A new design concept is introduced to control the near-wall integration between the hot-gas boundary layer and the cooling jets in order to enhance the adiabatic film cooling effectiveness of the gas turbine blades. In this new approach, another film cooling port, having a very low blowing ratio, which prevents formation of the counter-rotating vortex pare, is applied just upstream of the main ...

Aero gas turbine engines have been using mainly film cooling and convection cooling techniques. For operating at high gas temperature amongst different cooling options the transpiration cooling technique has emerged as the most promising technique to improve the gas turbine cycle performance by allowing higher turbine inlet temperatures. This paper investigates the advantages of transpiration c...

Air film cooling has been widely employed to cool gas turbine hot components such as combustor liners, combustor transition pieces, turbine vanes and blades. Enhancing air film cooling by injecting mist with tiny water droplets with diameters of 5-10μm has been studied in the past on flat surfaces. This paper focuses on computationally investigating the curvature effect on mist/air film cooling...

A new measurement technique for the determination of the heat transfer coefficient and the film cooling effectiveness is presented. It is based on a regression of multiple transient liquid crystals experiments using an electrical heater-foil producing a nonhomogeneous surface heat flux. This is particularly interesting for film-cooled surfaces where each cooling hole in the heater-foil leads to...

Large-eddy simulations are performed to analyze film cooling in supersonic combustion ramjets (Scramjets). The transonic film cooling flow is injected through a slot parallel to a Ma = 2.44 main stream with a fully turbulent boundary layer. The injection Mach number is Mai = 1.2 and adiabatic wall conditions are imposed. The cooling effectiveness is investigated for adverse and favorable pressu...

An experimental study of hydrodynamics of film cooling is performed by using a single longitudinal slot on a cylindrical model simulated to the leading edge of the gas turbine blade. The model is set up into the test section of an open-circuit induced flow wind tunnel which provides the main flow. The injected air, as a secondary film flow, produced from a high pressure compressor is considered...

Film cooling is a cooling technique widely used in highperformance gas turbines to protect the turbine airfoils from being damaged by hot flue gases. Motivated by the need to further improve film cooling in terms of both cooling effectiveness and coolant coverage area, the mist/air film cooling scheme is investigated through experiments in this study. A small amount of tiny water droplets (7% w...