Prediction of the Stability Derivatives Using 3-Dimensional Euler and RANS Computations

초록

In this paper, the stability derivatives for the Standard Dynamic Model(SDM) are estimated using computational fluid dynamics(CFD). The governing equations used in this study are the three-dimensional Euler and Reynolds-averaged Navier-Stokes(RANS) equations. Harmonic oscillations are applied to compute pitch damping derivatives, and a dual time stepping method is applied to evaluate time-accurate solutions. Roll damping derivatives, on the other hand, are evaluated by a steady state method in a non-inertial body fixed frame. Source terms due to the transformation of the governing equations to the non-inertial coordinates are added for the steady state method. Simulations are performed at various flight conditions in terms of Mach numbers, angles of attack, and oscillation amplitudes. In addition, the results of Euler and RANS computations are compared.