Flow Mechanism of Cooling Effectiveness Improvement for the Cylindrical Film Cooling Hole with Contoured Craters

2018 5th International Conference on Advanced Materials, Mechanics and Structural Engineering

材料科学;机械制造;土木建筑工程

Bai, Linchao^1^2 ; Zhang, Chao^1^2

Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, Tianjin

300384, China^1

National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin

300384, China^2

关键词: Cooling effectiveness;    Cylindrical holes;    Downstream flow;    Film cooling hole;    Lateral directions;    Mainstream flow;    Reynolds averaged Navier-Stokes equation;    Shear-stress transport;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/473/1/012033/pdf
DOI  :  10.1088/1757-899X/473/1/012033

来源: IOP

【 摘 要 】

In this paper, a typical cylindrical hole with contoured craters is investigated in terms of the downstream flow field by numerical method at blowing ratios of 0.5, 1 and 1.5. The flow field and the cooling effectiveness are analyzed using three-dimensional Reynoldsaveraged Navier-Stokes equations with the shear stress transport turbulence model. In comparison to the cylindrical hole, the cratered hole shows a wider coolant coverage in lateral direction and a lower penetration into the mainstream flow due to the larger hole exit area. Moreover, the interaction between the coolant and the curved protrusion induces a new antikidney- shaped vortex pair, which can obviously improve the cooling coverage and thus the cooling effectiveness. The area-averaged cooling effectiveness for the cratered hole is always higher than that for the cylindrical hole at all three blowing ratios.