SPH方法研究空气在平板入水中的影响

飞机水上迫降以及船体在高速行驶时,均会发生结构物砰击水面的现象,当结构物底面较为平坦,砰击水面时会捕获空气,在板底形成空气垫。研究空气垫的形成及影响,有助于对结构物进行更准确的载荷分析。该问题的研究涉及到气固液三相的相互作用,在数值模拟中仍是一个挑战,本文使用光滑粒子流体动力学(SPH)方法对该问题进行模拟。首先,与实验结果进行对比;其次,系统地研究了平板形成空气垫以及砰击水面的过程,考查了空气、水和平板的动能变化。对比了在SPH模拟中考虑空气与不考虑空气得到的水压力场和平板所受压力,说明了空气对结果的影响;最后,研究了平板宽度对空气垫形成的影响,从而进一步影响加速度。

Research on the effects of air during flat plate impacting with water using SPH method

The air cushion produced by the interaction of flat bottom structures and fluids is a practical problem,which happens on a moving body such as airplane or ship hitting water.Research on the formation and effects of air cushion improves the accurate measurement of loads on structures,which is a challenge in simulation because it is the interaction among air,water and solid. In this paper,smoothed particle hydrodynamics (SPH) method is used for the simulation.First of all,the SPH simulation results are compared with experimental results. Then,the processes of air cushion formation and impact with water are described carefully.The kinetic energies of air,water and plate are analyzed.Pressure field of water and pressure on the plate show the effects of air,based on the comparison between with-air and without-air SPH simulation.The influences of plate width on the formation of air cushion and acceleration are investigated in the end.