Affiliation of Author(s):能源与动力学院
Journal:Tuijin Jishu
Abstract:To alleviate the laminar separation on high loaded low pressure turbine cascade of PAKB that operating at low Reynolds number of 2.5×104, a dynamic hump was arranged on the suction surface of the blade for active flow control. The hump, shaped as half sinusoidal, vibrated normal to the blade surface in sine wave, with maximum amplitude of 1 mm and frequency of 200Hz. The effects of hump location and width on cascade performance were studied through unsteady numerical simulation. The cascade with dynamic hump located upstream and close to the peak velocity point has the lowest total pressure loss coefficient, which is reduced by 28.8% compared with uncontrolled cascade. When the hump is placed downstream of separation point or far upstream of peak velocity point, the cascade performance grows worsen. It is also revealed that the effects of hump width on cascade performance are small when putting the hump at the optimum location. The flow control mechanism of laminar separation comes from the continuous small laminar vortices that are detached from the dynamic hump and attached to the suction surface. Continuous vortices confine the low-energy fluid near the suction surface by energy exchange between the free flow and near-wall flow, which suppress the large-scale flow separation. © 2019, Editorial Department of Journal of Propulsion Technology. All right reserved.
ISSN No.:1001-4055
Translation or Not:no
Date of Publication:2019-02-01
Co-author:Xu, Kun,Zhong, Dong-Dong,gn
Correspondence Author:Yang Rongfei