Free-stream Turbulence Effects on the Boundary Layer of a High-lift Low-Pressure-Turbine Blade  

作　　者：Simoni D. Ubaldi M. Zunino p. Ampellio E. 

机构地区：[1]DIME-Universita di Genova,Via MontaUegro 1,1-16145 Genova,Italy [2]GE AvioAero S.p.A.,V.I Maggio,99 1-10040 Rivalta(TO)-Italy

出　　处：《Journal of Thermal Science》2016年第3期195-206,共12页热科学学报（英文版）

摘　　要：The suction side boundary layer evolution of a high-lift low-pressure turbine cascade has been experimentally in- vestigated at low and high free-stream turbulence intensity conditions. Measurements have been carded out in order to analyze the boundary layer transition and separation processes at a low Reynolds nttmber, under both steady and unsteady inflows. Static pressure distributions along the blade surfaces as well as total pressure distri- butions in a downstream tangential plane have been measured to evaluate the overall aerodynamic efficiency of the blade for the different conditions. Particle. Image Velocimetry has been adopted to analyze the time-mean and time-varying velocity fields. The flow field has been surveyed in two orthogonal planes （a blade-to-blade plane and a wall-parallel one）. These measurements allow the identification of the Kelvin-Helmholtz large scale cohe- rent structures shed as a consequence of the boundary layer laminar separation under steady inflow, as well as the investigation of the three-dimensional effects induced by the intermittent passage of low and high speed streaks. A close inspection of the time-mean velocity profiles as well as of the boundary layer integral parameters helps to characterize the suction side boundary layer state, thus justifying the influence of free-stream turbulence intensity on the blade aerodynamic losses measured under steady and unsteady inflows.

关 键 词：profile losses high-lift profiles free-stream turbulence STREAKS unsteady flows. 

分 类 号：TK14[动力工程及工程热物理—热能工程]