Comparative study of two corrective gradient models in the simulation of multiphase flows using moving particle semi-implicit method

In this study, two corrective gradient models (CGMs) are compared in the simulation of multiphase flows. Linear consistency of the gradient model of moving particle semi-implicit (MPS) method has been recovered by introducing corrective matrix. However, it is found that particles tend to disperse along the streamline while using the CGM proposed in a previous study. Particle shifting (PS) schemes are necessary to reduce the irregularity of particle distribution to stabilize the calculation. To enhance the accuracy and stability, another CGM with dummy particle (CGMD) was proposed in our previous study. This enhanced CGM is featured by linear consistency and purely repulsive pressure gradient force. In this study, this enhanced CGM is modified and applied to multiphase flow simulation. Comparative study suggests that the modified CGM with PS scheme is capable of calculating various multiphase flows and predicting the interface evolution both clearly and accurately.