Flow loss control of turbine based on “groove” and “dimple” technology with low Reynolds number

Based on “groove” and “dimple” technology, flow loss control of tubine with low Reynolds number was studied. For “groove” technology, three-dimensional large eddy simulation(LES) method was used to do analysis on control effect of groove position and Reynolds number, while control technology of “dimple” using experimental method. The results show: (1) both of increasing the perturbation amplitude or selecting appropriate disturbance frequency are given significant control effect; (2) two-dimensional span-wise groove processing plays a “disturbance generator” role; (3) three-dimension dimple plays the role of not only “disturbance generator” but also “vortex generator” . The high frequency of the generation and shed of the vortex in the wake of the dimple zone enhances the flow mixture and generates the disturbance that promotes the transition of the separation bubble.