Resuspension of small particles from multilayer deposits in turbulent boundary layers

Abstract This paper describes a hybrid kinetic model for the resuspension of micron-size particles from multilayer deposits in a fully developed turbulent boundary layer. The rate of removal of particles from any given layer depends upon the rate of removal of particles from the layer above which acts as a source of uncovering and exposure of particles to the resuspending flow. The primary resuspension rate constant for an individual particle within a layer is based on the Rock'n'Roll (R'n'R) model using non-Gaussian statistics for the aerodynamic removal forces acting on the particles ( Zhang et al., 2013 ). The coupled layer equations that describe multilayer resuspension of all the particles in each layer are based on the generic lattice model of Friess & Yadigaroglu (2001) which is extended here to include the influence of layer coverage and particle size distribution. The model is used to investigate a range of effects, including the influence of layer thickness on resuspension, the spread of inter-particle adhesive forces within layers, Gaussian and non-Gaussian pdfs for the removal forces and the associated timescales. Finally model predictions are compared with data from two resuspension experiments – STORM ( Castelo et al., 1999 ) and BISE ( Alloul-Marmor, 2002 ).