FILM-COOLED GAS TURBINE VANE TEMPERATURE CALCULATIONS WITH AN ITERATIVE CONJUGATE HEAT TRANSFER APPROACH USING EMPIRICAL FILM CORRELATIONS

Open Access
Author:
Jennings, Timothy John
Graduate Program:
Mechanical Engineering
Degree:
Master of Engineering
Document Type:
Master Thesis
Date of Defense:
April 28, 2011
Committee Members:
  • Savas Yavuzkurt, Thesis Advisor
Keywords:
  • conjugate
  • gas turbine
  • film-cooling
  • heat transfer
Abstract:
The design of gas turbine blades and vanes is a challenging task. The nature of the problem calls for high speed, high temperature, turbulent flows to be predicted accurately. The conventional technique for solving such flows neglects conduction through the blade material and relies on turbulence models to predict the film-cooled flow. This results in errors as large as 14% when predicting the wall temperature for internally cooled turbine blades. A loosely coupled conjugate heat transfer method called Iterative Conjugate Heat Transfer (ICHT) was developed to incorporate conjugate effects. A Reduced-Order Film Model (ROFM) was also developed to use experimental data or empirical correlations in place of turbulence models for solving film-cooled flow. ROFM automates the process of setting up and solving CFD solutions. The development and a demonstration of this technique is presented. A CFD solution of a film-cooled C3X blade was obtained to determine the influence of conjugate effects and the accuracy of ROFM. Results show a maximum deviation for wall temperatures of 3.33%, which was roughly 2.5% of the initial total gas temperature, and equivalent to 18 °C, showing good agreement with experimental results. The change in wall temperature due to conjugate effects was a maximum of 40 °C, which is considered very significant in gas turbine design.