CFD Simulation of the Flow Within and Downstream of a High-Swirl Lean Premixed Gas Turbine Combustor

Abstract

CFD analysis of the flow within a high-swirl lean premixed gas turbine combustor and over the 1st row nozzle guide vanes is presented. The focus of the investigation is the fluid dynamics at the combustor/turbine interface and its impact on the turbine. For the configuration in question, temperature indicating paint observations of the nozzle guide vanes, acquired during engine development tests, show features consistent with the presence of a highly rotating vortex core emerging from the combustor. The configuration was modelled by a fully compressible reacting CFD analysis, whose domain stretched from the exit of the combustor swirl generator to downstream of the 1st row nozzle guide vanes. The CFD analysis, when using a Reynolds stress turbulence model, predicted a highly rotating vortex core. The predicted interaction between the core and the nozzle guide vanes were consistent with the temperature indicating paint observations. The interaction is dominated by the vortex core being attracted to the locus of lowest static pressure.