Modeling of hydrogen engine parameters design during flight to orbit of reusable launch vehicle

In order to investigate the influence of hydrogen engine parameters on launch vehicle performance, the mathematical models suited for single stage to orbit reusable launch vehicle flight process were brought up based on hydrogen engine performance parameters, including rocket motion equations, flight control conditions and vehicle mass model. The vehicle mass variety rules were discussed in detail changed with hydrogen engine mixture ratio during flight to orbit. The results show that on the condition the vehicle gross mass set, when hydrogen engine mixture ratio increases from 4 to 14, propellants mass and engine mass decrease firstly and then increase, tank mass decrease all the time, which synthetically bring forth payload mass increase firstly and then decrease.