Hot Streaks and Phantom Cooling in a Turbine Rotor Passage: Part 1—Separate Effects

Abstract

This paper presents experimental documentation and analytical correlations demonstrating the effects of hot streak accumulation and phantom cooling on turbine rotor airfoil surface temperature. Results are shown that quantify the impact of (1) a nonuniform temperature profile at the entrance of a turbine due to combustor-generated hot and cold streaks, and (2) cooling air discharged from the trailing edge of the upstream stator. In Part 1 of this paper, experimental results are shown for a range of controlling variables to identify where streak accumulation and phantom cooling were most likely to be strongest. These variables include streak-to-free-stream density ratio, streak injection location, and coolant-to-free-stream density and velocity ratios. In Part 2 of this paper, experimental results are shown for the combined effects of hot streak and stator coolant. An analytical model is also presented to correlate the experimental results.