飞机环境控制系统的最小熵增分析

Entropy generation minimization analysis for aircraft environmental control system optimal design

一种应用于飞机环境控制系统优化设计的新方法,以热力学第二定律为基础,运用熵增原理进行系统综合优化设计,分析了主要组成部件(热交换器和涡轮冷却器)以及座舱温度舒适性要求指标对系统熵增的影响.以某型飞机环境控制系统为例,通过数学建模和计算机仿真,获得了不同结构参数下,系统运行在最小熵增状态时的引气与供气参数优化匹配结果.研究表明,提出的最小熵增分析方法对未来复杂飞机环境控制系统的综合设计具有重要的指导意义.

A new method bases on the second law of thermodynamics for entropy generation minimization analysis and thermodynamic optimization in the research and design of aircraft environmental control system （ECS）. The chosen example is a military aircraft ECS with an air cycle machine （ACM） and a counter-flow heat exchanger. The effect of some design features for ECS entropy generation was discussed, such as the efficiency of heat exchanger and turbine in ACM, the air steam pressure and temperature of bleed from air-fighter engine compressor, and the air temperature of delivery to the cabin and comfort the pilot. Numerical results show that the temperature of the air stream that the ECS delivers to the cabin can be optimized for system operation at minimal entropy generation, when the components geometry parameters are fixed. The method illustrated is applicable to more complex and realistic aircraft environmental control systems.