Two-dimensional simulation method for shock tube diaphragm rupture process based on overlapped dynamic grids

Abstract

The invention discloses a two-dimensional simulation method for a shock tube diaphragm rupture process based on overlapped dynamic grids. According to the two-dimensional simulation method for the shock tube diaphragm rupture process based on the overlapped dynamic grids, initial grids are established for a shock tube and a diaphragm respectively, the problem of grid hole breaking under the wall surface crossing condition is solved by setting special boundary conditions, the diaphragm deformation mode is defined as arc bending type deformation, and dynamic grid simulation is carried out on the rupture process of the diaphragm, so that dynamic CFD simulation of the movement process of the diaphragm can be realized. Compared with an existing main ideal diaphragm rupture analysis method, the two-dimensional simulation method for the shock tube diaphragm rupture process based on the overlapped dynamic grids better conforms to physical reality, the obtained simulation result is more accurate and feasible, and the effect of researching the flow problem of a shock tube and a shock tunnel is obvious.

Description

technical field [0001] The invention belongs to the technical field of hypersonic wind tunnel tests, and relates to overlapping grids and dynamic grid deformation control in the technical field of dynamic grids in CFD (Computational Fluid Dynamics), in particular to shock tubes based on overlapping dynamic grids A two-dimensional simulation method for diaphragm rupture process. Background technique [0002] CFD (Computational Fluid Dynamics) is one of the important means to carry out fluid dynamics research, and it plays an increasingly important role in the research involving the flow process of fluid medium and its influence. In computational fluid dynamics CFD, a typical shock tube generally consists of a section of high-pressure gas, a section of low-pressure gas and a diaphragm that isolates them. The flow process of the shock tube refers to the flow of gas in the tube within a period of time after the diaphragm ruptures. process. CFD discretizes the continuous flow f...

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Problems solved by technology

[0003]The dynamic process of the rupture of the diaphragm in the shock tube and the shape of the diaphragm itself have a great influence on the flow in the tube and the airflow in the experimental section. The analysis method of the ideal membrane rupture method adopts The CFD simulation without grid deformation treats the rupture process of the diaphragm as an instant disappearance, which cannot reflect the influence of the diaphragm movement and diaphragm shape on the flow field. The shock wave velocity obtained in this way is obviously higher than the actual one, which leads to the simulation It is quite different from the real physical process

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