Simulation of Combustion Flowfield in Porous Media with Lattice Boltzmann Method

Abstract

In this paper, two-dimensional numerical modeling of a premixed porous combustion is presented by a Lattice Boltzmann approach. In this solution, the flow distribution is replaced by a pressure distribution equation using the Darcy and Forchheimer model as the multiple-relaxation-time code. The laminar propane-air mixture with Reynolds number of 100 and Prandtl number of 0.75 is put through a silicon carbide porous medium channel. The boundary conditions are included as the uniform inlet temperature and velocity, atmospheric output pressure, periodic wall temperature, and nonslip walls with initial zero gradient for products and reactants. For validation of this model, the presented data of temperature, molar concentration, and velocity comprised published data where the existence of acceptable agreements confirms the accuracy of this solution. The results show that, in the porous medium, the flame position is located at closer distance from the entrance of channel rather than the nonporous medium. Furthermore, the maximum temperature is reduced up to 5.8% when Darcy number is decreasing from 0.1 to 0.001, and with the reduction of Darcy number, the size of vortices is decreased. Moreover, when the porosity coefficient decreases, the size of high-temperature region decreases, and with increasing equivalence ratio from 0.6 to 1, the maximum temperature is significantly augmented with a value of 24.3%.