Large Eddy Simulation of Axi-Symmetric Dump Combustor with and without Swirl in Curvilinear Coordinates

Abstract

Large Eddy simulations (LES) approach in generalized curvilinear non‐orthogonal coordinates is studied using a conventional approach, where filtering is performed prior to the transformation. This LES methodology based on the conventional approach is used to perform the LES of an axi‐symmetric dump combustor (ACDC) at Reynolds numbers of 10,000 and 11,700 with and without swirl, respectively. Vortex formation, which affects the combustion characteristics, is studied for the ACDC with and without swirl. LES results are compared with experiments, and the predictions are in satisfactory agreement. The reattachment length decreases for swirling flows. Effects of choosing a coarse grid resolution and conventional inflow/outflow boundary condition are also studied. LES captures the recirculation zone and central toroidal recirculation zone reasonably well. The present study showed that the conventional approach was more appropriate while implementing the LES module in existing curvilinear RANS code.