Analysis of factors affecting uniformity of engine coolant flow rate

Abstract Aiming at the short service life of an engine cooling water sleeve caused by uneven heating, the CFD model is established using STAR-CCM+ software, and the flow field simulation in the cooling water sleeve is completed. Based on this premise, the orthogonal test design method is employed to investigate the effects of cross-section size and allocation of cylinder holes in various areas of the cooling water sleeve on the uniformity of coolant velocity. The results show that the cylinder holes near the thermostat outlet have the most significant impact on the coolant velocity uniformity, followed closely by the cylinder holes near the coolant inlet and, finally, the cylinder holes near the EGR cooler outlet. Furthermore, it is observed that the uniformity of the velocity increases with the decrease of the cross-section areas of the cylinder holes located near the thermostat as well as the EGR coolant, with the increase of the cross-section areas of the cylinder holes near the inlet, which decreases firstly and then increases later. The study results hold substantial reference value for optimizing this engine’s cooling water sleeve structure.