Large-eddy Simulation of Non-premixed Flames, Using a Novel Pressure-correction Approach

An efficient time accurate algorithm with great potential in LES simulations of non-premixed flames is presented for numerical simulations of low-Mach number variable density flows. The algorithm is based on a segregated solution formalism in the class of pressure-correction methods. It shows good conservation properties and returns stable results, regardless of the difference in density between neighboring cells. In the illustrative example, a flamesheet model is used to describe the combustion of fuel and oxidizer. The convergence rate of the method is discussed for a 1D channel flow, containing both fuel and oxidizer. Furthermore, results for a computationally more demanding 2D testcase of a reacting mixing layer are discussed. Eventually, it is shown that the method can be applied to a real-life situation, of a turbulent non premixed swirling methane-air jet-flame.