Numerical Study on Liquid Fuel Spray Behavior in Turbulent Flames Using LES

Abstract

In the present study, Large-Eddy Simulation (LES) modeling for turbulent spray combustion flows has been developed in conjunction with the Eulerian/Lagrangian method for the gas phase and dispersed phase representation and flamelet approach for combustion modeling. Moreover, a new thermal energy coupling model is proposed to estimate the thermal interaction between the gas phase and the dispersed phase. The governing equations for the gas phase are the mass and momentum conservation equations and the mixture fraction transport equation. The governing equations for spray droplets are the mass, momentum, and thermal energy equations for each droplet. We applied the numerical procedure to a laboratory-sized spray combustor and found that procedure can predict key features of turbulent spray combustion phenomena, such as the temperature distribution of the combustion gas, individual droplet behavior, and droplet vaporization phenomena. Moreover, the flame temperature drop caused by the thermal impact from the spray droplets is expressed properly by employing the coupling model.