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运用非定常Navier-Stokes(N-S)方程有限体积算法及非结构动网格技术对X-37B飞行器着陆流场进行数值模拟,比较了飞行器在拖挂阻力伞和不拖挂阻力伞两种情况下的流场差异.模拟以混合网格有限体积方法为基础,控制体方程采用N-S方程组,流场计算空间离散采用格点格式,通量计算格式采用Roe,时间离散采用LU-SGS理论和二阶时间精度的双时间步长,湍流模型采用两方程SST湍流模型.动网格技术采用线性弹簧理论处理阻力伞在摆动时流场的变化.阻力伞模型采用中间带气孔的C-9圆锥型降落伞外形,但规模有所缩小,以便适应飞行器.模拟比较了两种情况下着陆流场的差别,并主要比较了两种情况下阻力的差别,从而证明飞行器在拖挂阻力伞的情况下更容易减速着陆.
The unsteady Navier-Stokes (NS) equation finite volume algorithm and the unstructured moving grid technique are used to simulate the landing flow field of X-37B aircraft. The comparison of the aircraft landing drag towing drag umbrella and drag drag umbrella Based on the finite volume method of mixed meshes, the governing equations are NS equations, the spatial discretization of the flow field adopts the lattice format, the flux calculation formula adopts Roe, the time dispersion adopts the LU-SGS theory and the second The two-step SST turbulence model is adopted for the turbulence model and the linear spring theory is used to deal with the variation of the flow field during the dragging of the drag umbrella. The drag umbrella model uses the C-9 conical The shape of the parachute, but reduced in size, in order to adapt to the aircraft.The simulation compares the difference of the landing flow field in the two cases and mainly compares the difference of the resistance in the two cases to prove that the aircraft towing the umbrella in the case of drag Easy to slow down landing.