Overall Performance Modeling and Performance Analysis of Hydrogen Precooled Turbine Engine

Abstract

This paper introduces the calculation model of turbine engine heat exchanger and component characteristics. Then establishes a calculation model for the overall performance of a hydrogen-cooled turbojet engine, and introduces the calculation methods of design point as well as off-design point characteristics. Appropriate design point parameters are selected through cyclic analysis. The effect of hydrogen precooling on turbojet engine performance and the extension of the flight envelope are analyzed through an overall performance calculation model. The analysis shows that hydrogen precooling has a low impact on specific thrust (6% increase in specific thrust compared to a turbojet without precooling), but has a significant impact on air flow, thereby improving the thrust performance of the turbojet engine. Analyze the effect of different hydrogen precooler outlet temperatures on engine performance through comparison. The results show that hydrogen pre-cooling makes the compressor work at a high-performance point (corrected-speed above 80%) by cooling the incoming air, thus ensuring the thrust performance of the turbojet engine at high altitude and high speed(climbs along the constant dynamic pressure with 50kPa accelerate to M4). The lower precooler outlet temperature is beneficial to the increase of engine thrust. For example, the precooler outlet temperature decreases by 40K and the engine thrust increases by about 21%. Considering the amount of hydrogen used and the engineering application, it is difficult to choose an excessively low precooler outlet temperature, the paper simply analyzes that the selection of 360K is the appropriate precooler outlet temperature.