SUV发动机舱的温度场和热流场仿真模型及其改进方案

Temperature Field and Heat Flow Field Simulation Model and Improvement Scheme of SUV Engine Compartment

某型SUV在中低速和高速爬坡工况下发动机会处于功率高值,冷却出水温度也偏高。为此采用STAR CC M+和KULI软件分别建立SUV发动机舱的温度场和热流场仿真模型,获得发动机舱在选定工况下的温度流场、进气、进出水温度等热平衡评价指标。针对机舱内部冷却系统存在的前端气流泄漏和内部回流等设计风险提出改进方案,并进行三维流体和一维温度联合仿真。后续样车阶段的整车热平衡试验结果证明了改进方案的有效性和联合仿真分析的置信度。

The engine of a certain SUV will be at a high power value and the temperature of the cooling water is also high under medium-low speed and high-speed climbing conditions.With STAR CCM+and KULI software,the temperature field and heat flow field simulation models of SUV engine compartment were established,and the thermal balance evaluation indexes such as temperature flow field,inlet and outlet water temperature of engine compartment under selected working conditions were obtained.Accordingly,an improvement scheme was proposed for the design risks such as front-end airflow leakage and internal backflow existing in the internal cooling system of the engine room,and three-dimensional and one-dimensional co-simulations were carried out.The results of vehicle thermal balance test in the subsequent sample stage prove the effectiveness of the improvement scheme and the confidence of the co-simulation analysis.