航空发动机面式空气滑油散热器的性能分析

为了改进航空发动机在地面停机、起飞滑跑等工况下散热能力差的问题，利用发动机进气道作为传热表面设计了一款面式空气-滑油散热器，并基于4分块、7分块、直平面代替弧面等分区模拟的方法开展了其传热特性研究及分块模拟的等效性分析. 研究结果表明:采用4分块、7分块以及直平面代替弧面等条件下散热器和滑油温度分布及变化趋势都基本相似，且温度差都在1 K以内，通过滑油侧与空气侧计算出的单元散热器散热量偏差也都在5%以内；采用分区模拟进行大型面式散热器的散热特性分析以及采用“以直代曲”等方法模拟弧长与直径比在0.203以下的弧面具有可行性和可靠性. 

Heat Dissipation Characteristics Analysis of Surface Air-Oil Heat Exchanger Applied in Aircraft Engine

In order to enhance aircraft engine heat transfer performance in the conditions of ground idle speed or low flying speed, a surface air-oil exchanger was presented using air inlet passage as its dissipation area. Its heat dissipation characteristics, as well as districted simulation equivalence, were investigated through the studies of 4 districted mode, 7 districted mode and the mode of using flat surface to replace arc surface. The numerical results demonstrate that temperature distributions in air side are almost the same in the cases of 4 districted mode, 7 districted mode and the mode used flat surface to replace arc surface in the simulations. All of their temperature differences are smaller than 1 K, and the discrepancies of calculated heat dissipation power are below 5%. The phenomena of heat transfer in oil side are also the same in the three cases. The research validates the feasibility and reliability of the methods of using districted simulation and using flat surface instead of arc surface where the ratio of arc length to diameter is below 0.203, when analyzing thermal characteristics of a large surface heat exchanger.