Repository logo
 

An experimental and computational study of tip clearance effects on a transonic turbine stage


Change log

Authors

Jackson, AJ 
Wheeler, APS 
Ainsworth, RW 

Abstract

This paper describes an experimental and computational investigation into the influence of tip clearance on the blade tip heat load of a high-pressure (HP) turbine stage. Experiments were performed in the Oxford Rotor facility which is a 1½ stage, shroudless, transonic, high pressure turbine. The experiments were conducted at an engine representative Mach number and Reynolds number. Rotating frame instrumentation was used to capture both aerodynamic and heat flux data within the rotor blade row. Two rotor blade tip clearances were tested (1.5% and 1.0% of blade span). The experiments were compared with computational fluid dynamics (CFD) predictions made using a steady Reynolds-averaged Navier–Stokes (RANS) solver. The experiments and computational predictions were in good agreement. The blade tip heat transfer was observed to increase with reduced tip gap in both the CFD and the experiment. The augmentation of tip heat load at smaller clearances was found to be due to the ingestion of high relative total temperature fluid near the casing, generated through casing shear.

Description

Keywords

Tip leakage flow, Heat transfer, Transonic turbine

Journal Title

International Journal of Heat and Fluid Flow

Conference Name

Journal ISSN

0142-727X
1879-2278

Volume Title

56

Publisher

Elsevier BV
Sponsorship
This work was sponsored by Rolls-Royce plc and the Isle of Man Government.