Computational Study of Combustor–Turbine Interactions

Abstract

The Open National Combustion Code is applied to the simulation of a realistic combustor configuration (Energy Efficient Engine) in order to investigate the unsteady flowfields inside the combustor and around the first-stage stator of a high-pressure turbine. We consider (24 deg) of the full annular Energy Efficient Engine combustor with three different geometries of the combustor exit: one without the vane and two others with the vane set at different relative positions in relation to the fuel nozzle (clocking). Although it is common to take the exit flow profiles obtained by separately simulating the combustor and then feed as the inflow profile when modeling the high-pressure turbine, our studies show that the unsteady flowfields are influenced by the presence of the vane as well as clocking. More importantly, the characteristics (e.g., distribution and strength) of the high-temperature spots (i.e., hot streaks) appearing on the vane are significantly altered. This indicates the importance of simultaneously modeling both the combustor and the high-pressure turbine to understand the mechanics of the unsteady formulation of hot streaks.