王琪，黄万友，连福新，孙鹏，于明进

(山东交通学院 汽车工程学院，山东 济南  250023）

    摘要：随着发动机工作温度越来越高以及发动机舱内布置越来越紧凑、拥挤，发动机舱散热性能面临了更大挑战。本文利用GAMBIT软件建立发动机舱CFD模型、生成计算区域网格、设置边界条件，利用FLUENT软件对汽车在30km/h速度下发动机舱温度场进行仿真，得到发动机舱的温度场分布和冷却气流流速及方向变化规律。仿真结果表明发动机舱顶部和尾部温度较高，最高温度出现在发动机排气歧管周围；发动机舱内不同位置冷却气流速度差异很大，介于车速的0.25~1.7倍之间。

    关键词：发动机舱；温度场；冷却气流

            Abstract: With the engine operating temperature becoming more and more higher, layout becoming more and more compact and crowded inside the engine compartment, maked the engine cabin cooling performance face greater challenges. In this paper, nacelle CFD model was established by using software GAMBIT, grid computing area was generated and the boundary conditions was set. The simulation was studied by using software FLUENT for car engine compartment at the speed of 30m/s. The nacelle high temperature parts, cooling airflow velocity and direction was found. The results showed that the temperature at the near of the top and tail nacelle was higher, the highest temperature appeared at the around of the engine exhaust manifold; The difference of the cooling air speed was very big in differert positions of engine nacelle, it was the vehical’s speed from 0.25 to 1.75 times.

    Key Works: Engine Nacelle; Temperature Field; The Cooling Air