收敛喷管的引射效应对背负式短舱温度影响研究

针对背负式发动机舱的工作条件,建立三维空气流动与传热的物理和数学模型。根据舱内结构和气流的流动特点,通过多面体网格技术和网格自适应技术进行区域离散化,采用标准k-ωSST湍流模型,对4种工况下喷管引射和无引射状态进行数值仿真,分析了舱内各典型特征截面的温度场分布、冷却气流流动情况。结果表明,发动机地面以最大状态开车时,对发动机舱的引射作用影响显著,附件工作区域温度值相比较无引射状态时低40℃左右,计算结果对发动机舱通风冷却系统设计提供一定的科学依据。

Research on the Influence of Convergent Nozzle Ejector Effect on Top-Mounted Nacelle of the Temperature Field

The physical and mathematical model of the 3D air-flow and heat transfer was set up for a certain type of aircraft knapsack nacelle working conditions. According to the structure and flow characteristics of the air chamber through the polyhedron grid technology and grid adaptation was applied to the region discretization. Using standard k-e turbulence model for three kinds of working condition of ejector nozzle under and no ejector numerical simulation, the nacelle of the typical characteristics of cross section temperature field distribution and the flow of cooling air flow conditions was analyzed. The results show that the engine at ground with maximum state to the nacelle when driving ejector function effect is remarkable, compared with the condition of no ejector, the engine accessories work area temperature was 40℃lower, the calculation results can provide certain scientific basis for the design of nacelle ventilation cooling system designed.