Wall-Modelled Large Eddy Simulations of Axial Turbine Rim Sealing

Abstract

This paper presents WMLES simulations of a chute type turbine rim seal. Configurations with an axisymmetric annulus flow and with nozzle guide vanes fitted (but without rotor blades) are considered. The passive scalar concentration solution and WMLES are validated against available data in the literature for uniform convection and a rotor-stator cavity flow. The WMLES approach is shown to be effective, giving significant improvements over an eddy viscosity turbulence model, in prediction of rim seal effectiveness compared to research rig measurements. WMLES requires considerably less computational time than wall-resolved LES, and has the potential for extension to engine conditions. All WMLES solutions show rotating inertial waves in the chute seal. Good agreement between WMLES and measurements for sealing effectiveness in the configuration without vanes is found. For cases with vanes fitted the WMLES simulation shows less ingestion than the measurements, and possible reasons are discussed.

A Coupling Framework for Multi-Domain Modelling and Multi-Physics Simulations

“…It was found that flow solutions based on RANS are unable to predict the correct amount of hot gas ingress and, as a result, the metal temperature within the cavity was strongly underpredicted. Ingress prediction is a complex, longstanding problem related to turbulence modelling [ 33 , 34 , 35 ] and is not the object of the current analysis. In this paper, inlet and outlet boundary conditions are applied at the rim seals of each stator well to guarantee the values of hot gas ingestion consistent with those prescribed in the benchmark SC03 model.…”