用非结构动网格技术计算确定再入飞行器配平攻角

提出了用数值计算直接确定飞行器配平攻角的自由振动法.该方法采用非结构动网格技术,使飞行器在气动力作用下绕通过质心的轴线自由振动,最终衰减到配平攻角.构造了一种MUSCL类型有限体积格式,求解考虑了动网格效应的三维非定常Euler方程,采用弹簧近似技术实现非结构网格的变形运动.作为例证,计算确定了载人飞船返回舱的配平攻角,计算结果与实验结果接近.该方法外形适应能力强,效率较高,具有较好的应用前景.

Numerical determination of trim angle of attack for reentry vehicles using dynamic unstructured grids

A free-oscillation method to directly determine the trim angle of attack for space vehicles via CFD strategy was developed. In this new method, dynamic unstructured grid technique is used, the vehicle is allowed to oscillate about an axis passing through its center of gravity under the function of aerodynamic forces, and finally the oscillation declines to stopping at trim angle of attack. A MUSCL type finite volume scheme was constructed to discretize the 3D unsteady Euler equations described in ALE frame. The deformation of unstructured grid was implemented by spring analogy. As a demonstration, the trim angle of attack of a reentry capsule was determined. Calculation result agrees well with experiment data, which shows that the method has the potential to handle complex geometries and is relatively more efficient and can be widely used in spacecraft design process.