Investigations of heat transfer and pressure loss in an engine-similar two-pass internal blade cooling configuration

Authors

C. Waidmann, R. Poser, J. von Wolfersdorf - University of Stuttgart
M. Fois, K. Semmler - MTU Aero Engines GmbH, Munich, Germany

Abstract

In this study, the pressure loss and heat transfer characteristics of a two-pass internal cooling channel with engine-similar cross-sections were investigated experimentally. The channel consists of a rib-turbulated trapezoidal leading edge pass, a sharp 180° bend, and a ribbed rectangular outlet pass as typical for a low-pressure turbine blade forward cooling scheme. Heat transfer measurements have been performed to obtain local cooling information on pressure side and suction side surfaces. The transient TLC (Thermochromic Liquid Crystal) technique has been applied, CFD simulations are used to address the effects of test-specific inlet geometries on the flow and temperature fields in the test channel. A technique to calculate fluid bulk temperatures from the thermocouple measurements using the temperature field information of the CFD simulation has been applied.