Open AccessInfluences of trailing edge split flap on the aerodynamic performance of vertical axis wind turbine
Author(s) -
Zhang Lijun,
Gu Jiawei,
Hu Kuoliang,
Zhu Huaibao,
Miao Junjie,
Li Xiang,
Ma Dongchen,
Mi Yuxia,
Wang Zhiwei
Publication year - 2021
Publication title -
energy science and engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.638
H-Index - 29
ISSN - 2050-0505
DOI - 10.1002/ese3.818
Subject(s) - airfoil , trailing edge , turbine , aerodynamics , deflection (physics) , leading edge , reynolds number , mechanics , geology , marine engineering , structural engineering , geometry , mathematics , physics , engineering , aerospace engineering , optics , turbulence
To improve the performance of a 3.5 kW small H‐type vertical axis wind turbine (VAWT) with the airfoil of NACA0015, a design method for installing split flaps at the trailing edge of a blade is proposed. By solving the two‐dimensional URANS equations, the simulation of VAWTs is carried out. The influences of the length (10% c ‐30% c ), arrangement positions (90% c ‐70% c ), and deflection angles (10°‐30°) of the split flaps on the performance of VAWT are determined by orthogonal design when Reynolds number is 2 × 10 5 and 1 < TSR < 3. In accordance with the influence degrees of these parameters and adopting the maximum wind energy utilization ratio C P max and the maximum efficient operating range Δ λ max as research objectives, the optimum flap length is determined as 22% c , the optimum deflection angle is 10°, and the optimum arrangement position is 92% c . Further studies show that the C P max is increased by 5.8% and its Δ λ max is increased by 25.9% after installing split flaps. Meanwhile, split flaps can change the Kutta‐Joukowsky trailing edge boundary condition, which increases the flow circulation around the airfoil. Also, split flaps can increase the positive pressure difference in the upwind area and reduce the negative pressure difference in the downwind area, which significantly improves the aerodynamic performance of VAWTs.