On the calculation of a model of a three-dimensional turbulent diffusion plume

Abstract

In this paper a three-dimensional model of diffusion combustion is presented in the case of the outflow of a combustible gas mixture from a rectangular nozzle and propagating in a heated (with a passing) air flow. For the three-dimensional case, the transformation of the multicomponent concentration equation is described in detail using the conservative Schwab-Zeldovich function with respect to excess concentrations, which reduces the number of diffusion equations to one for a four-component mixture. It is assumed that on the surface of the flame front, the flows of the oxidizer and fuel must satisfy the condition of stoichiometric equality of the consumed and formed substances at the flame front are equal to zero. The three-dimensional system of Navier-Stokes equations is used to describe the flow. To calculate the turbulent viscosity, an algebraic model is used that takes into account the three-dimensionality and temperature inhomogeneity of the jet. A number of numerical results are given as the influence of the initial value of the velocity of the combustible mixture on the flame parameters. During diffusion combustion of a propane-butane mixture. It was found that an increase in fuel velocity does not always lead to an increase in the maximum temperature at the flame front, with other parameters unchanged.