Optimization of a Reverse-Brayton cycle with inter-cooling and regeneration

Abstract

A Reverse-Brayton cycle represented by the B787 electrical driven environmental control system is used as the analysis object, including the thermodynamic process of two-stage compression, intercooling, and regeneration. An analytical expression for the thermodynamic performance of the cycle is derived based on the endoreversible thermodynamic analysis model (ETM). Combined with a genetic algorithm, an ETM-based optimization approach (ETM-OA) is proposed. Using this method, it is found that the coefficient of performance is increased by 34.1 % and 48.4 % under two typical flight conditions, respectively, and the corresponding system entropy generation number is reduced by 30.2 % and 51.1 %, respectively. Both ETM-OA and entropy generation analysis show that the electric supercharging module, secondary heat exchanger, and air cycle machine are key components of the system. This study provides a convenient method for obtaining the thermal power conversion mechanism of complex thermal cycles and conducting optimization analysis.

Keywords

• Reverse-Brayton cycle
• Endoreversible thermodynamic analysis method
• Genetic algorithm
• Thermal optimization
• Entropy generation