襟翼偏转翼伞气动性能数值模拟分析

Numerical simulation analysis for aerodynamic performance of parafoil with flap deflection

摘要:

为研究襟翼偏转对翼伞气动性能的影响，对不同襟翼偏转情况分别建立CFD模型，通过有限体积法进行空间离散并求解RANS方程，模拟翼伞在转向与雀降阶段的气动性能，进而结合最小二乘法进行参数辨识，实现翼伞气动模型的修正.模拟结果表明:襟翼偏转会引起翼伞压强分布改变，失速迎角减小，升阻力系数突增，对翼伞气动性能造成复杂的影响; 修正的翼伞气动模型可以较好描述翼伞气动性能与襟翼偏转的变化规律，相比传统气动模型有效地提高了计算精度，为翼伞在转向与雀降阶段的精确建模提供参考.

Abstract:

To investigate the effect of flap deflection on aerodynamic performance of the parafoil, CFD models are established for different flap deflections. By using the finite volume method, the spatial discretization is carried out and the RANS equation is solved. The aerodynamic performance of the parafoil in the stage of turning and flaring is simulated, and then combining with the least square procedure, parameter identification is carried out to implement the modification of the parafoil aerodynamic model. Simulation results show that the flap deflection can cause the change of the parafoil pressure distribution, the decrease of the stall angle of attack, the sudden increase of the lift drag coefficient, and the complex effect on aerodynamic performance of the parafoil. Compared with the traditional aerodynamic model, the modified parafoil aerodynamic model can better describe the regulation of the flap deflection and the aerodynamic performance of the parafoil, and the calculation precision is improved effectively. It provides a theoretical reference for precise modeling of the parafoil in the stage of turning and flaring.