摘要
A high precision and novel modeling method, to identify the aerodynamic parameters of the parafoil based on CFD(Computational Fluid Dynamics) is proposed. By solving the governing equations and the k-ε equations, the effects of leading edge incision of the parafoil on aerodynamic performance and stability are investigated. It is concluded that increasing the length and slope of the leading edge incision can decrease the lift coefficient and increase the drag coefficient, the stall angle of attack and lift to drag ratio are also decreased. The slope angle and the length have different effects on aerodynamic performance of the parafoil. Increasing the length affects the pressure distribution of the upper and lower wing surface. Increasing the slope leads to airflow separation at the trailing edge of the parafoil. Then, the variation of lift coefficients with time is obtained by adding different types of wind into the flow field on the basis of field velocity approach. By comparing the flow field of different models, it can be found that reducing the incision length and the slope are beneficial to enhance the stability of the parafoil.
A high precision and novel modeling method, to identify the aerodynamic parameters of the parafoil based on CFD(Computational Fluid Dynamics) is proposed. By solving the governing equations and the k-ε equations, the effects of leading edge incision of the parafoil on aerodynamic performance and stability are investigated. It is concluded that increasing the length and slope of the leading edge incision can decrease the lift coefficient and increase the drag coefficient, the stall angle of attack and lift to drag ratio are also decreased. The slope angle and the length have different effects on aerodynamic performance of the parafoil. Increasing the length affects the pressure distribution of the upper and lower wing surface. Increasing the slope leads to airflow separation at the trailing edge of the parafoil. Then, the variation of lift coefficients with time is obtained by adding different types of wind into the flow field on the basis of field velocity approach. By comparing the flow field of different models, it can be found that reducing the incision length and the slope are beneficial to enhance the stability of the parafoil.
引文
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