Investigation of microparticle deposition and removal behavior using hybrid thermal Lattice Boltzmann method

Abstract

A numerical method for deposition evolution is proposed by incorporating mechanistic sticking and melt faction sticking model. The hybrid thermal Lattice Boltzmann method is developed to simulate thermal fluid flow, and the particle trajectory is tracked by probabilistic cellular automata model. The proposed model has been validated by experiment and proven to be a promising approach for predicting deposition rate at high–temperature. The contribution of the thermophoresis and Brownian forces to deposition mass is <10% in total. Noteworthily, coarse particles do not necessarily possess higher deposition efficiency. The critical impact velocity (vel = 0.084e–0.48lnStp) and critical shear velocity (vsh,cr = 8.29e–0.46lnStp) are negatively correlated with Stokes number. The average of Nusselt number decreases from 6.94 to 6.17, 5.91, and 5.78 with an increase in eccentricity. The result shows that increasing the tube ellipticity is conducive for reducing deposition at the expense of heat transfer efficiency.