Browse Topic: Exhaust manifolds

Items (115)

A computational approach to Fretting Wear prediction of Steel Gaskets under Thermo-Mechanical load using Archards wear model

2024-26-027301/16/2024

IC Engine is the heart of an automobile. The failure in any component of the engine will directly affect the performance of the vehicle. The gaskets are among the many vital parts of an IC engine that are essential in ensuring appropriate sealing to prevent gas and liquid leakage and maintain optimal engine efficiency. Engines use a variety of gasket types to accommodate various sealing requirements. Among them the exhaust manifold gaskets is one of the critical gasket elements in IC engines which seals between Cylinder head and extremely hot Exhaust Manifold, this prevents the leakage of hot exhaust gasses produced during combustion. The gaskets are crucial components because they endure extremely high mechanical loads from the exhaust manifold sliding and banana-shaped bending brought on by thermal expansion, as well as extremely high thermal loads from the high exhaust gas temperatures, which are around 1000°C. These gaskets are additionally subjected to extremely high bolt loads

Reddy, Rajavardhan, Kulkarni, Sanjeev, R B, Govind, Mueller, Frank Oliver

Performance Optimization of an Exhaust System for 4 Cylinder Engine by Implementation of Computational Fluid Dynamics, Acoustic and Thermal Analysis

2022-01-076503/29/2022

The engine system requirements have changed from being focused only on delivering engine power to now having to meet environmental emission standards. The exhaust system collects exhaust gases from the combustion cylinders, eliminates dangerous pollutants, decreases noise, and discharges the purified exhaust gases at a safe distance from the vehicle's occupants. Designs of lightweight models for exhausts were always aimed at using newer lighter materials. As the design of an exhaust is more or less fixed, this approach is hardly profitable anymore. The most important components of an exhaust system are the exhaust manifold, the catalytic converter, the muffler, the resonator and connecting all of them together are connecting exhaust pipes. In this paper, the optimization of the various elements of 4 cylinder 1.8L engine exhaust system is carried out with the help of analysis software ANSYS 19.2 workbench, by performing ‘Steady State Thermal Analysis’, ‘Acoustic Analysis’ and simulating

Aiyan, Mohammed, Sagar, S Sumanth, Raghav S, Sanjay

Idle sound quality enhancement with optimizing exhaust manifold structure on a H8 engine

2022-01-073703/29/2022

Idle sound quality for motorcycle is critical to engineers to achieve. People would like to have a strong individualized sound in idle, but linear and smooth sound in driving condition. Since the idle fluctuation noise is based on the engine firing order, the exhaust manifold structure and the idle frequency by cylinder numbers, thus, compared to the two or three cylinders engines, eight or six cylinders engine are really hard to get a fluctuated tailpipe sound since the its higher firing frequency. However, the surrogate methodology can be applied on these engines. Based on the noise cancellation process in phase and amplitude in the exhaust manifold tube, engineers can manipulate the noise with several lower peaks compare to other higher peaks. In this scenario, people can feel the noise with big fluctuations although the smaller noise peaks are still there but in the masking. In this paper, a special case is presented by this methodology. In that case, an eight cylinders horizontal

Tan, Yang

Performance Optimisation of an Exhaust System for 4 Cylinder Engine by Implementation of Computational Fluid Dynamics, Acoustic and Thermal Analysis

2022-01-067703/29/2022

Aiyan, Mohammed, Raghav S, Sanjay, Sagar, S Sumanth

Thermal Calibration of Exhaust Manifold FEA Model to Enhance TMF Life Prediction

2021-28-012709/15/2021

Exhaust manifold Thermo-mechanical Fatigue (TMF) assessment using Finite Element Analysis (FEA) is complex and the results are sensitive to predicted metal temperatures on manifold. Hence it is recommended to calibrate thermal FEA model with actual test data for accurate prediction of TMF life. This helps to design reliable products. Typically, TMF life of exhaust manifold is validated using transient thermal cycle. Due to few assumptions made in simulation approach, it is observed that the difference between experimental and FEA temperature could be significant. In current approach, exhaust manifold temperature at different manifold locations are calibrated with the measured thermocouple data by varying heat transfer coefficient (HTC) at outer and inner surface of manifold. This approach is capable to provide good correlation at peak temperature and minimum temperature during the thermal cycle. However, there is no degree of freedom to calibrate transient thermal response in between

Patil, Pavan Prakash, SYRIAC, ALEX SHERJY, Kulkarni, Girish Jaiprakash

Numerical Study of the Maximum Impact on Engine Efficiency When Insulating the Engine Exhaust Manifold and Ports During Steady and Transient Conditions

2020-37-000206/23/2020

In the present work, a study about the impact on engine performance, fuel consumption and turbine inlet and outlet temperatures adding thermal insulation to the exhaust ports, manifold and pipes before the turbocharger of a 1.6L Diesel engine is presented. First, a 0D/1D model of the engine was developed and thoroughly validated by means of an extensive testing campaign. The validation was performed by means of steady state or transient running conditions and in two different room temperatures: 20ºC and -7ºC d. Once the validation was complete, in order to quantify the significance of adding thermal isolations, the simulations were performed setting the exhaust air path before the turbine as adiabatic. This is evaluated the maximum gain of the technology. Results showed that the thermal insulation proved to have a great potential in regard to T4 increase since this would reduce the warm up time of the aftertreatment systems. However, its impact on engine efficiency was limited in both

Broatch, Alberto, Olmeda, Pablo, Martin, Jaime, Dreif, Amin

Multiple 3D-DIC Systems for Measuring the Displacements and Strains of an Engine Exhaust Manifold

2020-01-054004/14/2020

In this study, a unique multi-camera three-dimensional digital image correlation (3D-DIC) system was designed and applied to an engine dynamometer cell to measure the displacement and strain of the exhaust manifold while an engine was running in a durability test. In the engine dynamometer cell, the ambient temperature varies from 25°C to 80°C~100°C cyclically and the exhaust manifold experiences high temperatures up to 900°C with high frequency vibrations. In order to obtain reliable data under such conditions, two 3D-DIC systems were designed and set up in the engine dynamometer. One is a high-speed 3D-DIC system, consisting of cameras with a sampling rate of 1250 frames per second. It was used to measure the local displacement of the bolted joint in the exhaust manifold. The high-speed measurement system is able to record the behavior of the bolt during the thermal cycles. The other system is a high-resolution 3D-DIC system, consisting of two cameras with a resolution of five-mega

Zhang, Wensheng, Li, Junrui, Yang, Lianxiang, Barber, Gary, Chen, Jim, Iqbal, Owais, Singh, Kanwerdip

Optimization of EGR Mixer to Minimize Thermal Hot Spot on Plastic Duct & Soot Deposition on Throttle Valve Using CFD Simulation

2019-26-028601/09/2019

In recent time, with inception of BS VI emission regulation with more focus on fuel economy and emission, many engine parts which were conventionally made from metal are getting replaced with plastic components for reducing weight to attain better fuel economy. EGR is commonly used technique to reduce emissions in diesel engine along with after treatment devices. EGR reduces peak combustion temperature inside the combustion chamber thereby reducing NOx. EGR is bypassed from the exhaust manifold, cooled down in EGR cooler and mixed with intake air at upstream of the intake manifold. Throttle valve is used for controlling the charged air flow to cylinders for different vehicle operating conditions. With compact engine layout EGR mixer are often located near to throttle valve thereby increasing the possibility of soot deposition on throttle valve. Once these soot & hydrocarbons cool down they can transform into sticky amorphous carbon, which obstruct the functioning of throttle valve

Agrawal, Ayush, Raju, Kumar, Santra, Tanmay, Gopinathan, Nagarajan, Varghese, Joy, Ghadei, Sataya Brata

High-Performance Rear- and Mid-Engine Vehicle Exhaust System Temperatures

2018-01-143604/03/2018

Hot surface ignition of combustible material is a known cause of vehicle fires. Although the detailed mechanisms of hot surface ignition are highly complex, the surface temperature is known to play a crucial role in this process. There has been limited previous work in the literature on this topic, much of which has focused on engine or exhaust system surface temperatures of the most common types of passenger vehicles. Also, much of this work was done in an unrepeatable manner and suffered from measurement technique induced errors. The focus of the present work is on repeatable and low measurement technique induced error temperature measurements of exhaust system surface temperatures of rear- and mid-engine sports cars. Temperature measurements were made at several points along the exhaust systems of vehicles both with and without turbo chargers on a 5-mile oval track. The exhaust system surface temperatures were examined under conditions of transient acceleration and steady-state

Papageorge, Michael, Colwell, Jeff

Thermo-Mechanical Fatigue Testing of Welded Tubes for Exhaust Applications

2018-01-009004/03/2018

Selected ferritic stainless steel sheets for exhaust applications were tested under thermo-mechanical fatigue (TMF) condition in the temperature range of 400-800 °C with partial constraint. Straight welded tubes were used as the testing coupons to withstand large compression without buckling, and to understand the effect of welding as well. Repeated tests confirmed the observed failure scenario for each material type. The hysteresis loop behaviors were also simulated using the mechanism-based integrated creep and fatigue theory (ICFT) model. Although more development work is needed, for quick material screening purpose this type of testing could be a very cost effective solution for materials and tube weld development for exhaust applications.

Quan, Guangchun, Wu, Xijia, Lafleur, Luc, zhang, Zhong

The NiceC Programming Language

TBMG-2831502/01/2018

NiceC is an improved version of ANSI C. It attempts to clean up C as much as possible using syntax translation. A type checker for NiceC is under development. The NiceC programming language is translated to, and fully compatible with, ordinary C. Thus it can be used as a drop-in replacement for C. The main benefits of using NiceC are as follows:

Experimental Investigation of Cold Start Emission using Dynamic Catalytic Converter with Pre-Catalyst and Hot Air Injector on a Multi Cylinder Spark Ignition Engine

2017-01-236710/08/2017

Control of harmful emissions during cold start of the engine has become a challenging task over the years due to the ever increasing stringent emission norms. Positioning the catalytic converter closer to the exhaust manifold is an efficient way of achieving rapid light-off temperature. On the other hand, the resulting higher thermal loading under high-load engine operation may substantially cause thermal degradation and accelerate catalyst ageing. The objective of the present work is to reduce the light-off time of the catalyst and at the same time reduce the thermal degradation and ageing of the catalyst to the minimum possible extent by adopting an approach with Dynamic Catalytic Converter System (DCCS). The emission tests were conducted at the cold start of a 4 cylinder spark ignition engine with DCCS at different positions of the catalyst at no load conditions. Also emission tests were conducted with pre-catalysts of 20% volume and 40% volume of the main catalytic converter and

Mahadevan, Ganesan, Subramanian, Sendilvelan

Scavenge Ports Ooptimization of a 2-Stroke Opposed Piston Diesel Engine

2017-24-016709/04/2017

This work reports a CFD study on a 2-stroke (2-S) opposed piston high speed direct injection (HSDI) Diesel engine. The engine main features (bore, stroke, port timings, et cetera) are defined in a previous stage of the project, while the current analysis is focused on the assembly made up of scavenge ports, manifold and cylinder. The first step of the study consists in the construction of a parametric mesh on a simplified geometry. Two geometric parameters and three different operating conditions are considered. A CFD-3D simulation by using a customized version of the KIVA-4 code is performed on a set of 243 different cases, sweeping all the most interesting combinations of geometric parameters and operating conditions. The post-processing of this huge amount of data allow us to define the most effective geometric configuration, named baseline. In the second step of the study, the baseline is further optimized, keeping into account some fundamental design constraints, such as the

Mattarelli, Enrico, Rinaldini, Carlo, Savioli, Tommaso, Cantore, Giuseppe, Warey, Alok, Potter, Michael, Gopalakrishnan, Venkatesh, Balestrino, Sandro

Efficiency Improvement by Separation of Vapor and Liquid in Condenser Headers

2017-01-018003/28/2017

This paper introduces the concept of separation of two-phase flow in condenser as a way to improve condenser efficiency. The benefits of vapor-liquid refrigerant separation and the reason why it will improve the condenser performance are explained. Numerical studies are presented on the effects of separation on performance of an R134a microchannel condenser, with the comparison to experiment data. Model predicts that at the same mass flow rate, the exit temperature is lower by 2.2 K in the separation condenser compared with that in the baseline. Up to 9% more flow rate of condensate is also predicted by the model in the separation condenser. Experiment results confirm the same trend. In addition, the reason why a certain circuiting of passes with pre-assumed separation results in the header improves the condenser is investigated by the model and results are presented.

Li, Jun, Hrnjak, Pega

Thermomechanical Analysis of Diesel Engine Exhaust Manifold

2016-36-025810/25/2016

This study focuses on the Termomechanical Fatigue (TMF) analysis for an exhaust manifold. Bolt tension and temperature field has been applied in order to get variation on stresses, going from room load condition to a full load condition. The temperature field has been acquired from 1D simulation and adjusted to fit experimental values measured on the vehicle. Low cycle fatigue (LCF) has been considered to evaluate the exhaust manifold under the stress cycles produced by temperature fluctuation. Thermal and stress analysis have been performed by Abaqus package. An in-house code has been employed in the fatigue analysis. The bolt torque and the temperature field on the engine and exhaust manifold are the loads considered in the analysis.

de Azevedo Cardoso, Ademar, Andreatta, Ederson Claudio

Thermo-Mechanical Fatigue Study of Gasoline Engine Exhaust Manifold Based on Weak Coupling of CFD and FE

2016-01-235010/17/2016

This paper combines fluid software STAR-CCM+ and finite element software ABAQUS to solve the temperature field of this Gasoline engine exhaust manifold based on loose coupling method. Through the simulation of car parking cooling - full load condition at full speed, we estimate thermal fatigue life of the exhaust manifold with the plastic strain increment as the evaluation parameters. It can guide the direction of optimal design of the exhaust manifold. Here we also revealed how the bolt force affects the manifold elastic and plastic behavior.

Liu, Zhien, Chen, Jiangmi, Xiao, Sheng-hao

The Analysis of Phase Separation in Vertical Headers of Microchannel HEs

2016-01-025304/05/2016

This paper presents the experimental analysis of separation in vertical headers based on flow visualization. Two-phase separation phenomena inside the header is observed and quantified. Driving forces are analyzed to study the mechanisms for two-phase flow motion and flow regimes. Main tube of the header is made of clear PVC for visualization study. R-134a is used as the fluid of interest and the mass flux from the inlet pass is 55 kg/m2s - 195 kg/m2s. Potential ways to improve two-phase separation are discussed. A model is built to show how separation brings potential benefits to MAC heat exchangers by arranging the flow path.

Li, Jun, Hrnjak, Predrag

Thermal Analysis of Heavy Duty Engine Exhaust Manifold Using CFD

2016-01-064804/05/2016

The exhaust manifold bridges the gap between the engine structure and the hot-end after-treatment system, the burned in-cylinder gases are disposed through the manifold. The automotive exhaust manifolds are designed and developed for providing a smooth flow with low/least back pressure and must be able to withstand extreme heating under very high temperatures and cooling under low temperatures. The paper presents a theoretical study aiming to investigate the feasibility of three different CAE approaches and techniques used for the simulation of exhaust manifold fluid flow and the accompanying thermal distribution. The main difficulty emanates from the pulsating nature of fluid flow inside the engine exhaust manifold. To verify the outcome of each solution experimental measurements of the manifold temperatures have been performed. The predicted metal temperature is then used to carry out the thermo-structure durability analysis to evaluate the design of HD diesel engine exhaust manifold

Eroglu, Sinan, Duman, Ipek, Ergenc, Alp, Yanarocak, Rıfat

Exhaust Manifold Durability Subject to Splash Quenching

2015-01-173504/14/2015

Exhaust manifold design is one of the more challenging tasks for the engine engineer due to the harsh thermal and severe vibration environment. Extremely high exhaust gas temperatures and dynamic loading combine to subject the manifold to high cyclic stress when the material has reduced fatigue strength due to the high temperature. A long service life before a fatigue failure is the objective in exhaust manifold design. Accumulation of fatigue damage can occur from dynamic loading and thermal loading combined. Thermal mechanical fatigue (TMF) is a primary mechanism for accumulating fatigue damage. TMF typically occurs when a vehicle driving cycle has operating conditions that repeatedly change the exhaust gas temperature between hot and cold. Another way to experience temperature cycling is through splash quenching. Splash quenching was analyzed and found to rapidly accumulate fatigue damage. An experimental and analytical method is presented that quantified splash quenching and the

Wade, Robert, Hsieh, Jerry C.

Phase Separation in Second Header of MAC Condenser

2015-01-169404/14/2015

This paper presents results of the visualization of the separation in the vertical header of the automotive condenser. A prototype of a heat exchanger was made that has inlet in the middle of the header, with 21 microchannel tubes as the first pass. In the second header liquid separates and leaves through 4 microchannel tubes beneath while mostly vapor leaves through 11 microchannel tubes on the top as another exit. That way the 2nd pass has liquid below first pass and vapor above it. R134a was used in the tests. Mass flow at the inlet to the header was in the range 8.4 - 30 g/s (mass flux of 54 kg/m2·s-193 kg/m2·s) and quality at the inlet to second header was varied over a range of 0.05 to 0.25, to see their impact on the separation of two-phase flow inside the transparent header. Visualization was performed to better understand and define the physical parameters that dominate the separation phenomena. Efficiencies of separation are defined to quantify the separation effect of the

Li, Jun, Hrnjak, Predrag

Design of the Exhaust Manifold of a Turbo Charged Gasoline Engine Based on a Transient Thermal Mechanical Analysis Approach

2014-01-288210/13/2014

The present paper describes a CAE analysis approach to evaluate the design of exhaust manifold of a turbo charged gasoline engine. It allows design engineers to identify structural weakness at the early stage or to find the root cause of exhaust manifold failures. A transient none-linear finite element method is used to calculate the plastic deformation and thermal mechanical behaviors of the exhaust manifold assembly during thermal shock cycles, which include rated speed full load, rated speed motored and idle speed conditions. A transient heat transfer simulation is performed to provide thermal boundary conditions for the nonlinear stress/strain analysis. The finite element model includes a part of cylinder head, exhaust manifold, gaskets, turbo charger housing, catalytic converter, brackets, bolts and nuts. The results show that plastic deformation is the main cause of manifold cracking and the manifold flange distortion causes the exhaust leakage. The simulation results indicate

Chen, Ming, Wang, Yanjun, Wu, Wenrui, Xin, Jun

Muffler Sound Development Using Analysis of Acoustic Source of Engine Exhaust System

2014-01-002604/01/2014

In order to achieve the proper automobile interior sound, the tailpipe noise of the exhaust system must be considered as a main contributor. This paper describes a study of the achievement of dynamic sound quality through exhaust system design. Firstly, we determined the vehicle's interior sound quality and established a target sound using a subjective assessment of 10 benchmark vehicles. The exhaust noise target is determined by means of transfer path analysis focusing on the noise source and how it's impacted by the muffler design. The exhaust system is commonly modeled as a combination of source strength and impedance. We obtained the source character by the wave decomposition method using two microphones and six loads ultimately leading to an optimized design of the inner muffler structure. Based on this study, we achieved dynamic interior sound and improved exhaust system performance.

Han, HakSon, Park, ChulMin, Heo, JeongHoi, Kang, Sang Kyu

Study on the Unsteady Heat Transfer of Engine Exhaust Manifold Based on the Analysis Method of Serial

2014-01-171104/01/2014

In order to predict the thermal fatigue life of the internal combustion engine exhaust manifold effectively, it was necessary to accurately obtain the unsteady heat transfer process between hot streams and exhaust manifold all the time. This paper began with the establishment of unsteady coupled heat transfer model by using serial coupling method of CFD and FEA numerical simulations, then the bidirectional thermal coupling analysis between fluid and structure was realized, as a result, the difficulty that the transient thermal boundary conditions were applied to the solid boundary was solved. What's more, the specific coupling mode, the physical quantities delivery method on the coupling interface and the surface mesh match were studied. On this basis, the differences between strong coupling method and portioned treatment for solving steady thermal stress numerical analysis were compared, and a more convenient and rapid method for solving static thermal stress was found. Finally

Zhien, Liu, Wang, Xiaomin, Yan, Zhang, Li, Xueni, Xu, Yu

Modularity Adoption in Product Development: A Case Study in the Brazilian Agricultural Machinery Industry

2013-01-909301/15/2014

Facing a competitive and globalized market and with increasingly demanding customers, companies must constantly seek the development of practices in the development of new products. One of the current practices is the adoption of modularity. In that sense, the objective of this paper is to conduct an analysis of this practice in a Brazilian company, which manufactures agricultural machinery. The applicability of modular design in current products is focused. Therefore, a case study approach has been chosen. First, a review of the scientific literature was conducted, followed by field research, for collecting data based on interviews with product engineers and technical documentation. The case study shows the applicability of the modular design concept in a combine header, by increasing the number of repeated components. The modular header approach facilitates the implementation of engineering changes and allows greater standardization of components. In addition, it contributes for

Mayer de Ávila, Rodrigo, Borsato, Milton

Evaluation of Dynamic Characteristics of an Automotive Exhaust System using Operational Modal Analysis (OMA) and Experimental Modal Analysis (EMA)

2013-01-290311/27/2013

NVH refinement has gained increased importance in the automotive industry especially in the last two decades, due to increased global competition and customer requirements. Furthermore, owing to the stringent legislative requirements on the radiated noise levels have also put additional demands on the automotive industry from the NVH perspective. Engineers have been constantly focusing on improving NVH evaluation techniques and test methodologies to improve the quality of test data, ease of measurement and productivity. The traditional input/output technique based modal analysis has always been an NVH engineer's favorite tool, for identifying the dynamic behavior of the component / BIW / vehicle in whole. The knowledge of a structure's modes and mode shape gives sufficient information of the component with respect to the system's modal alignment, for further optimization of performance, weight and for updating the CAE model. The alternative technique for dynamic characteristics

Iyer, Ganesh, Mohan, Sakthivel, Rao, Naveen, Unnithan, Sarat

The Analysis of Crack Mechanism and Estimate of Life Time by the Vibration Measurement of Stainless Exhaust Manifold in Firing Condition

2013-01-264310/14/2013

SUS exhaust manifold is weaker than cast iron in aspect of high temperature vibration. So as to improve reliability of SUS exhaust manifold and get over gas temperature limit, exhaust manifold vibration mode and level has to be decreased. And because of error and limit of conventional modal analysis, we measured vibration mode and level of SUS exhaust manifold directly in engine firing condition. To measure vibration of hot parts(600∼800°C) in engine, we used special cooling device at base of accelerometer. Thus we developed analysis method of SUS exhaust manifold crack mechanism. We came to know the accurate vibration mode and level of SUS exhaust manifold in hot condition. Besides, we found out in proportion as vibration level increases endurance life decreases.

Kim, Han Sang, Park, Sang Joon

Logistics Product Data Reports Handbook

TAHB0007_1 (Historical)05/01/2013

This document describes a set of standardized reports that can be generated using the logistics product data elements contained in GEIA-STD-0007-B. Each report is defined by selection options, processing, format, report sequence, and data sources. The selection options paragraph identifies recommended mandatory and optional selections that can be made by the user to tailor the report content. The processing paragraph identifies qualifying criteria for report data, report calculations, and specific instructions regarding how the data should be presented on the report. Each report has a sample report showing its format. Report sequences specify the sort criteria for a given report, and each Part/Section within a report. There is an attached listing of data sources for the elements that are on a report. The listing provides the report header for each element; and its GEIA-STD-0007-B data element/attribute along with the appropriate entity. The data source listings were developed by

LCLS Life Cycle Logistics Supportability

Fe-Si Sintered Alloy for use in Exhaust Applications

2013-01-115404/08/2013

As a result of the wide range of operating environments, component parts of automotive and commercial engine exhaust systems require a unique combination of material properties that are not easily met using existing wrought, cast, or powder metallurgy alloys. Alpha Sintered Metals (ASM) now offers a new Powder Metal (PM) alloy with improved hot oxidation properties that not only supplements the application of traditional stainless steel alloys but also enhances the service life reliability of these components for elevated exhaust temperature applications. ASM's new alloy named Alphaloy, demonstrates material property advantages for several critical exhaust system attributes. The test results of studies comparing Alphaloy to other traditional materials exhibit improved performance relative to hot oxidation resistance, tensile strength and machinability while maintaining consistent performance for thermal expansion, atmospheric corrosion and weldability. Alphaloy's excellent resistance

Cornelio, Thomas, Schloder, Michael R., O'Neill, Michael, Bowyer, Stephen, Vrsek, Gary

The Fluid Induced Vibration Analysis on an Integrated Exhaust Manifold

2013-01-093704/08/2013

With its advantages on cost and performance, the integrated exhaust manifold (casting with the turbine) is being used on more vehicles by auto makers. Generally, when compared with the divided exhaust manifold, the integrated exhaust manifold stands for higher vibratory excitation from gas dynamics. In this paper, the gas dynamics excitation has been computed through the GD (gas dynamics) software GT-Power which calculates the exhaust pipe surface pressure, and CFD code Star-CCM+ which calculates the turbine blade force. And the response of manifold has been solved under this excitation. On the other hand, the mechanical excitation has been computed through the MBD (multi-body dynamics) platform AVL-Excite-PU, and the responses under the gas excitation plus the mechanical load have been studied in order to analyze the effects of the fluid excitation on an integrated manifold. The results show that the pressure fluctuation has more energy input than blade force, but both of them are

Deng, BangLin, Liu, Jingping, Feng, Renhua, Zhang, Daming

Experimentally Validated Model of Refrigerant Distribution in a Parallel Microchannel Evaporator

2012-01-032104/16/2012

This paper develops a model for a parallel microchannel evaporator that incorporates quality variation at the tube inlets and variable mass flow rates among tubes. The flow distribution is based on the equal pressure drop along each flow path containing headers and tubes. The prediction of pressure drop, cooling capacity, and exit superheat strongly agree with 48 different experimental results obtained in four configurations using R134a. Predicted temperature profiles are very close to infrared images of actual evaporator surface. When compared to the uniform distribution model (that assumes uniform distribution of refrigerant mass flow rate and quality) results from the new model indicate superior prediction of cooling capacity, and exit superheat. Model results indicate maldistribution of refrigerant mass flow rate among the parallel tubes, caused primarily by pressure drop in the outlet header.

Tuo, Hanfei, Bielskus, Algirdas, Hrnjak, Pega

Development of Unified Exhaust System Supported by CAE Software Programs

2010-36-047310/06/2010

In spite of the changes in vehicle performance, one of the current challenges is to get components applicable to different vehicles with no changes in the project. Simulations made with specific numerical programs enable this process of unifying components, for different platforms, to be applied to the exhaust system. The projects proposed, based on the results obtained with the simulation programs, were tested experimentally. It was proven that the results of the simulation proposals correlated to the experimental results. This ultimately provided simplification to the project, with gains in logistics and productivity. Besides the technological process involved, possibilities to reduce costs can also be considered.

de Oliveira, Anderson Ricardo, da Silva Moura, Marcio, da Silva de Amorim, Osmar, de Oliveira Silva, Ricardo

Exhaust Manifold Structural Analysis Focusing Mass Reduction for Vehicular Diesel Engine Application

2010-01-050204/12/2010

This Paper presents a study of weight reduction in an exhaust manifold of a four cylinders, 3.0 liters Diesel engine. The mass of the entire engine shall be reduced from the current 290kg to 260kg and many components will be redesigned focused on this target. Basically, the wall thickness and flanges of the exhaust manifold will be redesigned and reduced to a value which shall guaranties the component durability. The calculations will be made determining the life cycle of the proposed exhaust manifold, checking if no structural problems can occur. The shape and size of the ducts remain unchanged for performance purposes and no material changes will be considered for the new component.

Mendes, Alexandre Schalch, Tomoyose, Rodrigo

Steady-State and Transient Motor Vehicle Exhaust System Temperatures

2009-01-001304/20/2009

One of the known causes of motor vehicle fires is hot surface ignition of combustible material that contacts engine exhaust system components. While ignition is a complicated phenomenon, the temperature of the surface is known to be an important parameter. However, little data is available in the literature concerning exhaust system temperatures, and much of this data is confounded by thermocouple attachment techniques and undocumented variations in driving conditions. In the present study, engine exhaust system temperature measurements were conducted using six test vehicles on a level, 2-mile oval test track at constant vehicle speeds ranging from 0 (idle) to 70 mph. By normalizing transient temperature curves with these steady-state temperatures along with ambient temperature, the rates at which the exhaust system components warm up and cool down are also compared. The effect of thermocouple mounting technique was evaluated by conducting identical testing with the thermocouples

Colwell, Jeff D., Biswas, Kaushik

Simulation on Thermal-Stress-Fatigue of an Engine Exhaust Manifold

2009-01-040904/20/2009

Because of the contradictions of the downsizing and the serious thermal-load of modern engine, thermal fatigue failure of the engine components easily happens due to excessive temperature gradient and thermal stress. During recent years, with the constantly advancing progress of high performance computer technology, many CFD software codes provide the ability to solve, or take part in the best possible solution of FVM/FEM coupled problems, and Fluid Structure Interaction (FSI) analyses have been developed. However, the unidirectional coupling of thermal flow and thermal stress as well as structural fatigue failure analyses in IC engine applications, especially transient case, has received less attention. In this paper, authors have studied unidirectional FSI in depth, including that transient high speed and high temperature flow strongly affects the engine exhaust manifold. These researches can be used in protection certain fatigue failures for general purpose. And CFD and FEA code

Dong, Fei, Fan, Qinyin, Guo, Chenhai, Jiang, Shuli, Cai, Yixi, Miyori, Akio, Washio, Saji

An Integral Engineering Solution for Design of Exhaust Manifolds

2009-01-122904/20/2009

Thermomechanical fatigue (TMF) cracks on exhaust manifolds are often observed for highly loaded engines due to increasing performance and emission demands from the market. Continuously, higher strength materials are searched for, where maximum gas temperatures in some cases are already in excess of 1000 °C. In order to save cost and time, development strategy is built on performing tests on a virtual prototype instead of a physical prototype. The use of advanced simulation technologies enables the design and analyses engineers to identify critical locations in an early phase of development and to meet measures in order to remove local structural weaknesses. During the last decades, several methods are published for the identification phase; considering kinematic and isotropic hardening, creep in material modeling and considering plasticity, creep and oxidation in lifetime modeling. In this paper, in addition to a reliable approach for failure prediction we focus on the removal of

Gocmez, Taner, Deuster, Udo

RapidIO vs. Ethernet A Practical Technical Comparison

TBMG-619609/01/2008

Ethernet is currently the incumbent backplane technology across a wide range of storage, wireless, wireline, military, industrial, and other embedded applications as developers move away from proprietary implementations in an effort to reduce development time and cost while increasing performance and functionality. However, as data rates increase, it has become apparent that many high-performance applications exceed the limits of this traditional protocol. Designing an efficient embedded backplane interconnect with excellent performance requires addressing a number of key design challenges, including header efficiency, protocol processing efficiency, effective bandwidth, and quality of service while strictly managing cost. To meet these challenges, many developers are turning to RapidIO® technology as an alternative to Ethernet.

A Mean-Value Model for Estimating Exhaust Manifold Pressure in Production Engine Applications

2008-01-100404/14/2008

A key quantity for use in engine control is the exhaust manifold pressure. For production applications it is an important component in the calculation of the engine volumetric efficiency, as well as EGR flow and residual fraction. For cost reasons, however, it is preferable to not have to measure the exhaust manifold pressure for production applications. For that reason, it is advantageous to develop a model for estimating the exhaust manifold pressure in production application software that is small, accurate, and simple to calibrate. In this paper, a mean-value model for calculating the exhaust manifold pressure is derived from the compressible flow equation, treating the exhaust system as a fixed-geometry restriction between the exhaust manifold and the outlet of the tailpipe. Validation data from production applications is presented.

Olin, Peter M.

Fitting Assembly, Straight, Female Flareless, Axially Swaged, Hydraulic, 5080 psi

AS5974A (Historical)01/04/2008

Scope unavailable.

G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies

Fitting Assembly, Union, Axially Swaged, Hydraulic, 5080 psi

AS5969A (Historical)07/26/2007

Scope unavailable.

G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies

Fitting Assembly, Tee, Axially Swaged, Hydraulic, 5080 psi

AS5972B (Historical)07/26/2007

Scope unavailable.

G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies

Estimating Actual Exhaust Gas Temperature from Raw Thermocouple Measurements Acquired During Transient and Steady State Engine Dynamometer Tests

2007-01-033504/16/2007

Thermocouples are commonly used to measure exhaust gas temperature during automotive engineering experiments. In most cases, the raw measurements are used directly as an absolute indication of the actual exhaust gas temperature. However, in reality, the signal from a TC is only an indication of its own tip temperature. The TC indicated tip temperature can deviate significantly from the actual gas temperature due to factors such as thermal capacitance of the tip itself, and heat transfer to the exhaust pipe wall through conduction and radiation. A model has been developed that calculates the effects of these factors to provide an estimate of the actual exhaust gas temperature. Experiments were performed to validate the model under both transient and steady state engine dynamometer conditions utilizing three popular sizes of TCs. Good correlation among predictions for various TC sizes confirms the model's accuracy. This tool enhances the quality of exhaust gas temperature measurements

Son, Seha, Kolasa, Arthur E.

Thermal Fatigue Design of Stainless Steel Exhaust Manifolds

2007-01-056404/16/2007

The paper deals with the thermal mechanical fatigue (TMF) of stainless steels used for exhaust manifolds. A thermal fatigue test on V-shape specimen was early developed at Ugine & Alz to simulate such thermal and mechanical conditions. The examination of failed specimens indicates that cracks could be generally attributed to out-of-phase TMF. However, in specific cases, in-phase TMF may be dominant. For instance, manifolds made of austenitic stainless steel grades usually fail by in-phase TMF. Based on finite element calculation of the V-shape test, a damage criterion is proposed for out-of-phase TMF, which correlates the amplitude of the viscoplastic strain, the maximal temperature, the dwell time during the thermal cycle and the number of cycles to failure.

Chinouilh, G., Santacreu, P. O., Herbelin, J. M.

The optimization of Exhaust and Catalytic Converter System for ULEV-II using the Robust Design

2007-01-056004/16/2007

The conventional aftertreatment systems to meet the stringent ULEV-II emission regulation are usually composed of warm-up catalytic converter (WCC) and underfloor catalytic converter (UCC). However, those systems bring high cost, high back pressure, the limit of engine room for package design, and other side effects.[4] The new optimized system needs to solve these problems and to meet ULEV-II emission regulation efficiently. There are many technologies and design parameters in exhaust catalytic converter systems; exhaust manifold structure[9], exhaust gas flow distribution, location of catalytic converter, PM coating technologies[1], substrate characteristics, and volume of catalysts. It is a key factor to make a optimized robust system with those parameters and technologies described. The new optimized exhaust and Integrated Close-coupled Catalytic Converter (ICCC) system can meet ULEV-II regulation and can solve those problems of conventional system by a robust design. This study

Kim, Sangbeom, Kim, Sungkun, Park, Yongjung, Kim, Youngbum, Kim, Hyunsoo, Lee, Seungseok, Yeon, Taehun

Exhaust System Sounds

2006-01-137204/03/2006

More and more automobile manufacturers are requiring a typical sound pattern for a car or a platform, even the unique „brand sound” for a whole brand, on the top of their specification. By this image factor sound design becomes increasingly important for the exhaust system development. The whole sound pattern, especially the tailpipe noise of the exhaust system, plays an important role at the subjective impression of the car [1, 2]. There are two sound classifications: the limousines with an harmonic, quiet and discrete sound whereas for sports cars a more rough and powerful sound is requested. Compared with the gasoline engine the diesel engine has, based on inner power driven processes, a minor sound spectrum because its harmonics and main orders are hardly audible and mostly attenuated by a turbo charger. For turbo charged engines special concepts have been worked out in order to achieve a sporty sound. Especially resonances of the connecting pipes and the muffler chambers are used

Fuhrmann, Bernd, Garcia, Patrick, Wiemeler, Dirk

Passive Exhaust System With Cylinder Deactivation

2005-01-235105/16/2005

Cylinder deactivation is an efficient way to significantly improve fuel economy without compromising the horsepower and torque. For an exhaust system to manage both V4 and V8 modes, a unique development approach for exhaust system design needs to be incorporated. Simulation tools and correlation testing can be used to achieve great sound quality without the use of an active valve design classically (believed to be required) implemented. A quasi-Computer Aided Engineering (CAE) 1-Dimensional code drove the design of the passive (without a valve) system. The 1-Dimensional code analyzes pressure waves, mass flow and energy losses in ducts and junctions. To achieve the objective for cylinder deactivation, this tool also allows significant changes with relatively fast results for trends to be evaluated. The goal for this cylinder deactivation system was to have a smooth transition between the two modes and achieve the commercial performance with low backpressure. The challenge of this

Bemman, Ya-Juan, Frei, Tom, Jones, Chris, Keck, Mathias

Simulation of Radiation Effects in the Presence of the Exhaust System

2005-01-206005/10/2005

The increasing packing and power density in vehicles makes the thermal environment in the engine compartment more and more severe. A critical area in terms of radiation are the components facing the exhaust system. This paper shows the simulation methods applied at MAGNA STEYR finding hot spots and endangered parts when looking on the effects of radiation. The simulation runs in parallel to design, gives a reliable rating of variants and helps the designer to optimize his system. The influence of an exhaust manifold design change from double-walled to a single-walled on the steering system in a right hand drive vehicle is shown. This change was done due to cost reduction, but also resulted in additional costs for heat protection. The methods are applied in advance of the physical prototypes and help to find good measurement positions for the physical testing also.

Moshammer, Thomas

Class B Data Communication Network Messages--Part 3--Frame IDs for Single-Byte Forms of Headers

J2178/3_200407 (Historical)07/27/2004

This SAE Recommended Practice defines the information contained in the header and data fields of non-diagnostic messages for automotive serial communications based on SAE J1850 Class B networks. This document describes and specifies the header fields, data fields, field sizes, scaling, representations, and data positions used within messages. The general structure of a SAE J1850 message frame without in-frame response is shown in Figure 1. The structure of a SAE J1850 message with in-frame response is shown in Figure 2. Figures 1 and 2 also show the scope of frame fields defined by this document for non-diagnostic messages. Refer to SAE J1979 for specifications of emissions related diagnostic message header and data fields. Refer to SAE J2190 for the definition of other diagnostic data fields. The description of the network interface hardware, basic protocol definition, electrical specifications, and the CRC byte is given in SAE J1850. SAE J1850 defines two and only two formats of

Vehicle Architecture For Data Communications Standards

Class B Data Communication Network Messages - Part 2: Data Parameter Definitions

J2178/2_200407 (Historical)07/27/2004

This SAE Recommended Practice defines the information contained in the header and data fields of non-diagnostic messages for automotive serial communications based on SAE J1850 Class B networks. This document describes and specifies the header fields, data fields, field sizes, scaling, representations, and data positions used within messages. The general structure of a SAE J1850 message frame without in-frame response is shown in Figure 1. The structure of a SAE J1850 message with in-frame response is shown in Figure 2. Figures 1 and 2 also show the scope of frame fields defined by this document for non-diagnostic messages. Refer to SAE J1979 for specifications of emissions related diagnostic message header and data fields. Refer to SAE J2190 for the definition of other diagnostic data fields. The description of the network interface hardware, basic protocol definition, electrical specifications, and the CRC byte are given in SAE J1850. SAE J1850 defines two and only two formats of

Vehicle Architecture For Data Communications Standards

Class B Data Communication Network Messages - Detailed Header Formats and Physical Address Assignments

J2178/1_200407 (Historical)07/27/2004

This SAE Recommended Practice defines the information contained in the header and data fields of non-diagnostic messages for automotive serial communications based on SAE J1850 Class B networks. This document describes and specifies the header fields, data fields, field sizes, scaling, representations, and data positions used within messages. The general structure of a SAE J1850 message frame without in-frame response is shown in Figure 1. The structure of a SAE J1850 message with in-frame response is shown in Figure 2. Figures 1 and 2 also show the scope of frame fields defined by this document for non-diagnostic messages. Refer to SAE J1979 for specifications of emissions related diagnostic message header and data fields. Refer to SAE J2190 for the definition of other diagnostic data fields. The description of the network interface hardware, basic protocol definition, the electrical specifications, and the CRC byte are given in SAE J1850. SAE J1850 defines two and only two formats of

Vehicle Architecture For Data Communications Standards

Class B Data Communication Network Messages--Message Definitions for Three Byte Headers

J2178/4_200407 (Historical)07/27/2004

This SAE Recommended Practice defines the information contained in the header and data fields of non-diagnostic messages for automotive serial communications based on SAE J1850 Class B networks. This document describes and specifies the header fields, data fields, field sizes, scaling, representations, and data positions used within messages. The general structure of a SAE J1850 message frame without in-frame response is shown in Figure 1. The structure of a SAE J1850 message with in-frame response is shown in Figure 2. Figures 1 and 2 also show the scope of frame fields defined by this document for non-diagnostic messages. Refer to SAE J1979 for specifications of emissions related diagnostic message header and data fields. Refer to SAE J2190 for the definition of other diagnostic data fields. The description of the network interface hardware, basic protocol definition, the electrical specifications, and the CRC byte are given in SAE J1850. SAE J1850 defines two and only two formats of

Vehicle Architecture For Data Communications Standards

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