双缸发动机冷却水套流场分析及优化

Flow Field Analysis and Optimization of the Two Cylinder Engine Water Jacket

为评估某双缸发动机冷却水套结构设计的合理性,对该双缸发动机冷却水套开展了CFD流场数值模拟分析,结果表明:原冷却水套结构下存在极少冷却液流向第二缸缸体及其缸头上鼻梁区的现象,导致两缸冷却液流速差异明显,不利于两缸的均匀冷却。对缸体入水口和缸垫上水孔进行了改进,改进后冷却液从缸体入水口进入后可同时向两缸分散流动,促使缸体水套各缸的冷却液流速分布更均匀;第二缸缸头上鼻梁区流速明显增加。研究结果可为双缸发动机冷却水套冷却液流速分布的合理性评估及水套结构改进提供仿真数据支撑及理论指导。

In order to evaluate the rationality of the design of the cooling water jacket structure for a double-cylinder engine,CFD analysis on flow field of this double-cylinder engine cooling water was conducted.The results showed that there was very little coolant flow to the second cylinder block and its upper nose area under the original cooling water jacket structure,resulting in a significant difference in coolant flow velocity distributions between the two cylinders,which was not conducive to uniform cooling of the two cylinders.The modification was made on the coolant inlet of cylinder block water jacket and the water holes on the cylinder gasket.After the improvement,the coolant could flow dispersedly to both cylinders simultaneously after entering the cylinder block inlet,ensuring better uniformity of the coolant velocity distribution of each cylinder block water jacket.The coolant flow velocity in the upper nose bridge area of the second cylinder head significantly increased.The research results can provide simulation data support and theoretical guidance for the rationality evaluation of the coolant flow velocity distribution and the improvement of the water jacket structure of the double-cylinder engine cooling water jacket.