液氢预冷吸气式发动机建模与循环特性分析

To study the cycle characteristics of a pre-cooled engine, liquid hydrogen pre-cooled air-breathing engine (LHPE) with simple structure and low matching difficulty was proposed. The thermodynamic cycle process of LHPE was analyzed, and the similarities and differences with Air Turbo Ramjet with Expander Cycle (ATREX) in the cycle process were compared. Based on the modeling method of component-level, a general method of user-defined component calculation sequence was proposed, which solves the sequential calculation problem of the heater's hot side and cold side. A simulation model of LHPE was constructed and the influence of cycle variables on the overall performance of LHPE was calculated. The results show that compressor pressure ratio and fuel flow rate have a significant impact on overall performance, and turbine inlet temperature mainly affects parameter selection of fuel flow path at design point. Along the flight trajectory, net thrust at low Mach number increases by increasing design value of compressor pressure ratio and fuel flow rate, and power load of turbine increases when design value of compressor pressure ratio increases, while specific impulse increases by more than 10% when design value of fuel flow rate is reduced by 15%. Specific impulse can slightly increase, and power load of turbine can be significantly decreased by increasing turbine inlet temperature. LHPE has a greater specific impulse advantage compared with ATREX and Pre-cooled Turbojet (PCTJ).