Abstract: Weak coupling scheme in fluid-structure interaction simulation introduce lag error which may result in divergence of computation. The improved linear predict-correct scheme is able to eliminate the error and enhance computational stability, but there’re problems on prediction precision and computation cost. To improve the precision and to reduce costs, a new coupling scheme is proposed, which combines subcycling scheme and spline interpolation based predict-correct scheme. To indicate effectiveness of the scheme, a nonlinear supersonic panel flutter problem is numerically studied with linear predict-correct scheme and this new scheme. The results show that the new scheme is capable of reducing computing cost significantly while maintaining numerical stability. Also, the effect of number of spline points is studied. The results show that even less number of interpolation points is enough to keep computing accuracy.

Key words: Fluid-structure interaction, Panel flutter, Predict-correct scheme, Spline interpolation, Subcycling