Improved time-marching technique for solving aeroelastic equations

In the control equations of aeroelastic problem, the structural block is marched by the standard Runge-Kutta method, the generalized aerodynamic loads are computed by interpolated method and an approximate 4th order Runge-Kutta marching method in which it only needs to compute the aerodynamic loads once per each time step is developed. By solving the non-linear Bernoulli equation and computing the aeroelastic responses of a supersonic wing, the precision of the approximate method is found to be much higher than the 4th order Runge- Kutta method in which the aerodynamic loads are frozen and the computed results are very close to those by the standard Runge-Kutta method while the improved approximate method only needs quarter times of employing the aerodynamic solver comparing with the standard Runge-Kutta method. So the efficiency of the aeroelastic numerical simulation is greatly improved. For the common aeroelastic problem, only 20-30 time steps in one period is necessary to ensure a quite good time precision.