Numerical investigation of alleviation of undesirable effect of inter-blade vortex with air admission for a low-head Francis turbine

作     者：Long-gang Sun Peng-cheng Guo Luo-chang Wu Long-gang Sun;Peng-cheng Guo;Luo-chang Wu

作者机构：State Key Laboratory of Eco-hydraulics in Northwest Arid RegionXi’an University of TechnologyXi’an710048China 

出 版 物：《Journal of Hydrodynamics》 (水动力学研究与进展B辑（英文版）)

年 卷 期：2020年第32卷第6期

页      面：1151-1164页

核心收录：

学科分类：080704[工学-流体机械及工程] 080103[工学-流体力学] 08[工学] 0807[工学-动力工程及工程热物理] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.51839010) 

主　　题：Numerical simulation inter-blade vortex air admission energy dissipation pressure fluctuation Francis turbine 

摘      要：In order to compensate for the stochastic nature of the power grid due to the tremendous development and the integration of renewable energy resources and meet its other requirements,the hydraulic turbines are forced to operate more frequently under partial load conditions with singular and misaligned flows inevitably excited by the inter-blade *** paper presents numerical investigations of the unsteady characteristics of the inter-blade vortex for a low-head model Francis *** SST k-ωturbulent model is used to close the unsteady Reynolds-averaged Navier-Stokes(RANS)*** flow structure of the inter blade vortex predicted by the numerical simulation is confirmed by experimental *** is shown that the total vortex volume in the runner sees a quasi-periodical oscillation,with significant flow separations created on the suction side of the runner blade.A counter measure by using the air admission into the water from the head cover is implemented to alleviate the undesirable effect of the inter-blade *** analyses show that the development of the inter-blade vortex is significantly mitigated by the injecting air that controls and changes the spatial distribution of ***,the flow aeration with a suitable air flow rate can reduce the energy dissipation caused by the inter-blade vortex and plays a critical role in preventing the excessive amplitudes of the pressure fluctuation on the suction side of the runner *** investigation provides an insight into the flow mechanism underlying the inter-blade vortex and offers a reference to alleviate and mitigate the adverse consequences of the inter-blade vortex for the Francis turbine.