Heat transfer in a square ribbed channel: evaluation of turbulent heat transfer models

Authors

Beate Woerz - Institute of Jet Propulsion and Turbomachinery RWTH Aachen University
Mark Wieler - Institute of Jet Propulsion and Turbomachinery RWTH Aachen University
Viola Dehe - Institute of Jet Propulsion and Turbomachinery RWTH Aachen University
Peter Jeschke - Institute of Jet Propulsion and Turbomachinery RWTH Aachen University
Michael Rabs - MAN Energy Solutions SE, Oberhausen

Abstract

This paper presents the results of integral heat transfer measurements taken in a square ribbed cooling channel configuration for evaluating heat transfer and turbulent flow characteristics in convective cooled gas turbine blades and draws a comparison with numerical results. The heated section of the channel is either smooth or equipped with 45° crossed ribs on two opposite walls. The first part of the paper describes the instrumentation and experimental setup in detail. The second part compares the numerical calculations with the experimentally determined results. The turbulent heat transfer is calculated using two common algebraic models and three implemented explicit algebraic models, each time in combination with an explicit algebraic Reynolds stress model. The numerical calculations show that the use of higher-order models for the turbulent heat flux provides a higher accuracy of the heat transfer prediction for both configurations. The best model is able to predict almost all results within the experimental uncertainties.