The Effect of Bluff Body Shape on Flame Stability in a Non-Premixed Hydrogen-Methan-Air Mixture Combustion

Abstract

The goal of this study, which focuses on the effect of the bluff-body form on the flame’s stability, is to contribute to the study of the stability of a CH4-H2-Air diffusion flame. It is, in fact, a numerical simulation of a diffusion flame CH4-H2-Air stabilized by a bluff body in three different shapes: cylindrical, semi-spherical and conical. The equations governing turbulent reactive flow are solved using the Ansys CFX program (Navier Stokes equations averaged in sense of Favre). The k-ε model simulates turbulence. For combustion, a mixed EDM/FRC (Finite Rate Combustion) model is utilized. The results of the analysis of temperature profiles, CO2 concentrations, and velocity in axial sections very close to the injector are satisfactory: they meet the criteria of stability, high temperature at a lower speed, and more stable in the case of a cylindrical shape than in the other two cases.