Thermal load analysis and optimization of high power density diesel engine cylinder head

To evaluate the thermal load level and security of a newly designed cylinder head, with a V8, high power density diesel engine as the research object, the fluid-structure coupling simulation of the cylinder head and water jacket on one single side was calculated and the thermal-mechanical coupling stress analysis of the same cylinder head was performed considering the imbalance of each cylinder explosion. It was found that the highest temperature and the maximum thermal stress on these four flame decks respectively appears on the exhaust bridge zone and the intake bridge zone of the 3rd flame deck. Based on the analysis on the results, water jacket improvements were made. According to the position and the number of the holes, a set of optimization ideas were put forward, eventually the optimized scheme of obvious effects was got and compared with the original scheme. Results show that on the flame deck of the optimized scheme the highest temperature reduced 6.2 K, the maximum equivalent stress reduced 21.4 MPa, which can provide certain references for design optimization of diesel engine cylinder head. ©, 2015, Zhejiang University. All right reserved.