MPS方法模拟三维圆柱形液舱晃荡问题

[目的]为了研究在单自由度横荡激励下,激励频率对液舱晃荡现象的影响,将移动粒子半隐式(MPS)方法应用于水平圆柱形液舱晃荡问题。[方法]基于改进的MPS方法和GPU并行加速技术,课题组将自主开发的无网格粒子法求解器MPSGPU-SJTU应用到三维圆柱形液舱晃荡问题中。首先,进行模型验证,对激励频率为一阶固有频率时的晃荡现象进行模拟。然后,在此基础上进行不同激励频率下的晃荡现象计算,并将激励频率在1.2 Hz的模拟结果与实验结果进行对比。最后,在此基础上模拟不同激励频率下液舱的横荡运动。[结果]结果显示,M PSGPU-SJTU求解器能够较好地模拟圆柱形液舱内的液体晃荡现象,也能较为精确地计算液舱受力;当激励频率在固有频率附近时,晃荡现象十分剧烈,当远离固有频率时,晃荡会迅速变弱,液舱受力也随之迅速减小。[结论]所得模拟结果能够为圆柱形液舱的设计应用提供有效参考。

CFD simulations of three-dimensional violent sloshing flows in tanks based on MPS and GPU

For violent sloshing,the flow field becomes complicated and 3-D effect is non-negligible.In addition to the excitation direction,the wave can also propagate perpendicular to the excitation direction.Due to the superposition of waves from different directions,the impact pressure imposed on the wall of the tank may increase.In this paper,our in-house solver MPSGPU-SJTU based on moving particle semi-implicit(MPS)method coupled with GPU techniques is employed for the liquid sloshing simulation,to study the factors leading to the 3-D effect.Firstly,a series of sloshing simulations are carried out to validate the reliability of present solver.Then,the sensitivity of 3-D effect against some parameters,such as excitation frequency,dimensions of the tank and filling ratio,is checked through numerical simulations.Time histories of pressure obtained by 2-D and 3-D simulations are compared to judge the occurrence of 3-D effect.It concludes that effects of those parameters are all significant.

基于GPU加速的MPS方法模拟三维急弯河道溃坝流动

溃坝流动是一种灾害性的复杂流动现象,该文将GPU加速技术与MPS方法相结合,采用该课题组自主开发的MPSGPU-SJTU求解器对三维急弯细长河道中的溃坝流动问题进行了数值模拟。监测河道中轴线处自由液面水位高度与速度场分布情况表明,数值模拟结果与实验结果吻合较好。此外,该文对比了CPU与GPU的计算时间,验证了采用GPU并行技术可以大幅提高MPS方法计算效率。还改变了初始流场的水位高度,计算三种不同工况下溃坝流动过程,同时在河道壁面布置压力监测点预报河道壁面所受的砰击压力,评估溃坝流动的危害。