多缸柴油机冷却水腔流动不均匀性的仿真研究

以多缸柴油机的冷却水腔为研究对象，使用Fluent软件对直列3、4、5、6缸柴油机冷却系统的流场进行仿真.结果表明:对于冷却水套进出水口在曲轴同一端的直列柴油机，从距离入口最近的缸到远离入口的最后一缸，各缸水套间通道压力逐渐降低，各缸缸盖进口和出口压力逐渐增加，各缸缸盖的流量逐渐降低.在相同入口流量条件下，随着发动机气缸数增加，总进口和总出口的压差逐渐降低，整个冷却水套的流动阻力减小，各缸缸盖进出口压差的平均值逐渐减小，发动机各缸盖中最大流量和最小流量之间的差值增加，发动机各缸缸盖流量的不均匀度大幅度增加. 

Simulation Study on Fluid Non-Uniformity of Multi-Cylinder Diesel Engine Cooling System

The cooling water system of multi-cylinder diesel engine was discussed with software Fluent to simulate the flow field of in-line 3、4、5、6-cylinder diesel engine.The results show that,for the cooling water jacket inlet and outlet in the same end of the crankshaft inline diesel engine,from the first cylinder near the inlet to the last cylinder remote from the inlet,the pres-sure of the inter-water channel of each cylinder is gradually reduced,the pressure of the inlet and the outlet of each cylinder head is gradually increased,and the flow rate of each cylinder head gradually decreases.At same inlet flow,the pressure difference between the inlet and outlet of each cylinder is gradually decreased with the increase of the cylinder numbers,the flow resistance of the entire cooling jacket is reduced,the mean value of the inlet and outlet pressure difference of each cylinder head gradually decreases,the difference between the maximum and minimum flow rate in each cylinder head of the engine increases,and flow non-uniformity of each cylinder head increases significantly.