Investigation on Scalar Transport Characteristics of an Inclined Jet-in-Crossflow With Cylindrical Hole Using Large Eddy Simulation

Film cooling is at the heart of gas turbine cooling technologies. The inclined jet-incrossflow is the key physical problem in film cooling. In this paper, the flow field and the scalar transport process in an inclined jet-in-crossflow with cylindrical hole was studied using large eddy simulation. First, recycling and rescaling method was developed to be more robust to generate the inflow wall turbulence. Secondly, a detailed validation on mesh resolution required to resolve wall turbulence was conducted. Thirdly, a new structured mesh generation method using curvedsurface block was developed. By utilizing the methods above, we investigated the time-averaged and temporal vortex structures at a velocity ratio of 0.46. The scalar transport process by the jet-induced vortices were analyzed. We pointed out that the gradient transport hypothesis is limited, and further revealed that the streamwise counter-gradient scalar transport is the main reason of the fully spread of scalar in spanwise direction. © 2022, Science Press. All right reserved.