Simulation of Free-Falling Solid Body in a Vertical Pipe with Highly Viscous Fluid by Using Moving Particle Semi-implicit (MPS)

Abstract

 This study focuses on the size effect of simulated pipe to the terminal velocity of free-falling solid body in a vertical pipe with highly viscous fluid. The Navier-Stokes equations are employed as governing equations and Moving Particle Semi-implicit (MPS) is chosen as the numerical method. A rigid body model for solid is also applied. The solver of the Pressure Poisson Equation (PPE) is GPU accelerated. The moving speed of “inlet particles” on the bottom is dynamically adjusted according to the solid’s vertical velocity, so that the inlet velocity can represent the solid’s terminal free-falling velocity in cases with normal boundary conditions. Numerical experiments of both 2-D and 3-D are conducted. Various parameters such as density, viscosity and ore’s diameter are also considered. The results show that the inlet velocity increases as the simulated pipe’s width or height gets larger.