Experimental and numerical investigation of the effects of the jet diameter and arrangement of effusion holes on the concave surface of an impingement/effusion cooling system

Impingement/effusion cooling is the most common cooling technique or the leading edge region of a gas turbine blade to increase the maximum allowable turbine inlet temperature and thermal efficiency. This study investigated the flow characteristics of jet impingement onto a concave target plate with effusion holes depending on the shape parameters using experimental and numerical analysis methods. The diameter of the injection plate and the arrangement of the effusion holes were varied at a jet Reynolds number of 5,000. The velocity fields were measured using the PIV technique in nine cases. The CFD results were validated through comparison with experimental results, and the 3D flow structures were estimated by computational fluid dynamics (CFD) simulations. The results are expected to provide knowledge for the design optimization of a cooling system to prevent the thermal load of the leading edge of gas turbine blades. Graphical abstract