A model for particles deposition in turbulent inclined channels

A computational model for studying the deposition of particles in duct flows in the presence of thermal force under turbulent flow condition was developed. The V2F turbulence model was used to evaluate the mean flow and temperature fields, as well as the root mean-square fluctuation velocities. The V2F model was selected due to its potential for accurate evaluation of the intensity of turbulent velocity fluctuations normal to the wall. The instantaneous velocity field was simulated with the use of the Kraichnan continuous Gaussian random field model and anisotropic turbulence intensities generated by the V2F model. A Lagrangian particle trajectory model was used for evaluating the transport and deposition of particles. The Stokes drag, lift, Brownian, gravity and thermophoretic forces were included in the particle equation of motion. The predicted deposition velocities for vertical and horizontal ducts in the absence of thermophoresis effects were compared with the available experimental data and earlier empirical models, and good agreements were found. A series of simulations for particle deposition on the lower surface of an inclined duct for different imposed temperature gradient fields was performed. The earlier developed models for particle deposition in vertical and horizontal ducts were extended to inclined ducts in the presence of thermophoresis. The simulation results for particle deposition in turbulent inclined duct flows in the presence and absence of thermophoresis were shown to be in good agreement with the empirical model predictions. (C) 2013 Elsevier Ltd. All rights reserved.