薄平板气动导数的数值计算

Numerical Assessment of AerodynamicDerivatives of Thin Flat Plate

用基于一般曲线坐标系和交错网格的差分法求解原始变量二维不可压粘性流体的Ｎ－Ｓ方程，计算了宽高比为２２．５、两端圆滑的薄平板的气动导数．将薄平板当作刚性物体，首先分别计算物体做竖向强迫振动和扭转强迫振动的气动力，雷诺数取为１０５，物体运动和气流的耦合作用用动网格法考虑，Ｎ－Ｓ方程用二阶投影法和多重网格法求解．然后用最小二乘法确定Ｓｉｍｉｕ和Ｓｃａｎｌａｎ给出的气动力表达式中的８个气动导数．

Numerical assessment of aerodynamic derivatives of a thin flat plate is conducted by solving two-dimensional initial variable incompressible Navier-Stokes equations in general curvilinear coordinates and staggered mesh with finite difference method. Aerodynamic forces on the heaving or torsional oscillated rigid plate are computed with Reynolds number of 10 5. Vibration of the body is accounted by the moving mesh method. The second-order project method coupled with multigrid technique is used to solve N-S equations. Aerodynamic derivatives in Simiu and Scanlan's formulation of aerodynamic forces are calculated using the least square method. The most aerodynamic derivatives of the thin flat plate obtained with present method agree quite well with both Theodorsen's theoretical results and wind tunnel testing results.