气候实验室发动机尾气小引射比降温排放特性研究

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中图分类号：V211.3 文献标志码：A文章编号：1000-4939（2025）03-0534-08

Abstract：The objective of this paper is to study the influencing factors and laws regarding the cooling and emission of engine exhaust with a low entrainment ratio in a climate laboratory.For a typical engine with a small bypass ratio，a numerical simulation method is adopted，taking into account the composition of the engine's tail gas and the variable-specific heat properties of the fluid. The influences of the exhaust pipe diameter，the distance of the pipe inlet，and spray cooling on the emisson characteristics of engine tail gas with alow entrainment ratio are analyzed.The simulation results show that the entrainment ratio is linearly related to the exhaust pipe diameter and increases as the pipe diameter increases.The distance of the pipe inlet has relatively litle influence on the entrainment ratio，yet there exists an optimal value for it. Spray cooling disrupts the surge structure of the entrainment flow field，reducing the velocity loss of the tail-gas jet and increasing the entrainment ratio.

Key words：climate laboratory；engine driving；variable specific heat fluid properties；entrainment ratio; water spray cooling

飞机气候环境实验室是检验飞机承受环境作用能力的重要手段之一，它通过在室内模拟高温、低温、淋雨、降雪、雷电等自然气候环境对飞机进行极端气候条件下的环境适应性考核，包括不需要发动机运行的静态试验和发动机开车运行时的动态试验[1]。（剩余10479字）