March 6 - 8, 2017 | Berlin
LEADING ENGINEERING SIMULATION CONFERENCE
Thermal assessment of HD engine exhaust manifold with co-simulation method and optimization study for external heat transfer coefficient
In the automotive engineering, exhaust manifold which is mounted on cylinder head of an engine, collects the exhaust gas from the cylinders and dispose it to the exhaust after treatment system. Nowadays, increase of engine performance and overall system efficiency are the most struggling questions seen in the automotive industry. On the other hand; safety, fuel economy and price are the demands from the customer. To satisfy all these market expectations regarding to the emission and performance of engine, the temperature of the exhaust gas disposed from the engine becomes too high. During the engine operation, exhaust manifold is subjected to severe thermal cycling under harsh working conditions, resulting from high temperature exhaust gases, which also show transient behavior.
Exhaust manifold also requires the long running design verifications tests to be conducted in dynamometer test center which are very expensive and time consuming (up to 2500 hours). CAE is best method to minimize the costly hardware testing and reduce whole product development time. The current study presents the well-developed CAE process to predict the exhaust manifold metal temperature accurately which is used to carry out thermo-mechanical analyses to evaluate the design of the heavy-duty diesel engine exhaust manifold in terms of durability. As a first part of this study, performed the STAR-CCM+® Co-Simulation analyses via 1D engine performance data as boundary condition. It was managed to determine the non-uniform heat transfer distribution for external surface of manifold (without performing external aerodynamics analysis) via using DOE based optimization strategy. Also obtained metal skin temperature of manifold with thermal camera and thermocouple within the scope of this study to validate the CFD result with the experimental data.