In this paper the combustion of boron dust clouds has been studied numerically in an environment with spatially discrete sources. A thermal model has been generated to estimate the flame propagation speed in various dust concentrations. Furthermore, flame speed as a function of particle diameter has been studied. The results show a very good agreement with the theoretical and experimental data. Also, in this case, a comparison between dust cloud combustion models has been made. Flame front propagation as a function of oxygen mole factor and pressure for certain particle sizes has been studied. (C) 2014 Elsevier B.V. All rights reserved.