关键词: 外挂物分离, 并行计算, 非定常, 动态重叠网格, 多重网格

Abstract: The development of concurrent engineering has generated a new concept of computational fluid dynamics, and based on this a new integrated system of numerical simulation is developed which takes unsteady flow computation as its core. Using moving overlap grids, the system can compute the flow field of objects undergoing large overall motions, and can simulate motion under the effect of aerodynamic loads, gravitation and launch force based upon the 6-degree-of-freedom motion equations. As the simulation of store separation is characterized by moving grids and time accuracy, this research studies grid rebuilding and multigrid methods to improve the computation effectiveness, and achieves high efficiency under parallel environment. In the case of 20 central processing units (CPU), the parallel computation and 3-level multigrids shorten the running time by 40 times. The newly developed code is validated by the simulation of calibration test of store separation from wing. The computational results are basically consistent with the testing data in the first half second. As for the deviation that appears in the latter stage of separation, the time history of the aerodynamic loads is discussed in detail, and the yawing moment error and the accumulation effect are considered to be the main cause. Fortunately, for the key first half second in the separation process, the simulation system achieves comparatively high efficiency and accuracy.

Key words: store separation, parallel computation, unsteady, moving overlap grids, multigrids