Synergistic optimization of precooling performance and compression performance for low-carbon precooled engine fueled with ammonia

Precooling technology is an effective way to increase the working Mach number of turbine engines. However, the current precooler design is mostly limited to the performance optimization of a single component, but fails to consider the overall efficiency of the precooling-compression system in a comprehensive manner, which results in the lack of a global optimization perspective. To this end, this paper proposes an optimization method for maximizing the outlet pressure of the precooling compression system based on the idea of synergistic optimization of precooling performance and compression performance. By calculation, the results indicate that there is a competitive relationship between the heat transfer performance and flow performance, which leads to a dual-influence mechanism on the precooling-compression performance. Besides, there are usually optimal values for precooler geometric parameters to achieve the best precooling-compression performance. Moreover, considering the engine performances, precooler weight and precooling temperature boundary, the compromise optimization results of precooler geometry parameters are obtained, showing that the specific thrust can be increased by 9.55 %, the specific impulse can be increased by 6.25 % and the precooler weight can be reduced by 4.66 %. The research in this paper is of great significance for guiding the design of high Mach number engine. • Optimization method considering precooling and compression performance is proposed. • A multi-objective optimization model for chemically pre-cooler has been established. • The competitive relationship between different performances is revealed. • The specific thrust and specific impulse can be improved by 9.55 % and 6.25 % respectively. • The weight of precooler can be reduced by 4.66 % after optimization.