冷却液流动均匀性对缸套热变形的影响研究

对某一高压共轨柴油机的冷却液流动特性和缸盖、缸套关键点温度进行了台架测试,为热分析提供边界条件;建立了缸盖-缸套-冷却水-机体流固耦合模型,应用流-固耦合传热方法,研究了冷却液流动均匀性对缸套热变形的影响,并优化了机体分水孔和缸盖上水孔的流动特性。结果表明:优化后的水套,各缸冷却不均匀性系数平均减小了9.78%;缸盖水套最高温度下降了8.64%,缸套最高温度下降了2.03%,缸套热变形最大值减小了1.10%。

Study on the Influence of Coolant Flow Uniformity on the Thermal Deformation of Cylinder Liner

The coolant flow characteristics and the temperatures of the key locations of cylinder head and cylinder liner in a high?pressure common rail diesel engine are measured on test bench to provide the boundary con?ditions for thermal analysis.The fluid?solid coupling model for cylinder head,cylinder liners,coolant and cylinder block is established and the effects of coolant flow uniformity on thermal deformation of cylinder liner are studied by applying fluid?solid coupling heat transfer method,with the coolant flow characteristics in the water distribution holes of cylinder block and in the water holes of cylinder head are optimized.The results show that the cooling un?evenness coefficient in optimized water jacket is reduced by 9.78%on average,the highest temperature of the water jacket in cylinder head and cylinder liner is lowered by 8.64%and 2.03%respectively,and the maximum thermal deformation of cylinder liner is decreased by 1.10%.