基于三维CFD技术的发动机冷却水套流动分析

Flow Analysis in Cooling Water Jacket of Engine Based on Three Dimensional CFD Technology

利用计算流体力学软件对发动机冷却水套流动进行了三维数值模拟研究。研究结果表明:平均流速大于0.5 m/s时,气缸体水套内表面的上部平均流速和换热系数均比下部高;缸盖火力面冷却效果较好,换热系数高于10 kW/(m2.K),流速大于1.0 m/s,但冷却效果欠均匀;总压力降为38.2 kPa;上水孔的布置和尺寸使缸盖下层的各火力面有较好的冷却效果。

A computational fluid dynamics （CFD） software was utilized to study the fluid flow in the cooling water jacket of an engine. The results show that mean flow velocity in cylinder block water jacket is higher than 0.5 m/s, the flow velocity and the heat transfer coefficient of top area is higher than that of bot- tom area in cylinder block water jacket; the fire deck of cylinder head has a better cooling effect, its heat transfer coefficient is higher than 10kW/（m2 ＂K） and the flow velocity is more than 1.0 m/s, but the cooling effect appears as a nonuniformity. Total pressure loss through water jacket is 38.2 kPa; the position and size of water inlet holes can ensure better cooling effect of the fire deck at bottom of cylinder head.