It describes generating meshes of the torque converter components in HyperMesh and AcuConsole, then simulating the flows using FVM and FEM solvers. The results from both methods are compared to test data. The goal is to determine the most suitable meshing and simulation platform for modeling torque converter performance to reduce time spent on CFD projects.
One of the most important component in mechanical is Gear for the transmission of power with ease and with less friction. Its main aim is to transfer torque from one shaft to other. There are different kinds of gears namely spur gear, helical gears, worm gears etc. Gear drives are used for different kinds of machines like automobiles, metal cutting tools, material handling equipment’s, rolling mills, marine power plants etc. The friction and other losses in this type of power transmission equipment is comparatively very low. In this work a software called “MATLAB†is used to design a Spur Gear. MATLAB is widely used for lot of research purposes for obtaining accurate results and it has got a lot of built in functions which makes it versatile. It is a user friendly one and when executed it ask the inputs and performs the necessary design calculations and gives necessary output values. As computers are used to perform the task of gear design becomes simple, friendly and error free.
This document reviews various methods that have been used to optimize process parameters for fused deposition modeling (FDM), including the Taguchi method and artificial neural networks (ANNs). It summarizes several studies that used Taguchi designs of experiments and analyses to determine the most significant FDM parameters (e.g., layer thickness, orientation, raster width) that influence properties like strength, flexibility, and dimensional accuracy. It also discusses applications of ANNs to predict experimental results and optimize parameters in other manufacturing processes like injection molding and electrical discharge machining. The document concludes that FDM parameter optimization is important for part quality and that Taguchi methods and ANNs are effective tools for design of experiments, analysis, prediction and optimization.
This document reviews rapid prototyping (RP) techniques. It discusses fused deposition modeling (FDM), stereolithography, selective laser sintering, and laminated object manufacturing as common RP methods. The authors analyze spur gear design and stress using different 3D printing materials and finite element analysis software. They 3D print spur gears using FDM with ABS, PLY, and nylon filaments to test load capacity. The document concludes FDM is a lower-cost option suitable for home use, though it has limited material options and less accuracy than other RP methods.
3D Functional Tolerancing And Annotation CATIALeslie Schulte
- Datum A: Cylindrical surface
- Datum B: Planar surface
- Datum C: Planar surface
International Organization For Standardization Rules Number 5459.1981:
Datum Frame Definition
Student Notes:
3D Functional Tolerancing and Annotation
Copyright DASSAULT SYSTEMES 36
Copyright
DASSAULT
SYSTEMES
Different ISO Standards Rules (5/5)
International Organization For Standardization Rules Number 14405.2011:
- Defines the principles of indicating and specifying surface texture in technical product
documentation.
- It specifies the general rules for indicating surface texture in drawings, and gives rules for
specifying surface texture requirements in technical documents such
Optimization of Instrumental Panel to Reduce Traumatic Brain InjuryIRJET Journal
This document summarizes a study that aimed to optimize an instrumental panel design to reduce traumatic brain injury during vehicle impacts. The study used computer modeling and simulation to analyze head impacts on an instrumental panel and evaluate the Head Impact Criteria (HIC) value. For a baseline model, the HIC value exceeded 1000 at one shoot point, indicating a risk of head injury. The design was modified by varying the panel thickness to reduce stiffness at that point. The modified design analysis showed a reduced HIC value below 1000, demonstrating the design was made safer to absorb more energy and better prevent head injuries.
Numerical and Theoretical Analysis for Investigation of Shear strength of A J...ijsrd.com
This document presents a numerical and theoretical analysis of the shear strength of an adhesive joint used in an automotive application. Finite element analysis was conducted using ABAQUS software to determine the shear stresses induced in two adhesive materials joining a brake shoe assembly under an applied torque load. Shear stress values from the finite element analysis were validated using theoretical calculations. The results showed that one of the adhesive materials (Material 2) produced lower shear stresses than the other (Material 1) according to both the numerical and theoretical analyses. The study aimed to determine the optimal adhesive material and joint design to maximize shear strength for the automotive application.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IRJET- Design and Structural Analysis of an Off Road VehicleIRJET Journal
This document describes the iterative design and structural analysis of an off-road vehicle frame. The frame was modeled in CATIA and analyzed in ANSYS to minimize stress concentrations through thickness and geometry modifications. Several impact tests were simulated, and the frame design was iteratively optimized to reduce stresses below safety thresholds. The final optimized frame design demonstrated reduced weight and stresses within allowable limits for all impact scenarios tested.
IRJET -- CFD Analysis of Dual Throat Thrust Vectoring with Chevron NozzleIRJET Journal
This document summarizes a computational fluid dynamics (CFD) analysis of dual throat thrust vectoring with a chevron nozzle. The study models a normal dual throat nozzle and one with chevron cuts at the exit, then compares flow properties like velocity, pressure, and acoustics between the two designs. Results show that the chevron nozzle reduces noise by around 7% while only minimally decreasing velocity and pressure compared to the normal nozzle, indicating it can help reduce noise without significantly impacting thrust vectoring performance.
Power from the burnt gases in the combustion chamber is delivered to the crankshaft through the piston, piston pin and connecting rod. The crankshaft changes reciprocating motion of the piston in cylinder to the rotary motion of the flywheel. Crankshaft is designed for multi cylinder engine and its 3D model is created using modeling software CATIA V5R20.The 3D printer prints the CATIA design layer by layer forming a real object. 3D printing process is derived from inkjet desktop printers in which multiple deposit jets and the printing material, layer by layer derived from the CATIA data. 3D printing significantly challenges mass production processes in the future. This type of printing is predicted to influence industries, like automotive, medical, education, equipment, consumer products industries and various businesses. T. Venkata Ramana | Sagam Kunta Subhash | Sangem Devendra Kumar | Vanga Balakrishna ""Modelling and 3D Printing of Crankshaft"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23224.pdf
Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/23224/modelling-and-3d-printing-of-crankshaft/t-venkata-ramana
Finite Element Analysis and Optimization of Automotive Seat Floor Mounting Br...IRJET Journal
This document discusses finite element analysis and optimization of an automotive seat floor mounting bracket during the metal forming process using LS-DYNA. It analyzes variables like blank holder force, friction coefficient, and die shoulder radius and their effects on formability. Defects occurring during forming are emphasized. The analysis uses LS-DYNA to simulate the deep drawing and stretching processes and optimize the process parameters to achieve defect-free forming. Material models, contact definitions, boundary conditions, and control cards are defined for the simulation. Orthogonal experimental design is used to optimize factors like blank holder force.
This document describes a MATLAB program for designing chain drives. The program takes user-defined inputs like power transmitted, sprocket speeds and loads. It then calculates and displays design parameters like pitch, roller diameter, center distance and number of links. These results are compared to a sample problem from a textbook, showing close matching. The program outputs multiple design options with varying chain strands and pitches. This allows users to select an optimal design based on requirements, operating conditions and cost. Limitations include a limited transmission ratio and speed range, and ISO chain numbers from 6B to 16B.
Midas nfx 2015 software features presentationCyprien Rusu
The document provides an overview of the Total Analysis Solutions software called midas NFX. It includes the following key points:
1) midas NFX provides an integrated environment for finite element analysis from CAD model preparation to results evaluation with automated functions to simplify the workflow.
2) It features both designer and analyst modes for simplified or advanced analysis, along with various pre-processing functions like CAD cleanup, contact definition, and mesh generation.
3) The software offers a large material database, automated functions to update analysis models and transfer conditions when CAD models change, and high performance parallel solvers.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Similar to Cfd fem-08 muffler-pre-processing_methodology_sharada_motors (20)
1) A CFD analysis was conducted of the underhood flow for a Mahindra Trucks and Buses LCV truck to analyze cooling system performance. Recirculation zones were observed that could reduce cooling efficiency.
2) A sealing flap was proposed and simulated, which significantly reduced recirculation and allowed more fresh air to reach the cooling system, improving performance.
3) The simulation identified that 20-30% of air was recirculating during peak operating conditions. Eliminating this recirculation through the sealing flap could improve fuel efficiency by reducing fan duty cycle times.
O os-12 optimization-of_one-piece_injection_molded_mesAnand Kumar Chinni
This document describes the optimization of one-piece injection molded truck cabin components, specifically the lower bunk assembly. The assembly consists of a bunk panel and bulkhead. Topology optimization was used to optimize the bulkhead for mass reduction. Topography optimization was used on the bunk panel to determine an optimal rib pattern. The optimized designs were analyzed and passed acceptance criteria. This optimization-led approach reduced design cycle time compared to traditional trial-and-error methods.
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1. Muffler Pre-Processing Methodology and Comparative Study
Using HyperMesh
Dr. S. Rajadurai Suresh Natarajan N.Manikandan
Head - R&D Asst Manager - CAE Senior Engineer -Product
Sharda Motor Industries Ltd. Sharda Motor Industries Lt., Development
Research and Development
Research and Development Sharda Motor Industries Ltd.
Mahindra World City,
Mahindra World City, Chennai – 603 002, Tamilnadu. Research and Development
Chennai – 603 002,Tamilnadu. Mahindra World City,
Chennai – 603 002, Tamilnadu.
Abbreviations: NVH - Noise, Vibration, Harshness, TL -Transmission loss
Keywords: Exhaust System, Muffler, Resonator, Impedance tube, Glass wool
Abstract
This paper summarizes the Pre-processing methodology of Exhaust system muffler using pre-processing tool HyperMesh for
calculating transmission loss in the muffler. Also pre-processing methodology from CFD tool also explained. The advantages of using
HyperMesh in reducing the pre-processing time are explained in this paper. The transmission loss for particular frequency range i.e. 50 -
1000 Hz from experimental test setup i.e. Impedance tube are correlated with simulation results from 3D simulation tool for the developed
FE model from HyperMesh and CFD tool are compared and explained in detail in this study.
Introduction
Internal combustion engines are typically equipped with an exhaust muffler to suppress the acoustic pulse
generated by the combustion process. A high intensity pressure wave generated by combustion in the engine
cylinder propagates along the exhaust pipe and radiates from the exhaust pipe termination. The pulse repeats
at the firing frequency of the engine which is defined by f=(engine rpm x number of cylinders) /120 for a
four stroke engine. Exhaust mufflers are designed to reduce sound levels at these frequencies. The purpose
of an automotive muffler is to reduce the engine noise emission. If vehicles did not have a muffler, there
would be an unbearable amount of engine exhaust noise in the environment. The exhaust system contributes
32% of the total noise emitted from the vehicle.
Table1: Noise contributors of vehicle
Contributors Engine Exhaust Intake Driveline Fan& Other structural Miscellaneous
radiator components
Noise 21% 32% 14% 14% 6% 10% 3%
Transmission loss
The transmission loss is defined as the ratio between the sound power incident to the muffler (Wi) and the
transmitted sound power (Wt) for the case that there is a reflection free termination on the downstream side.
TL = 10 log (Wi / Wt)
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Simulation Driven Innovation
2. The transmission loss and backpressure are the major considerations in the
design of exhaust system. They are not compromised to each other. If the transmission loss increases, the
backpressure value also increases and it leads to affect the performance of the vehicle.
Figure.1:Transmission loss of a muffler
Pre-processing methodology using CFD tool
Pre-processing for CFD analysis involves the creation of surface meshes and setup of boundary conditions
for thermal analysis and heat transfer modelling. Meshing is a key step to creating accurate model, correct
mesh continuity and mesh density are needed to efficiently compute results and capture the boundary layer
effects. The quality of CFD solution is depending on the quality of the underlying volume mesh.
Basic volume mesh Types
1. Trimmed Mesh
2. Tetrahedral mesh
3. Polyhedral mesh
CFD process flowchart
Initially CFD analysis may be developed by the following steps, they are
Import CAD geometry
(step. file for internal parts identification)
Parts specification
(Specify each internal parts)
Meshing Values
(Base size & Tolerancing)
Contact Prevention
(Welded and joining parts)
Surface Wrapper
(Check mesh quality to repair surface)
Surface Remesh
HyperMesh (Development of Volume mesh i.e. (Tetra mesh)
Figure 2:CFD Pre-processing methodology
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3. CAD geometry:
CAD systems and their geometric representations have been around for quite some time. Almost all CAD
systems have involved into similar representations for their models. One of the most important aspects to
mesh Generation is accessing CAD geometry. CAD systems often use relatively large tolerances on basis to
provide model operations. This approach is referred to as variable tolerances and modelling by different CAD
systems. The use of these large variable tolerances produces gaps and overlaps in the geometry and
topology of the CAD system.
Figure .3: CAD geometry Model
The major issue with CAD geometry access for mesh generation is the need to understand the analysis
requirements. An appropriate mesh and geometry is to be used for meshing. Meshing is a function of the
analysis to be performed and the desired accuracy. There does not exist an optimal mesh independent of the
analysis to be performed. The element shape quality test for good mesh independent of the analysis is to be
performed for the accuracy desired. The appropriate mesh is one, that produces the desired accuracy for the
problem to be solved.
Surface Wrapping:
When preparing a model for a CFD analysis, surfaces need to be closed in order to generate mesh. The
process of surface wrapping typically involves taking poor quality CAD surface, closing holes in geometry,
joining disconnected surfaces, removing interior and overlapping surfaces.
Figure 4: Surface wrapper muffler with internals
Checking the imported surface will allows us to choose a course of action required for generating a volume
mesh.(e.g.) if surface is free from errors and has good quality triangulation, we can directly proceed to volume
mesh generation. But if the surface has errors, then we have to use either manual repair tools or surface
wrapping to fix errors.
Surface Remesher
The surface remesher is used to improve the overall quality of the surface and optimize it for the volume
mesh models. Specific boundaries can also be omitted from the process so that the original triangulation from
the imported mesh can be improved. The surface remesher is typically used for remeshing surfaces produced
by the surface wrapper and STL data as well as improving the surface for the volume mesh. It also aids the
subsurface generator when the prism mesher option is selected.
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Simulation Driven Innovation
4. Figure .5: Surface Remesh muffler model
Volume mesh generation using HyperMesh
Surface mesh or shell mesh developed from CFD tool is imported into HyperMesh as typical solver input file.
The model is checked for free edges and if found any free edges that needs to be corrected manually to
create the muffler with internal components as single volume. For generating tetra mesh, the model should be
a single volume. The volume mesh has been developed with Tetramesh option in HyperMesh and element
quality parameters such as tetra collapse is to be checked. If Glasswool is inserted into middle chamber of
muffler, it should be in a separate collector.
Figure .6: Volume mesh model of muffler from HyperMesh for CFD surface remesh model
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Simulation Driven Innovation
5. LMS Virtual Lab CFD Muffler Model Setup
The complete volume muffler imported to the LMS Virtual Lab work bench, the inputs and measuring
conditions are feed as per the procedure
Figure .7: LMS Virtual Lab Work Bench
Transmission Loss Result Graph(CFD Mesh Muffler)
Figure.8: TL plot for CFD model
Introduction to HyperMesh
Altair Engineering HyperMesh is a commercial Pre-processing tool for most of the FEA and CFD solver
codes. It is used to develop surface, solid and hybrid mesh with 1D, weld, rigid, mass element connections for
different types of geometries. Also it is used to develop various solver specific input deck i.e. defining material
properties, element properties, loads, boundary conditions and solver settings for performing different CAE
analysis such as static linear and Non-linear, modal, thermal, dynamic, buckling, crash, NVH and impact
analysis. With the use of batch meshing, in-built templates and macros, our pre-processing time has been
reduced in order to quickly analyze the products for design modification and optimization. This will reduce the
product development time to minimize the cost and effort.
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Simulation Driven Innovation
6. Pre-processing methodology using HyperMesh
Import CAD geometry
Geometry cleanup and Mid surface Extraction
Merging of baffle surface and pipe weld surface by
trimming operation
Organizing of component collector for perforation surface on pipe
and baffle plate, pipe outer surface and baffle surface
Shell meshing of muffler components
Solid meshing of internal pipes with perforations
Solid meshing of chamber 1, 2 and 3
i.e. endplate1, baffle plate1 with internal
Node set creation for baffle plates and internal
pipes without perforation
3D detaching of pipe outer surface and baffle
surface without holes from solid mesh
Exporting as solver specific input file (.bdf) for
acoustic simulation
Figure.9: HyperMesh Pre-processing methodology
Geometry simplification
CAD model of exhaust muffler is imported into HyperMesh. Geometry cleanup activity such as removing of
unwanted lines, duplicate surfaces, pinholes and small holes has been done. Midsurface extraction of each
components has been done and baffle plate is merged with muffler shell by trim operation. Also all the weld
gap between pipe to end plate, baffle plate are merged to have node-to-node connectivity at the time of shell
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Simulation Driven Innovation
7. meshing. Surface to be created at both ends of the inlet pipe, outlet pipe and
middle pipe to have enclosed volume.
Figure .10: Muffler Geometry simplification With Internals
Perforated Tube;
Perforated tubes in the muffler as used to escape are deliver the hot exhaust gases through the perforation
holes in the tube.The hole diameter and numbr of perforations are calculated as per the muffler volume and
requirment. The perforation need have to proper spacing between the each hole for better performance.Here
perforations are closed with the creation of surfaces and it should be in separate collector.After geometry
simplification,perforation surfaces are to be meshed with shell elements with minimum element length to have
more number of nodes on the surface to achieve proper flow of gases and minimize noise level.
Perforated tube
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Simulation Driven Innovation
8. Perforations
Figure.11: Perforated Tube and Perforations
Perforated Baffle
Figure.12: Perforated Baffle and Perforations
Baffle plates have many design uses in general in different applications. However, If baffles are created to the
pressurized conditions required within our systems design for proper distribution, and flow rate throughout our
system. Many baffles are adjustable and some are fixed. Air noise is something that baffles are used to help
reduces the backpressure during the hot gas passing through the muffler. Perforated baffles are used to
expand the exhaust gases from one room to another room through the use of their perforations. Perforated
and non-perforated baffle plates are merged with muffler shell with the use of trim operation.
Shell meshing
Shell meshing of muffler components such as muffler shell, end plates, baffle plates and internal perforated
pipes are done with shell elements. Perforation surface are meshed and kept as a separate collector. The
muffler assembly meshed model is checked for free edges to achieve enclosed volume. This enclosed
volume is necessary to create the solid or volume mesh.
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Simulation Driven Innovation
9. Figure.13: Shell mesh of muffler with internals and detaching of nodes
Once we complete the shell mesh, the internals and different rooms are split as per the requirements, the
each room should be created as single volume with their respective internals for that the inlet and outlet
openings must be closed for creating tetra mesh.
Solid meshing
Initially internal perforated pipes surfaces are kept as a separate collector in order to have three chambers.
Solid mesh (Tetrahedral elements) is created for each separated internal pipes up to the weld region of baffle
plates and end plates inside the muffler. Once the volume mesh for each internal pipes are completed, the
model is carefully selected for developing the solid mesh for each chamber. Here chamber1 components are
considered as endplate1,internal perforated pipes and baffle plate1 and taken for developing solid mesh.
Similarly chamber2 components as baffle plate1and 2 and internal pipes between baffles considered for
developing solid mesh. Likewise chamber3 components are baffle plate2 and plate2 and internal pipes in
between baffle plate and end plate are taken for creating solid mesh.
Figure.14: Muffler Solid Mesh from HyperMesh with Wireframe Model
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Simulation Driven Innovation
10. Development of FE model for 3D Acoustic solver
After creating solid mesh, node sets are created for baffle plates shell mesh without considering perforation
surface and internal pipes without perforations.3D Detaching of created node sets for baffle plates and
perforated pipes from tetra mesh of each chambers are to be done to have flow of gases in all perforations in
baffle plate and internal pipes. Then the model is finally checked for whether the connectivity has been
removed for baffle plates and internal pipes outer surfaces to verify the process steps.
Finally, the finished model is updated with the required element types and exported as Nastran input file for
importing it into 3D acoustic simulation solver. The cut section view of the model is verified for correction or
proceeds for acoustic simulation to determine the transmission loss inside the muffler.
HyperMesh Muffler Setup in LMS Virtual Lab
Figure15: LMS Virtual Lab Work Bench for HyperMesh model
Figure.16: Transmission Loss Result Graph (HyperMesh Model)
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Simulation Driven Innovation
11. Transmission Loss Measurement from Test Lab
NVH test lab setup used to measure the transmission loss for Muffler/Resonators. the equipment which is
having 2 quarter inch Microphones and 2 half inch microphones and Up stream, Downstream impedance
tube. The transmission loss setup to measure TL by 2 load conditions are i.e.1.Rigid load and 2.Anechoic
Termination. The test set up is shown below,
Figure.17: Schematic Representation of Test Lab Setup
Figure.18: Impedance tube test Setup
Figure.19: Example muffler for TL calculation
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Simulation Driven Innovation
12. Transmission Loss Result Graph (Test Lab)
Figure.20: TL curve for Experimental method
CFD Muffler TL Vs Test Lab TL Comparison Result
Figure.21: TL comparison curve for CFD model Vs Test Lab
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Simulation Driven Innovation
13. HyperMesh TL Vs NVH TL Comparison Result
Figure.22: TL comparison curve for HyperMesh model Vs Test Lab
HyperMesh TL Vs CFD Muffler TL Comparison Result
Figure.23: TL comparison plot for HyperMesh model Vs CFD model
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Simulation Driven Innovation
14. HyperMesh, CFD and NVH Muffler TL Comparison Graph
Figure.24: TL comparison plot for CFD, HyperMesh model Vs Test lab
Results and Discussion
1) In this paper, FE model development of muffler from Altair's Pre-processing tool HyperMesh and CFD tool
for calculating the transmission loss using 3D Acoustic simulation solver has been explained in detail.
2) The transmission loss parameter for muffler assembly calculated from 3D acoustic solver for HyperMesh
model and CFD model are shown in figure23.
3) It has been observed from Transmission loss curve for HyperMesh model is well correlated with CFD
model and also with NVH Lab measurement i.e. Impedance tube. as shown in figure 24.
Benefits Summary
Altair's Pre-processing tool HyperMesh is effectively used to develop FE model of the muffler assembly for
calculating transmission loss in the muffler. Also it is used to develop the volume mesh for the developed CFD
shell model .HyperMesh is also used for surface repair and trimming operation to have nodal connectivity at
the time of meshing.
HyperMesh pre-processing methodology helps in reducing the pre-processing time for muffler assembly with
good quality mesh control and element quality parameters such as minimum element length, tria element
maximum and minimum angles and tetra collapse are achieved properly to get better correlated results of
transmission loss using 3D acoustic simulation solver.
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Simulation Driven Innovation
15. Challenges
The key challenges faced by us that, at the time of volume mesh development for each chamber of muffler,
the components such as internal pipes passing throughout the end plate and baffle plate are considered as
through hole and suppose if any internal pipes are passing through half of the chamber has been considered
as cavity i.e. outer surface of pipe is taken for volume mesh creation.
After the development of tetrameshing of whole muffler assembly, the volume mesh connection for each
perforation on baffle plate and internal pipes has been done by 3D detaching of volume mesh from already
created node sets for baffle plate and perforated pipes without considering holes.
Sometimes, the developed 3D FE model of muffler from HyperMesh is imported into 3D acoustic simulation
tool, internal components of muffler are not visible if we are viewing in wireframe mode or cut section view.
Future Plans
Altair's HyperMesh pre-processing methodology has to be implemented for different kind of muffler assembly
such as glass wool packed muffler ,integrated muffler (in-built catalytic converter),in-built resonator type
mufflers to determine transmission loss in the muffler using 3D acoustic simulation tool to achieve correlated
results with experimental test setup i.e. Impedance tube.
Conclusion
It has been concluded that Transmission loss of muffler for developed FE model from HyperMesh and CFD
tool has been correlated with experimental testing for the particular frequency range i.e. 0 - 1000 Hz.
HyperMesh Pre-processing tool has been effectively utilized to develop the FE model for TL calculation in 3D
acoustic simulation solver and also method for reducing the meshing time has been explained in this paper.
Acknowledgement
The authors would like to thank Jose bright, Gokulraj, Madhan and Ashwini and Sharda Motor R&D team
members for providing constant support through the project.
Reference
1) Steven J.Owen(1996),A Survey of Unstructured Mesh Generation Technology
2) Senesh.K, Balasubramaniam.P, sudhir Kumar.B(1998) HyperMesh Customization to Manage
FEM data For Custom Hybrid Thermal-Deflection Solver
3) CFD software users manual
4) Sandeep Palaksha, Abhijith Balakrishanan(1997) Modelling CFD specific Domain Using HyperMesh
for Display Case used in the Retail Industry
5) Z.Tao and A.F.Seybert " A review at current Techniques for Muffler Transmission loss measurement".
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Simulation Driven Innovation