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The exhaust system design and development need to be more flexible and easily adaptable for the requirement of dynamic changes to meet the upcoming emission and noise regulations. Durability of exhaust system components are evaluated through conventional bending moment testing using specified standard load conditions. Road load re-production test is an improvement of the conventional approach to predict component weld durability. It involves the systematic and sequential process of acquiring road load data such as sensor instrumentation, strain measurement at the test track, data processing and input to Bi-Ax testing. S/N Curve testing is introduced recently as an alternate method to minimize the use of road load reproduction testing. It involves prediction of rough force using transient response analysis followed by Bi-Ax testing for the derived high and low load forces to meet the target number of cycles to failure.

While advanced automotive system assemblies contribute greater value to automobile safety, reliability, emission/noise performance and comfort, they are also generating higher temperatures that can reduce the functionality and reliability of the system over time. Thermal management and proper insulation are extremely important and highly demanding for the functioning of BSVI and RDE vehicles. Frugal engineering is mandatory to develop heat shield in the exhaust system with minimum heat loss. Heat shield design parameters such as insulation material type, insulation material composition, insulation thickness, insulation density, air gap thickness and outer layer material are studied for their influences on skin temperature using mathematical calculation, CFD simulation and measurement. Simulation results are comparable to that of the test results within 10% deviation.

Tube bends are critical in an exhaust system. The acceptability of tube bends is based on the induced level of shape imperfections considered. An analysis is presented for the performance tuning of the genetic algorithm including the importance of raw material selection, ovality and elongation property. This study is an attempt to analyze the ovality effect of STAC 60/60 material. CAE tools are essential to exploit the design of experiments and find out the optimum values of the design parameters in comparison with full factorial designs. Especially the effects of materials, dimensions and geometry shape of the ultimate strength were discussed by both CAE and experiments. The ultimate strength of steel tube was evaluated at least 20-30% as a local strain independent of the materials. The dependency of ultimate bending angle on original centre angle of the tube bend was clarified.

The numerical methodology is developed to estimate the backpressure value acquired from the cold flow bench into the hot flow conditions by equalizing various gas flow properties such as gas density and gas constant. The exhaust muffler geometry is adopted for virtual analysis. Computational Fluid Dynamics (CFD) modeling of the exhaust muffler in hot and cold flow conditions shows 60% of difference in back pressure values. The same muffler sample is tested in hot and cold flow test bench for back pressure on same measurement location used in CFD tool, the test result difference between these two conditions is obtained as 61%. By using derived 1D calculation, the cold flow back pressure results are extrapolated to generate hot flow back pressure values for the exhaust muffler system. These extrapolated values are then validated with the back pressure analysis results performed in both CFD and flow test bench using cold and hot flow conditions.

Generation of discretization with prescribed element sizes are adapted to the geometry. From the rules of thumb, for a complicated geometry it is important to select the reasonable element order, shapes and size for accurate results. In order to that, this paper describes the influence of elemental algorithm of the catalytic converter mounting brackets. Brackets are main source of mounting of various systems mainly intake and exhaust in the engine. In hot end exhaust system, a bracket design plays a vital role because it has to withstand heavy structural vibrations without isolation combined with thermal loads. Bracket design and stiffness determines the whole catalytic converter system's rigidity. So, here discretization of converter brackets by linear and parabolic elements is studied with different elements types and compared.