Trajectory optimization method in two-stage-to-orbit RBCC-RKT launch vehicle

In view of the fact that the specific impulse and propellant mass flow rate of a rocket based combined cycle (RBCC) engine change constantly with flight conditions, a method based on augmented Lagrangian genetic algorithm for optimizing the trajectory of a RBCC-RKT two-stage-to-orbit (TSTO) horizontal takeoff launch vehicle is established when the aircraft aerodynamic parameters, the engine specific impulse and the maximum flying dynamic pressure are the constant values. The result shows that employed the method and given the range of flight program angle and propellant mass flow rate between a min and a max, the constraints can be satisfied and the history of flight program angle and propellant mass flow rate are optimized to provide a reference for the scheme demonstration and preliminary concept design of the vehicle.