Modified aerodynamic coefficient models of hypersonic vehicle in reentry phase

The aerodynamic coefficients model of hypersonic vehicle in reentry phase and parameters identification are considered. The relationships between the aerodynamic coefficients and main factors including angle of attack and Mach number are analyzed based on the public aerodynamic coefficients database. The modified lift and drag coefficients models are built and the parameters of the models are identified by the nonlinear least square method. The comparisons between the database and the value by the modified aerodynamic coefficients models show that the averages of the relative errors are all less than 5.10%, which demonstrates that the modified aerodynamic coefficients models have the high precision and can be used in reentry trajectory optimization and simulation.