Accurate continuum surface force model applicable to particle methods
SUN Chen, JIANG Shengyao, DUAN Riqiang
Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
Abstract：The continuum surface force (CSF) model was used to improve the accuracy of surface tension calculation using the particle method. A geometric method was developed to accurately detect the boundary particle with the curvature calculated from the surface divergence of the unit normal, which only depends on the boundary particles in the interaction domain. The surface tension was then calculated only on the boundary particle. Curvature calculation results using a circle and an ellipse showed that the curvature calculation is more accurate with the proper resolution and smoothing length. Two-dimensional, two single-phase models of square drop oscillations and two drops colliding with surface tension effects were simulated using the moving particle semi-implicit (MPS) method. The predicted oscillation periods agreed well with analytical results with reasonable shape and smooth surfaces. The results indicate that this improved CSF model can accurately simulate the surface tension effect in two-phase flows.
孙晨, 姜胜耀, 段日强. 适用于粒子法的精准连续表面力模型[J]. 清华大学学报（自然科学版）, 2018, 58(2): 181-187.
SUN Chen, JIANG Shengyao, DUAN Riqiang. Accurate continuum surface force model applicable to particle methods. Journal of Tsinghua University(Science and Technology), 2018, 58(2): 181-187.
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2018, Vol. 58 
