Recent Advances in Turbine Heat Transfer—With A View of Transition to Coal-Gas Based Systems

The performance goal of modern gas turbine engines, both land-base and air-breathing engines, can be achieved by increasing the turbine inlet temperature (TIT). The level of TIT in the near future can reach as high as 1700 °C for utility turbines and over 1900 °C for advanced military engines. To ensure the turbine airfoil component integrity operated under such a condition, advanced cooling capacity by both external and internal means was necessary to remove the excessive heat load from the turbine airfoil. This paper discusses state-of-the-art airfoil cooling technologies along with the associated thermal transport issues. Discussion is given based on five key regions on and around an airfoil: leading edge, main body, trailing edge, endwall, and near-tip. Potential implications and challenges of near-term developments in coal-gas based turbines on the cooling technologies are identified. A literature survey focusing primarily on the past 4–5years since the last International Heat Transfer Conference has also been performed.