A modified loosely-coupled algorithm for calculation of wing rock

A modified loosely-coupled algorithm is provided for numerical simulation of wing rock. The algorithm combines the explicit and implicit formulas to calculate the dynamics equations and to update girds, improving the temporal convergence and numerical stability, being able to obtain reasonable results with larger time steps. Through analyzing the conventional loosely-coupled algorithm, it is found that if the implicit methods are used to calculate the angular rate and angle, the aerodynamic moments have a large time-lag than motion due to the time-lag of grid. Therefore, the amplitudes of wing rock obtained are larger than experimental values at larger time steps. By contrast, the amplitudes using explicit methods are smaller at larger time steps. By calculating wing rock of swept delta wing being 80°, the feasibility of the modified loosely-coupled method is verified.