This document compares two finite element models of a heat exchanger tube-to-tubesheet joint subjected to transient thermal loading. Model I represents tubes as beam elements while Model II represents tubes as spring elements. Both models are analyzed at two time points on the thermal loading curve. Results show that maximum stresses and deformations calculated by the two models are similar, with Model II requiring 38% less computational time. Therefore, using spring elements to model tubes provides a feasible way to determine joint stresses within a reasonable solution time frame for transient thermal-structural analysis of heat exchanger tube-to-tubesheet joints.
EFFECT OF TEMPERATURE IN ANALYSIS OF CREEP IN AN ISOTROPIC UNIFORM COMPOSITE ...ijiert bestjournal
The following paper discusses the effect of tempera ture in analysis of creep in an isotropic uniform composite cylinder. The paper is a part of the series of papers published under the analysis of creep in an isotropic uniform composite cylinder.
Radiator is a device used to cool internal combustion engine by radiating heat out via a fluid called coolant which is being circulated around the engine.
Current generation radiators consist of two header tanks placed on bottom and top interlinked by a passage of tubes, which are flattened in order to maximize the surface area. It is made up of brass or copper soldered to brass headers, but to save money aluminum tubes with plastic headers may also be used.
Pressurized CF 3 I-CO Gas Mixture under Lightning Impulse and its Solid By-P...IJECEIAES
This paper describes tests results on the CF 3 I-CO gas mixtures as an alternative for SF 6 2 gas as to be used as insulating medium in high voltage applications. Pressurized CF 3 I-CO gas mixtures are subject under standard lightning impulse voltages at both positive and negative polarities. Under rod-plane configuration, the electrode gap length and gas pressure are varied accordingly. Upon completion of the laboratory tests, SEM and EDX analyses are carried out to assess the solid by-products. It was found that higher gas mixtures provide better insulation strength. In terms of weight, 50% of the solid by-product is found to be iodine.
Modeling and Thermal Analysis of Disc BrakeIJERA Editor
The disc brake is a device used for slowing or stopping the rotation of the vehicle. Number of times using the brake for vehicle leads to heat generation during braking event, such that disc brake undergoes breakage due to high Temperature. Disc brake model is done by CATIA and analysis is done by using ANSYS workbench. The main purpose of this project is to study the Thermal analysis of the Materials for the Aluminum, Grey Cast Iron, HSS M42, and HSS M2. A comparison between the four materials for the Thermal values and material properties obtained from the Thermal analysis low thermal gradient material is preferred. Hence best suitable design, low thermal gradient material Grey cast iron is preferred for the Disc Brakes for better performance.
A compromise between the temperature difference and performance in a standing...محمود الأمير
Thermoacoustic refrigeration is an evolving cooling technology in which the acoustic power is used to pump heat. The operating conditions and geometric parameters are important for the thermoacoustic refrigerator performance, as they affect both its performance and the temperature difference across the stack. This paper investigates the effect of the stack geometric parameters and operating conditions on the performance of a standing wave thermoacoustic refrigerator and the temperature difference across the stack. DeltaEC software is used to make the thermoacoustic refrigerator model. From the obtained results,
normalised values for the operating conditions and geometric parameters are collected to compromise both the performance and the temperature difference across the stack.
EFFECT OF TEMPERATURE IN ANALYSIS OF CREEP IN AN ISOTROPIC UNIFORM COMPOSITE ...ijiert bestjournal
The following paper discusses the effect of tempera ture in analysis of creep in an isotropic uniform composite cylinder. The paper is a part of the series of papers published under the analysis of creep in an isotropic uniform composite cylinder.
Radiator is a device used to cool internal combustion engine by radiating heat out via a fluid called coolant which is being circulated around the engine.
Current generation radiators consist of two header tanks placed on bottom and top interlinked by a passage of tubes, which are flattened in order to maximize the surface area. It is made up of brass or copper soldered to brass headers, but to save money aluminum tubes with plastic headers may also be used.
Pressurized CF 3 I-CO Gas Mixture under Lightning Impulse and its Solid By-P...IJECEIAES
This paper describes tests results on the CF 3 I-CO gas mixtures as an alternative for SF 6 2 gas as to be used as insulating medium in high voltage applications. Pressurized CF 3 I-CO gas mixtures are subject under standard lightning impulse voltages at both positive and negative polarities. Under rod-plane configuration, the electrode gap length and gas pressure are varied accordingly. Upon completion of the laboratory tests, SEM and EDX analyses are carried out to assess the solid by-products. It was found that higher gas mixtures provide better insulation strength. In terms of weight, 50% of the solid by-product is found to be iodine.
Modeling and Thermal Analysis of Disc BrakeIJERA Editor
The disc brake is a device used for slowing or stopping the rotation of the vehicle. Number of times using the brake for vehicle leads to heat generation during braking event, such that disc brake undergoes breakage due to high Temperature. Disc brake model is done by CATIA and analysis is done by using ANSYS workbench. The main purpose of this project is to study the Thermal analysis of the Materials for the Aluminum, Grey Cast Iron, HSS M42, and HSS M2. A comparison between the four materials for the Thermal values and material properties obtained from the Thermal analysis low thermal gradient material is preferred. Hence best suitable design, low thermal gradient material Grey cast iron is preferred for the Disc Brakes for better performance.
A compromise between the temperature difference and performance in a standing...محمود الأمير
Thermoacoustic refrigeration is an evolving cooling technology in which the acoustic power is used to pump heat. The operating conditions and geometric parameters are important for the thermoacoustic refrigerator performance, as they affect both its performance and the temperature difference across the stack. This paper investigates the effect of the stack geometric parameters and operating conditions on the performance of a standing wave thermoacoustic refrigerator and the temperature difference across the stack. DeltaEC software is used to make the thermoacoustic refrigerator model. From the obtained results,
normalised values for the operating conditions and geometric parameters are collected to compromise both the performance and the temperature difference across the stack.
DESIGN AND TESTING OF STIRLING TYPE COAXIAL PULSE TUBE CRYOCOOLERIAEME Publication
Pulse Tube refrigerators have the potential to be widely applied for producing low temperatures. The most common cryocoolers are either of recuperative or regenerative type. Based on the relative position of regenerator and pulse tube we have various configurations like, inline, ushaped,coaxial and annular. Our area of interest is designing and developing a stirling type, split coaxial pulse tube and suitable linear compressor. The aim is to achieve 80K temperature .The model used for preliminary design is isothermal. Design and fabrication was done in Walchand college and testing was done in Cryogenics lab, IIT, Powai,Mumbai.The results in hand show that the lowest temperature achieved is 94k, with 100W of input power and 92K, with 150W of input power,without any heat load. Exprimental investigations and optimization is done with design and operating parameters. A suitable linear motor compressor, moving coil type is in final stage of manufacturing
Study & Analysis of Knuckle Joint with the Replacement of Material by Using T...IJERA Editor
The rapid growth of technology in recent decades has led to the reduction of cost and weight of materials. The modified system has become popular in industry as well as in research. As a result, this there are reduction in accident and safety has increased. Many systems used in industries use knuckle joint which is combination of two materials: cast iron and stainless steel. Here we are proposing the modification of one of the material that is changing cast iron into a composite polymer material. The proposed system has many advantages over other system such as making the device, simpler and having maximum safety and is ecofriendly. The analysis of the system proves all the above features mention above. The reason for considering polymer is that property of polymer is mostly similar to the property of metal. Composite polymers are characterized by a high flexibility material. The revolutionary evolution in technologies in last year allowed reducing stress and strain. In the present work ANSYS 13 has been used for analysis of knuckle joint with modified material and varying loads.
Structural and Thermal Analysis of Metal - Ceramic Disk BrakeIJSRD
Disk brakes are using from so many years in automotive and still researches are going on in this field for decreasing the temperature effect so that by this we can operate easily. Many new materials are introduced for the disk brake rotor to withstand high temperature produced during braking action. Apart from the high temperature property, the disc rotor materials must also have high thermal conductivity property, as this property decides the amount of heat dissipation to the air stream from the disk rotor. A brake material with good temperature and high thermal conductivity property gives maximum efficiency by overcoming the problem of thermo-mechanical instability [TEI] in the rotor which is more common in low thermal conductivity brake rotor material. In the present work, a Grey cast iron material and metal-ceramic has been chosen for the disk brake rotor. Number of methods before already introduced to know the history of the different materials related to disk brakes, analysis will be done in 2d and 3d in analytical and numerical methods. With different types of assumptions these numerical methods ranges from finite differences to finite elements. To conclude the temperature history for the Grey cast iron material, and metal-ceramic, a numerical simulation technique called finite element method is used. Transient analysis is carried out in ANSYS to predict temperature distribution as a function of time in the disk brake rotor. The results from the transient analysis are compared. As the brake rotor can be treated as the coupled field problem, it is mandatory to do structural analysis after performing thermal analysis in ANSYS to study the stability and rigidity behavior of the rotor material. The results from the transient analysis are given as the input to the structural analysis in order to conclude the stress distribution and displacement in disk brake rotor under thermal loading. The stability behavior of different brake rotor material is compared to facilitate the conceptual design of the disk brake system.
BRAKE DISC ANALYSIS WITH THE HELP OF ANSYS SOFTWAREIAEME Publication
There is lot of upgrade in the technology of the automobile these days. Competition on the speed of vehicles going on in the market. But also this speed leads to accidents if vehicle don’t stop on time. Disc brakes in the vehicles give much better performance compare to drum to stop the vehicle also the heat generated during braking force can be easily dissipated as disc brakes are open to atmosphere. But the main problem is with the material used in the disc brakes in some vehicle. Manufacturers use disc of steel which have short life span and the weight is bulky near the tire.
Study and Experimental Modelling of Welding Parameters on Hardness of Hot Air...IJSRD
The present work has been carried out to study the effect of some input parameters on the desired responses in the Poly Vinyl Chloride (PVC) plastic welding by hot air technique. The effect of hot air temperature, welding speed and air flow rate has been evaluated on the Hardness of the welded joints. These responses have been analysed using the analysis of variance (ANOVA) and experimental modeling. Plots of significant factors and experimental modeling have been used to determine the best fit relationship between the responses and the model parameters using MINITAB 17. This has been used to determine the most influencing parameter.
This Presentation shows the failure analysis of brake disc with help of case study of thermal fatigue cracks of fire fighting brake disc. It also include the component analysis of brake disc. The failure occurs due to the increase in temperature while applying hard braking.
In this paper three different cut patterns of brake disc are studied for heat transfer rate. Heat transfer rate increases with number of cuts in the disc. This is because large area is exposed to air which makes more heat transfer through conduction and convection. But increase in number and size of cuts decreases the strength of disc. And analysed thermally in ANSYS for different material and design created in CREO 3.0.
DETERMINATION OF HEAT TRANSFER COEFFICIENT OF BRAKE ROTOR DISC USING CFD SIMU...IAEME Publication
During engagement of clutches when vehicle is started or during engagement of clutch when vehicle is in motion, the friction clutch generates chatter or also called as Judder vibrations. The vibrational behaviour of friction clutches not only affects the dynamics of transmission system but also the vehicle as result of excitation transfer to body via suspensions and mountings. If excitation level is high then it may cause discomfort to passengers. In addition to those effects vibrations generated may cause wear of friction material and thereby reducing performance and life of clutches.
Thermo-Mechanical Analysis of Automotive Disc Brake Composite Rotorinventionjournals
The heat generated due to friction during braking operation causes several important negative effects on the brake system. It is then important to determine the temperature field of the brake disc. In the present work, a transient thermo-mechanical finite element analysis (FEA) is performed to determine the braking efficiency of a Carbon Ceramic disk brake and compared to a Glass Fiber (S-2) brakes. The aim of the work is to investigate the rise of the temperature of the disk brake under severe braking conditions and the stresses generated from it. The investigation will be done using ANSYS software. ANSYS is a powerful FE package used to determine stress, strain and heat transfer in complicated problems
THERMAL & STRUCTURAL ANALYSIS ON DISC BRAKE ROTOR WITH DRAFTING USING CATIA ...NitinSuryawanshi12
Project consist of two types of analysis thermal , structural & VBA Programming.
Thermal analysis is done to check the thermal resistance of model Honda Unicorn 160.
Structural analysis is done to find the strength of the model.
VBA programming is used to automate drafting task.
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.
DESIGN AND TESTING OF STIRLING TYPE COAXIAL PULSE TUBE CRYOCOOLERIAEME Publication
Pulse Tube refrigerators have the potential to be widely applied for producing low temperatures. The most common cryocoolers are either of recuperative or regenerative type. Based on the relative position of regenerator and pulse tube we have various configurations like, inline, ushaped,coaxial and annular. Our area of interest is designing and developing a stirling type, split coaxial pulse tube and suitable linear compressor. The aim is to achieve 80K temperature .The model used for preliminary design is isothermal. Design and fabrication was done in Walchand college and testing was done in Cryogenics lab, IIT, Powai,Mumbai.The results in hand show that the lowest temperature achieved is 94k, with 100W of input power and 92K, with 150W of input power,without any heat load. Exprimental investigations and optimization is done with design and operating parameters. A suitable linear motor compressor, moving coil type is in final stage of manufacturing
Study & Analysis of Knuckle Joint with the Replacement of Material by Using T...IJERA Editor
The rapid growth of technology in recent decades has led to the reduction of cost and weight of materials. The modified system has become popular in industry as well as in research. As a result, this there are reduction in accident and safety has increased. Many systems used in industries use knuckle joint which is combination of two materials: cast iron and stainless steel. Here we are proposing the modification of one of the material that is changing cast iron into a composite polymer material. The proposed system has many advantages over other system such as making the device, simpler and having maximum safety and is ecofriendly. The analysis of the system proves all the above features mention above. The reason for considering polymer is that property of polymer is mostly similar to the property of metal. Composite polymers are characterized by a high flexibility material. The revolutionary evolution in technologies in last year allowed reducing stress and strain. In the present work ANSYS 13 has been used for analysis of knuckle joint with modified material and varying loads.
Structural and Thermal Analysis of Metal - Ceramic Disk BrakeIJSRD
Disk brakes are using from so many years in automotive and still researches are going on in this field for decreasing the temperature effect so that by this we can operate easily. Many new materials are introduced for the disk brake rotor to withstand high temperature produced during braking action. Apart from the high temperature property, the disc rotor materials must also have high thermal conductivity property, as this property decides the amount of heat dissipation to the air stream from the disk rotor. A brake material with good temperature and high thermal conductivity property gives maximum efficiency by overcoming the problem of thermo-mechanical instability [TEI] in the rotor which is more common in low thermal conductivity brake rotor material. In the present work, a Grey cast iron material and metal-ceramic has been chosen for the disk brake rotor. Number of methods before already introduced to know the history of the different materials related to disk brakes, analysis will be done in 2d and 3d in analytical and numerical methods. With different types of assumptions these numerical methods ranges from finite differences to finite elements. To conclude the temperature history for the Grey cast iron material, and metal-ceramic, a numerical simulation technique called finite element method is used. Transient analysis is carried out in ANSYS to predict temperature distribution as a function of time in the disk brake rotor. The results from the transient analysis are compared. As the brake rotor can be treated as the coupled field problem, it is mandatory to do structural analysis after performing thermal analysis in ANSYS to study the stability and rigidity behavior of the rotor material. The results from the transient analysis are given as the input to the structural analysis in order to conclude the stress distribution and displacement in disk brake rotor under thermal loading. The stability behavior of different brake rotor material is compared to facilitate the conceptual design of the disk brake system.
BRAKE DISC ANALYSIS WITH THE HELP OF ANSYS SOFTWAREIAEME Publication
There is lot of upgrade in the technology of the automobile these days. Competition on the speed of vehicles going on in the market. But also this speed leads to accidents if vehicle don’t stop on time. Disc brakes in the vehicles give much better performance compare to drum to stop the vehicle also the heat generated during braking force can be easily dissipated as disc brakes are open to atmosphere. But the main problem is with the material used in the disc brakes in some vehicle. Manufacturers use disc of steel which have short life span and the weight is bulky near the tire.
Study and Experimental Modelling of Welding Parameters on Hardness of Hot Air...IJSRD
The present work has been carried out to study the effect of some input parameters on the desired responses in the Poly Vinyl Chloride (PVC) plastic welding by hot air technique. The effect of hot air temperature, welding speed and air flow rate has been evaluated on the Hardness of the welded joints. These responses have been analysed using the analysis of variance (ANOVA) and experimental modeling. Plots of significant factors and experimental modeling have been used to determine the best fit relationship between the responses and the model parameters using MINITAB 17. This has been used to determine the most influencing parameter.
This Presentation shows the failure analysis of brake disc with help of case study of thermal fatigue cracks of fire fighting brake disc. It also include the component analysis of brake disc. The failure occurs due to the increase in temperature while applying hard braking.
In this paper three different cut patterns of brake disc are studied for heat transfer rate. Heat transfer rate increases with number of cuts in the disc. This is because large area is exposed to air which makes more heat transfer through conduction and convection. But increase in number and size of cuts decreases the strength of disc. And analysed thermally in ANSYS for different material and design created in CREO 3.0.
DETERMINATION OF HEAT TRANSFER COEFFICIENT OF BRAKE ROTOR DISC USING CFD SIMU...IAEME Publication
During engagement of clutches when vehicle is started or during engagement of clutch when vehicle is in motion, the friction clutch generates chatter or also called as Judder vibrations. The vibrational behaviour of friction clutches not only affects the dynamics of transmission system but also the vehicle as result of excitation transfer to body via suspensions and mountings. If excitation level is high then it may cause discomfort to passengers. In addition to those effects vibrations generated may cause wear of friction material and thereby reducing performance and life of clutches.
Thermo-Mechanical Analysis of Automotive Disc Brake Composite Rotorinventionjournals
The heat generated due to friction during braking operation causes several important negative effects on the brake system. It is then important to determine the temperature field of the brake disc. In the present work, a transient thermo-mechanical finite element analysis (FEA) is performed to determine the braking efficiency of a Carbon Ceramic disk brake and compared to a Glass Fiber (S-2) brakes. The aim of the work is to investigate the rise of the temperature of the disk brake under severe braking conditions and the stresses generated from it. The investigation will be done using ANSYS software. ANSYS is a powerful FE package used to determine stress, strain and heat transfer in complicated problems
THERMAL & STRUCTURAL ANALYSIS ON DISC BRAKE ROTOR WITH DRAFTING USING CATIA ...NitinSuryawanshi12
Project consist of two types of analysis thermal , structural & VBA Programming.
Thermal analysis is done to check the thermal resistance of model Honda Unicorn 160.
Structural analysis is done to find the strength of the model.
VBA programming is used to automate drafting task.
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.
Remaining Life Analysis of Boiler Tubes on Behalf of Hoop Stresses Produced D...IJERA Editor
Boiler tube material plays an important role in efficient power generation from a fossil fuel power plant. In order to meet out the gap between fluids to increase heat available per unit mass flow of steam. Waste heat utilization phenomenon is a big challenge on fossil fuel power plants as after use of high grade coal in thermal power plants the efficiency of power plants is not at the level of required value. Clean and efficient power generation with economical aspects is the basic need of growing power generation plants to justify the quality of power and clean power generation. Life analysis technique to calculate remaining life of boiler tubes at critical zones of high temperature requires much attention and is an important hypothesis in research field. Generation of repetitive and fluctuating stress during flow of high temperature and pressure fluid require proper attention on the methodology to be used to calculate the efficiency of system and absorption efficiency of tube material. In this paper complete mathematical analysis of boiler tubes is conducted for calculation of remaining life of boiler tubes, Hoop stress values are calculated and used with mathematical tool to calculate the efficiency. Hoop stress based calculation of efficiency is more reliable and may give more accurate and practical aspects based results.
QUENCHING CRACK ANALYSIS OF BIG SIZE FORGING BY FE ANALYSISIAEME Publication
Heat treatment crack is one of the main defects of big size forging manufacturing
process. In this research finite element method has been applied to predict crack
initiation by mass effect during water agitation cooling. Cooling curve of specimens
was measured water quenching test and convective coefficients were calculated by
inverse method based on finite element method. Water quenching processes were
analyzed by Deform software and Jmatpro. Crack initiation has been predicted by
comparison of stress distribution and strength on the temperature basis
Fatigue Analysis of Acetylene converter reactorIJMER
The structural integrity of mechanical components during several transients should be
assured in the design stage. This requires a fatigue analysis including thermal and structural analysis. As
an example, this study performs a fatigue analysis of the acetylene converter reactor during arbitrary
transients. Using heat transfer coefficients determined based on the operating environments, a transient
thermal analysis is performed and the results are applied to a finite element model along with the
pressure to calculate the stresses. The total stress intensity range and cumulative fatigue usage factor are
investigated to determine the adequacy of the design
Fatigue Analysis of Acetylene converter reactorIJMER
The structural integrity of mechanical components during several transients should be
assured in the design stage. This requires a fatigue analysis including thermal and structural analysis. As
an example, this study performs a fatigue analysis of the acetylene converter reactor during arbitrary
transients. Using heat transfer coefficients determined based on the operating environments, a transient
thermal analysis is performed and the results are applied to a finite element model along with the
pressure to calculate the stresses. The total stress intensity range and cumulative fatigue usage factor are
investigated to determine the adequacy of the design.
Remaining life assessment of refinery furnace tubes using finite element methodBarhm Mohamad
Crude oil heater 9Cre-1Mo steel tubes from a refinery plant were studied, after 5 years of service at nominally 650 Cº and 3 bar, to predict their remnant lives. The investigation included dimensional, hardness and tensile measurements in addition to accelerated stress rupture tests between 650 Cº and 700 Cº and microstructural examination. Tube specimens were taken from two sections, the overheated side and the side which only saw the nominal operating temperature. The method employed involved the prediction of the increase in temperature with increasing sediment deposition during the operating life times using an FEM model. In addition the predicted temperatures are used to derive appropriate creep properties at relevant temperatures in a 3D pipe FEM creep analysis to predict the pipe deformation rate. All compare well with the actual service exposed pipe measurements and layer deposition. The overheated side revealed a small loss of creep strength in a stress rupture test. A layer of sediment (appr. 10 mm thickness) consisting basically of sintered carbon (coke) spread over the inside of the tube was acting as a thermal barrier causing the temperature to rise above 650 Cº. Analysis for the overheated side predicted an upper bound temperature of 800 Cº and a life of about 50 h suggesting that failure by creep rupture could occur rapidly in the sediment region.
EFFECT OF BAFFLES GEOMETRY ON HEAT TRANSFER ENHANCEMENT INSIDE CORRUGATED DUCTIAEME Publication
The turbulent heat transfer and friction inside a corrugated square duct inserted
with various baffles geometries have been studied experimentally. Five types of baffles
(flat, rectangular, semicircular, triangular and trapezoidal) are attached on top and
bottom walls of the duct. The effects of duct wavy surface, baffle geometry, baffle
position and flow Reynolds number are examined. Air is used as the working fluid
with Reynolds number ranged from 3442.6 to 17213.19 under constant wall heat flux.
Experimental results show obtained for average Nusselt numbers and friction factor.
The results indicate that the trapezoidal baffled geometry provides a higher thermal
performance than the other type baffled one. The present work showed that the highest
thermal performance factor under the same pumping power obtained from the
experiments, is about 2.26 times more than that of plain duct. Also, it is found that the
thermal performance of the baffles attach on the bottom wall of the duct is higher than
the other baffles attach on the top
Effect of Thickness of Tubes on Pressure of Flare
Original Research Article
Journal of Chemistry and Materials Research Vol. 1 (3), 2014, 52–55
M.T. Hannachi *, B. Dahech, H. Guelouche, M. Fareh
THERMAL ANALYSIS OF SHELL AND TUBE TYPE HEAT EXCHANGER TO DEMONSTRATE THE HEA...IAEME Publication
This paper consists of a simplified model of shell and tube type heat exchanger having both interacting mediums as water and steam. In this paper we have first designed a shell and tube heat exchanger to heat water from 40℃ to 70℃ by steam at 140℃ temperature. The design has been done using Kern’s method in order to obtain various dimensions such as shell, tubes, baffles etc. A computer model using CATIA V5 has been developed by using the derived dimensions of heat exchanger. Then the thermal simulation in ANSYS has been performed by applying several thermal loads on different faces and edges. The heat transfer capabilities of several thermal materials have been compared by assigning different materials.
Analysis residual stress e distortions in t joint fillet welds-tso liang teng...ags1963
T-joint ®llet welds are extensively used in ship engineering and bridge structures. Localized heating from the welding process
and subsequent rapid cooling induce tensile residual stress near the toe of the T-joint in ®llet welds.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Generative AI Deep Dive: Advancing from Proof of Concept to ProductionAggregage
Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
Le nuove frontiere dell'AI nell'RPA con UiPath Autopilot™UiPathCommunity
In questo evento online gratuito, organizzato dalla Community Italiana di UiPath, potrai esplorare le nuove funzionalità di Autopilot, il tool che integra l'Intelligenza Artificiale nei processi di sviluppo e utilizzo delle Automazioni.
📕 Vedremo insieme alcuni esempi dell'utilizzo di Autopilot in diversi tool della Suite UiPath:
Autopilot per Studio Web
Autopilot per Studio
Autopilot per Apps
Clipboard AI
GenAI applicata alla Document Understanding
👨🏫👨💻 Speakers:
Stefano Negro, UiPath MVPx3, RPA Tech Lead @ BSP Consultant
Flavio Martinelli, UiPath MVP 2023, Technical Account Manager @UiPath
Andrei Tasca, RPA Solutions Team Lead @NTT Data
SAP Sapphire 2024 - ASUG301 building better apps with SAP Fiori.pdfPeter Spielvogel
Building better applications for business users with SAP Fiori.
• What is SAP Fiori and why it matters to you
• How a better user experience drives measurable business benefits
• How to get started with SAP Fiori today
• How SAP Fiori elements accelerates application development
• How SAP Build Code includes SAP Fiori tools and other generative artificial intelligence capabilities
• How SAP Fiori paves the way for using AI in SAP apps
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
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D012462732
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 4 Ver. VI (Jul. - Aug. 2015), PP 27-32
www.iosrjournals.org
DOI: 10.9790/1684-12462732 www.iosrjournals.org 27 | Page
Stress calculation at tube-to-tubesheet joint using spring model
and its comparison with beam model
Chakradhar.K.Bhande1
, Dattatray.N.Jadhav2
, Sangram.P.Powar3
1
Postgraduate student, Department of Mechanical engineering Sardar Patel College of Engineering, Mumbai,
India.
2
Associate Professor, Department of Mechanical engineering Sardar Patel College of Engineering, Mumbai,
India.
3
Department Head, FEA Department of Ideametrics Private Limited, Pune, India.
Abstract: This paper discuss about evaluation of stresses of tubesheet joint and axial deformation of shell and
tubes of heat exchanger for dewaxing application under transient thermal loading. Two models of tube and
tubesheet, one using tubes as beams and other using tubes as springs has been used to calculate stresses at tube
and tubesheet junction. Axial deformation of shell and induced stresses at tube-to-tubesheet junction obtained
by both models are in close comparison with each other but the computational solution time required for model
with sprigs is almost 38% less than for model with beams.
Keywords: Beam Elements, Spring Rate, Transient Thermal Analysis, Tube-to-Tubesheet Joint.
I. Introduction
Heat exchangers are widely used in process industry. Tubesheet is the main part of the exchanger.
Various researchers in many countries have done a lot of work for the calculation and design of the tubesheet
[1]. Typically, the thicknesses of the shell and the channel in such an exchanger are calculated using the
appropriate codes of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code [2]
and thickness of the tubesheet is usually computed from the formulas given in the Tubular Exchanger
Manufacturers Association (TEMA) Standards [3]. The tube-to-tubesheet joint failure is very common in
industries (refer Fig.1 and Fig.2, figures from web). Therefore, the strength level of the joints has a direct effect
on the safety and the reliability of process plants. The results obtained from experiments and finite element
analyses are presented in different references had mainly focused on the residual stresses, connection strength,
and tightness of expanded joints of tube and tubesheet [4]. The fatigue strength of tube-to-tubesheet welded
joints under cyclic loading was studied by different researchers [4].
The difference in shell side pressure and tube side pressure of heat exchanger will cause the mechanical
stress. Temperature gradient exists widely between tube side as well as shell side. Therefore, there may be high
thermal stress due to the high temperature difference in shell-side and tube-side. The thermal stress has great
impact on the total stress distribution [5]. So the simulation of the temperature field is very important. By means
of thermal analysis coupling with structure analysis, the distribution of temperature, stress and deformation is
obtained. As tubes-and-tubesheet are very heavy components for FEA modeling, hence to simplify them for
ease of solving within more reasonable time frame for analysis, tubes can be replaced by different kind of
elements like bars, beams, pipe etc. [6].
Fig. 1: tube-to-tubesheet failure leads to leakage Fig. 2: tube-to-tubesheet failure from tube inside
2. Stress calculation at tube-to-tubesheet joint using spring model and its comparison with beam model
DOI: 10.9790/1684-12462732 www.iosrjournals.org 28 | Page
II. Design Parameters
2.1 Loading Histogram:
The Heat Exchanger for Dewaxing application leads to transient thermal loading during its application,
the detailed loading histogram is as per graph shown in Fig.3.
Fig. 3: thermal loading histogram for dewaxing heat exchanger [10]
2.1.1 Process Flow of Dewaxing Application [10]:
Details for dewaxing process is-
1. Heating (3Hrs): 20000 kg/h cooling medium, Inlet temperature 52°C, Outlet temperature 56.5 - 150 °C, with
maximum temperature gradient of 0.5 °C/min.
2. Remelt (1.5Hrs): 20000 kg/h cooling medium, Inlet temperature 56.5°C, Outlet temperature 150 °C.
3. Cooling (3Hrs): 20000 kg/h cooling medium, Inlet temperature 56.5°C, Outlet temperature 150 –56.5°C,
with maximum temperature gradient of 0.5 °C/min.
4. Stand-by (0.5Hrs): 20000 kg/h cooling medium, Inlet temperature 56.5°C, Outlet temperature 56.5 °C. No
heating
5. Shell side maximum temperature is 175°C.
6. Shell side constant pressure is 1.6965 MPa and tube side constant pressure is 1.9024 MPa.
2.2 Overall geometry parameters:
Overall geometry parameters of dewaxing heat exchanger are given in Table 1.
Table 1. Overall geometry parameters of dewaxing heat exchanger [10]
Sr. No Shell ID Unit Value
1 Shell Thickness mm 7
2 Tubesheet Ref face to Face Distance mm 2470
3 Overall Length mm 3520
4 Corrosion Allowance (Shell Side/Tube Side) mm 3/3 (0 on tubes)
5 Tubes (Number/OD/thickness/length) mm 202/19.5/2.3/2500
6 Tubes (pitch/pattern) mm 23.81/ ∆
2.3 Material properties:
Material properties for individual components subjected to temperature, are taken from ASME section
II, Part D [7]. Material properties considered for coupled transient thermal and structural analysis are given in
Table 2.
Table 2. Material properties with respect to temperature [7]
Shell, Channels, Dish Ends- SA 516 Gr 70
Tubesheet- SA 266 Gr 2
Tubes- SA 210 Gr A1
Thermal conductivity Coefficient of thermal expansion Young’s Modulus
Temp
(°C)
TC
(W/m °C)
Temp
(°C)
TE
(mm/mm/°C)
Temp
(°C)
E (MPa)
20 60.4 20 1.15E-05 25 202E3
50 59.8 50 1.18E-05 100 198E3
75 58.9 75 1.19E-05 150 195E3
100 58 100 1.21E-05 200 192E3
125 57 125 1.23E-05 250 189E3
150 55.9 150 1.24E-05 300 185E3
3. Stress calculation at tube-to-tubesheet joint using spring model and its comparison with beam model
DOI: 10.9790/1684-12462732 www.iosrjournals.org 29 | Page
175 54.7 175 1.26E-05 350 179E3
200 53.6 200 1.27E-05 400 171E3
III. Finite Element Analysis
3.1 Methodology:
Heat exchanger is subjected to transient thermal loading, thermal loading is considered as per the
loading histogram shown in Fig.3, two static structural analyses has been carried out at two governing points on
loading histogram using results from transient thermal analysis, one at Instance A and other at instance B (refer
Fig.3). Instance A is a point where heating cycle completes at time t=3Hrs and instance B is end of cooling cycle
at time t=7Hrs.
In order to simplify tube-to-tubesheet model for FEA, tubes can be replaced by different kind of
elements like bars, beams, pipe etc. [6]. This will significantly reduce the number of elements and allow the
model to mesh and solve in a more reasonable time frame. Two different models of tubes and tubesheet one using
tubes as beams and other using tubes as springs are used to calculate maximum stresses at tube and tubesheet
junction.
3.2 Finite Element Model (Model 1)
Model I include both tubesheet with six numbers of solid tubes i.e. one solid tube from each pass and
remaining tubes as beam elements are used to represent actual interaction between tube and tubesheet. Fig.4
shows the section view of FEA model I of tube and tubesheet with beams.
3.2.1 Loading and Boundary condition: Temperature is applied on channel side face of tubesheet as well as
solid tubes considered. Tube side thermal loads from first pass through exit of six pass is calculated by linear
interpolation between 1st pass compartment at 52°C and exit of sixth pass at 150°C. Shell side constant
temperature of 180°C is applied on internal faces of shell, tubesheet as well as outer faces of solid tubes. Effect
of insulation is modeled in this analysis by giving equivalent heat transfer coefficient [8]. Thermal loadings
applied to model I are shown in Fig.5.
Fig. 4: FE model with beams- section view Fig. 5: thermal loading conditions for model I
Results of transient thermal analysis are coupled with mechanical loadings which include pressure on
shell side and pressure on tube side along with bolt operating load (Wm1) and gasket seating load (Wm2) on
tubesheet. Bottom face of left saddle is fixed while right saddle has frictionless support. Bolt loads are calculated
using following equations.
Operating Load, Wm1= (π/4*G2
) P + 2πbGmP
Seating Load, Wm2 = πbGy
Where, P = Internal design pressure = 1.9024 MPa
G = Gasket reaction diameter = 485 mm
b = Effective gasket width = 5 mm
y = Gasket seating factor = 62 MPa
m = Gasket sealing factor = 3.75
Gasket factors m and y are considered from Table 2-5.1 of ASME, Section VIII, Div. 1, Ed. 2010 [9] based on
material and construction of gasket.
4. Stress calculation at tube-to-tubesheet joint using spring model and its comparison with beam model
DOI: 10.9790/1684-12462732 www.iosrjournals.org 30 | Page
Fig.6 shows structural loading and boundary conditions for model I
Fig. 6: structural loading and boundary conditions for model I
3.3 Finite Element Model (Model II)
Both tubesheet with six numbers of solid tubes i.e. one solid tube from each pass and remaining tubes as
six springs i.e. one spring for each pass are considered in model II, In order to use the spring connectors, the
applicable spring rate of the tubes is determined, so that it can maintain stiffness between tubesheet.
3.3.1 Effective spring rate:
Hooke's law for springs: F=k*d
But, axial displacement: d=F*L / (A*E)
Where, F = Axial Force due to thermal deformation, N
k = Spring Rate, N/mm
d = Displacement, mm
L = Tube Length, mm
A = Cross Sectional Area of tube hole in tubesheet, mm2
E = Modulus of Elasticity of tube material, MPa
By combining these equations: d=k*d*L/ (A*E)
Therefore, k= (A*E) /L
For area over tube holes equation becomes: k = E / L
Fig.7 shows the section view of FEA model II of tube and tubesheet with internal solid tubes and springs
Fig. 7: FE model with springs– section view of model II
3.3.2 Loading and Boundary condition:
Loadings and boundary conditions applied to model II are same as that of model I, as there is change in
only FEA model not in methodology and loading conditions. Fig. 8 and Fig. 9 shows thermal loadings and
mechanical loadings for model II respectively.
5. Stress calculation at tube-to-tubesheet joint using spring model and its comparison with beam model
DOI: 10.9790/1684-12462732 www.iosrjournals.org 31 | Page
Fig. 8: thermal loading conditions for model II Fig. 9: structural loading conditions for model II
IV. Results and discussions
On solving both models for coupled transient thermal with two structural analysis one at the end of
heating cycle (t=3Hrs) and other at the end of cooling cycle (t=7.5Hrs), maximum von mises stresses are
obtained in both models. Sections 4.1 and section 4.2 represents the details of results for model I and model II.
4.1 Finite Element Analysis Results for Model I:
Maximum axial deformation of 3.8003 mm with maximum von mises stress of 279.84 MPa is induced
in model I at the end of heating cycle, maximum stress is induced at tube-to-tubesheet junction, likely due to the
differential thermal expansion in shell and beams. Fig.10 and Fig.11 shows axial deformation and von mises
stress stress plots respectively for model I.
Fig. 10: axial deformation of shell Fig. 11: von mises stress at tube-to-tubesheet junction
Similerly, Maximum axial deformation of 3.5616 mm with maximum von mises stress of 253.79 MPa is
induced in model I at the end of cooling cycle, at tube-to-tubesheet junction. Results for model I are further
summerised in Table 3.
4.2 Finite Element Analysis Results for Model II:
Maximum axial deformation of 3.8873 mm with maximum von mises stress of 315.40 MPa is induced
in model II at the end of heating cycle, maximum stress is induced at tube-to-tubesheet junction, likely due to the
differential thermal expansion in shell and solid tube. Fig.12 and Fig.13 shows axial deformation and von mises
stress stress plots respectively for model II.
Fig. 12: axial deformation of shell Fig. 13: von mises stress at tube-to-tubesheet junction
6. Stress calculation at tube-to-tubesheet joint using spring model and its comparison with beam model
DOI: 10.9790/1684-12462732 www.iosrjournals.org 32 | Page
Similerly, Maximum axial deformation of 3.6679mm with maximum von mises stress of 268.45 MPa
is induced in model II at the end of cooling cycle, at tube-to-tubesheet junction. Results for model II are further
summerised in Table 3
V. Conclusion
Maximum von mises stresses and axial deformation for coupled transient thermal and structural
analysis of both models are shown in Table 3.
Table 3. Results summary for model I and model II
FEA Model Instance (Hrs) Model I Model II % Change
Maximum Axial
Deformation (mm)
A (3) 3.8003 3.8873 2.29
B (7.5) 3.5616 3.6679 2.98
Maximum Von mises Stress
(MPa)
A (3) 279.84 315.4 12.71
B (7.5) 253.79 268.45 5.78
Axial deformation of shell and maximum von mises stress induced at tube-to-tubesheet junction for
these two models have minimum difference under complicated mechanical and thermal loadings, so the FEA
analyses for the tubesheet with these two models are reliable.
Beam elements represent actual interaction between tubesheet and have good properties for behavior
against complicated thermal and mechanical loading, but it takes approximately 38% more computational
solving time than model with springs. Hence model with tubes as spring elements can be feasible to find out
stresses at tube-to-tubesheet junction within reasonable time frame. Comparison of different aspects of software
solver (ANSYS 15.0) for model I and model II are shown in Table 4.
Table 4. Solver output summary for model I and model II
Particular Load Case Model I Model II %Change
No. of Nodes 3395589 3161445 6.90
No. of Elements 2148464 2031066 5.46
Time required
for solution
(Hrs)
Transient Thermal 4.17 3.63 12.95
Structural Analysis 9.26 4.75 48.70
Total Time 13.43 8.38 37.60
Memory used
(GB)
Transient Thermal 10.82 10.34 4.44
Structural Analysis 25.31 23.94 5.41
The system configuration used for analysis of both model is-
Processor: Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz.
RAM: 32.0 GB. System type: 64-bit operating system, X64-based processor.
References
[1]. Ming-De X., The Basis of Tubesheet Design Rules in the Chinese Pressure Vessel Code, Pressure Vessel Piping 186:13–20, 1990.
[2]. ASME. ASME Boiler and Pressure Vessel Code, 2010 Edition, the American Society of Mechanical Engineers - New York, 2010.
[3]. TEMA, Standard of Tubular Exchanger Manufactures Association, 9th Edition, Tubular Exchanger Manufactures Association,
2007.
[4]. Wenxien Su Ning Maa, Zhifu Sang and G.E.O. Widera, Investigation of Fatigue Strength of Welded Tube to Tubesheet Joint,
Journal of Pressure Vessel Technology, vol. 131, pp 041205/1-5, August 2009.
[5]. W. Reinhardt and R. Kizhatil, Analysis of a Tubesheet Undergoing Rapid Transient Thermal Loading, Journal of Pressure Vessel
Technology, vol. 122, pp. 476-481, November 2000.
[6]. Weiya Jin and Zengliang Gao, Comparison of two FEA models for calculating stresses in shell-and-tube heat exchanger,
International Journal of Pressure Vessels and Piping 81 (2004) 563–567, 2004.
[7]. ASME. ASME Boiler and Pressure Vessel Code, Section II, Part D (metric), 2010 Edition, The American Society of Mechanical
Engineers - New York, 2010.
[8]. J.P. Holman, Heat Transfer Sixth edition, Equation 2-15, Table1 -2.
[9]. ASME. ASME Boiler and Pressure Vessel Code, Section VIII, Div. 1. 2010 Edition, the American Society of Mechanical Engineers
- New York, 2010.
[10]. Design data, geometric parameters and loading histogram are taken from Ideametrics Pvt. Ltd. Pune, India.