A finite particle method with particle shifting technique for modeling particulate flows with thermal convection

Abstract

Particulate flows with thermal convection are very challenging to simulate numerically due to the existence of constantly moving boundaries and complex heat-fluid coupling effects. Meshfree and particle methods have special advantages in modeling complex fluid flows with moving boundaries. However, previous works based on meshfree modeling mainly focused on either particulate flows only with momentum exchange or natural thermal convection. In this paper, a finite particle method integrated with particle shifting technique (FPM-PST) is developed for modeling particulate flows with thermal convection. FPM is an improved smoothed particle hydrodynamics (SPH) method with better accuracy while extremely irregular particle distribution may lead to ill-conditioned corrective matrix and terminate the simulation. PST can achieve regular particle distribution through shifting highly disordered particles while current PST is based on conventional SPH of poor accuracy. A number of numerical examples demonstrated that FPM-PST is a novel approach for modeling thermal particulate flows with good performance in accuracy and stability. It has better accuracy than the conventional SPH and can obtain comparable results with those from other sources. The unphysical voids can also be avoided by FPM-PST. From the FPM-PST simulations, it is observed that at relatively low Reynolds numbers thermal convection between hotter or colder particles and the fluid causes significant increase or decrease in the drag force acting on particles, while the thermal convection has little influence on the particle motion at relatively high Reynolds numbers.