Realistic Velocity And Turbulence Intensity Profiles at the Combustor-Turbine Interaction (CTI) Plane in a Nozzle Guide Vane Test Facility

Authors

I. Cresci - Department of Engineering Science, University of Oxford, UK
P.T. Ireland - Department of Engineering Science, University of Oxford, UK
M. Bacic - Department of Engineering Science, University of Oxford, UK
I. Tibbott - Turbine Systems, Rolls-Royce plc, UK
A. Rawlinson - Turbine Systems, Rolls-Royce plc, UK

Abstract

The continuous demand from the airlines for reduced jet engine fuel consumption results in increasingly challenging high pressure turbine nozzle guide vane (NGV) working conditions. The capability to reproduce realistic boundary conditions in a rig at the combustor-turbine interaction plane is a key feature when testing NGVs in an engine-representative environment. A large scale linear cascade rig to investigate NGV leading edge cooling systems has been designed with particular attention being paid to creating engine representative conditions at the inlet to the NGVs. The combustor simulator replicates the main features of a rich-burn design including large dilution jets and extensive endwall film cooling. CFD simulations have been used to match Reynolds number and mainstream-to-dilution jet momentum flux ratio; velocity and turbulence measurements have been acquired at the NGV inlet plane at ambient temperature. These results show that the velocity and the turbulence intensity distributions are dominated by the endwall cooling flows, and that the measured turbulence length scales reflect the scale of the relevant upstream jets.