柴油机冷却水套内流场特性研究

Study on Flow Field Characteristics of Diesel Engine Coolant Jacket

为了全面了解柴油机冷却水套内部流场特性,基于计算流体动力学(CFD)模拟柴油机水套流场,分析冷却水套内流场特性,然后通过去除柴油机缸盖顶部结合压力试验验证模拟的正确性。结果表明:CFD模拟结果和实际流动特性基本相符,但出入口压力降比实际值偏小,且随流量增加,出入口压力损失实测值比计算值更大;水压在冷却水套内不同位置的损失率不同,最大压力损失是机油冷却器水套流入机体水套位置,占比达到52.5%,优化空间最大;冷却水套内部分区域存在死水区和漩涡区,影响流动,降低了冷却水套的冷却效率。

In order to fully understand internal flow field characteristics of diesel engine coolant jacket,flow field characteristics of diesel engine coolant jacket were analyzed based on computational fluid dynamics(CFD),and correctness of simulation was verified by removing top of diesel engine cylinder head combined with pressure test.Results show that CFD simulation results are basically consistent with actual flow characteristics,but pressure drop between inlet and outlet is smaller than actual value,and with the increase of flow,inlet and outlet pressure loss measured values greater than calculated value.Water pressure in the coolant jacket loss rate is different in different position,the pressure loss of oil cooler water jacket is biggest for water jacket,it accounts for 52.5%,optimization of space is the biggest.Dead water zone and vortex zone exist in some areas of coolant jacket,which affect flow and reduce cooling efficiency of coolant jacket.