Basset力研究进展与应用分析

Progresses and Applications of Basset Force

Basset力为两相流中颗粒与流体存在相对加速度时所产生的一种非恒定气动力 ,以往对其进行了大量的实验研究、理论分析和数值模拟。本文通过对Basset力研究文献的综述 ,分析并归纳了各种不同两相流动问题中该力的影响情况 ,得到的结论是 :对于气泡在液体内的流动问题 ,当气泡运动的脉动频率很大或很小时可以忽略Basset力对其运动的影响 ;对于固体或液体颗粒在气体中的运动问题可以忽略Basset力的影响 ;而其它两相流动问题则需要根据具体问题的特点来决定是否考虑Basset力的影响 ,其中需要考察 :流体与颗粒密度差别 ,颗粒尺寸 ,流动特征时间和颗粒运动弛豫时间 ,相对加速度 (或减速度 )等因素。本文还探讨了Basset力研究的发展方向。

Basset force is an unsteady force on a particle due to acceleration of relative velocity between particle and fluid. Different authors have carried out a lot of experimental, theoretical and numerical investigations. Investigations on Basset force are reviewed and summarized in the present paper. For different types of two phase flow, there are some characteristics estimating Basset force on a particle. For the bubble liquid two phase flow, the Basset force can be neglected when the perturbation frequency of the fluid flow is small or large value. For liquid (or solid) particle gas two phase flow, neglecting Basset force is reasonable. But for other two phase flows, the magnitude of Basset force is determined by some actual conditions, such as the particle size, ratio of the fluid density to the particle, the flow characteristic time and the relaxation time of the particle, acceleration of relative velocity, etc. Developing directions of further investigation on Basset force have also been discussed in the paper.