高速船用汽油机缸盖水套CFD分析及优化

CFD Analysis and Optimization of Method of a High-speed Marine Gasoline Engine Cylinder Head and Water-jacket

以某高速船用汽油机气缸盖为研究对象,利用商业软件CFD对气缸盖内冷却水流动及传热过程进行流固耦合模拟,分析并评价了该汽油机气缸盖的冷却性能,并针对冷却水套缸垫上水孔提出优化方案。结果表明,气缸盖温度分布不均匀,最高温差约137 K,缸盖水腔局部区域流动分布较差,鉴于此,依据正交设计方法提出了9种对缸垫上水孔尺寸及位置的优化方案,对比改进后的气缸盖温度场及流场结果,选择出最佳改进方案。改进后,水套内冷却水流动更好,冷却性能得到了改善,有效降低了气缸盖壁面的温度。

This paper took a high-speed marine gasoline engine cylinder head as a study object, utilized commercial CFD software and applied the method of FSI to simulate the flow and heat transfer phenomenon of cooling water, analyzed and evaluated the cooling performance of this gasoline engine cylinder head, based on the water holes of cylinder head gasket, proposed the optimization schemes.The results show that： the cylinder head temperature distribution is nonuniform, the maximum temperature difference is about 137 K, the flow distribution is poorer in the local area of cylinder head water cavity, for that reason, 9 optimization schemes are proposed according to the location and bore diameter of water holes of cylinder head gasket based on orthogonal design method, after compared with calculation results of temperature and velocity fields of each projects, choose the best improvement plan; after the improvement, the coolant flow distribution is better than before in the water jacket, the cooling performance is improved of water jacket, and the wall temperature of cylinder head is effectively reduced.