Modeling and simulation coupled aerodynamics, constraint force and flight dynamics for stage separation of aircraft

Modeling and simulation for stage separation of an aircraft mainly contains three parts: flight dynamics module, constraint force module and aerodynamics module. The three parts are coupled, and make the problem difficult to solve. To address this problem, a coupling modeling method was proposed. This method includes: flight dynamics equations of motion, using constraint force equation (CFE) method to solve constraint forces, using computational fluid dynamics (CFD) method to solve aerodynamics load, and impact analysis. The aerodynamics load calculated by aerodynamics module enters the constraint force module as input, the velocity and angular velocity of the vehicle can be obtained from the constraint force module, and input the flight dynamics module. Then the location and attitude can be determined. After that, the velocity, location and attitude information return to the aerodynamics module as feedback to complete a loop. The impact analysis module gives the order when to stop the simulation.