Numerical results of the study of the effect of the initial value of the fuel concentration on the parameters of the torch based on parabolized three-dimensional Navier-Stokes equations.

Abstract

This paper presents numerical results of the study of the effect of the fuel concentration in the initial mixture, the turbulence and the initial turbulence value on the parameters of the diffusion gorenje combustible mixture of propane and butane flowing from the nozzle rectangular section.

Three–dimensional systems of Navier-Stokes equations for multicomponent

chemically reacting gas mixtures in physical coordinates are used to model the process under study.

            To calculate the turbulent viscosity, a two-parameter model " κ-ε" is used, with modified empirical parameters. The system of equations is solved by the finite difference method using a modification of the calculation algorithm

and implemented in a SIMPLER type procedure.

It has been numerically revealed that an increase in the initial value of the concentration of a combustible mixture of propane and butane in the range of 0,085 – 0,12 kg/kg does not significantly affect the maximum value of the torch temperature, but leads to an expansion of the thermal displacement zone and to a noticeable elongation and some expansion of the torch.

As a result of numerical research, it was revealed that the growth of the initial fuel concentration value and small satellites  (m_u=0,82 )  significantly affect the length and configuration of the flare, and the initial turbulence values slightly affect the maximum temperature of the flare.

In a flooded flare with a dimensionless initial value of the kinetic energy of turbulence k = 0,05 and the fuel concentration C = 0,12 kg / kg, the length compared to the concentration C = 0,85 kg / kg is 10 calibers longer (relative to the sides of the rectangular nozzle, and heating the fuel to 100 K (with initial temperature 1200 K) leads to an elongation of the torch length by 45% at the initial values fuel concentrations C = 0,085.