Parametric and Correlation Study of Effusion Cooling Applied to Gas Turbine Blades

To pursue higher thermal efficiency in aero gas turbines, the contradiction between extreme high-temperature conditions and material temperature resistance limits has made advanced thermal management technologies crucial. Effusion cooling is a technique that utilizes a large number of small holes (around 0.1 mm in diameter) to cool more effectively. Through numerical simulation, the current research investigates the impact of different parameters on the effectiveness of effusion cooling, including porosities (φ), blowing ratios (Br), height of the porous structure (H), thermal conductivity (λ) of the porous structures, and the ratios of the mainstream temperature to the coolant temperature (Rt). The results show that with the increased porosity, the cooling effectiveness of the porous structure surface first increases and then decreases, while the averaged cooling effectiveness downstream of the mainstream gradually increases. The first two parameters have the greatest influence on the cooling effectiveness. And there is a positive relationship between the blowing ratios and cooling effectiveness, meaning that higher blowing ratios lead to greater cooling effectiveness. A larger height and a smaller thermal conductivity coefficient cause a non-uniform temperature distribution. Different temperature ratios have little influence on coolant coverage pattern. Finally, a correlation is built to predict the cooling effectiveness considering all the parameters which provides fundamental references for the application of effusion cooling.