High-solidity straight-bladed vertical axis wind turbine: Numerical simulation and validation

This study uses 2.5D large eddy simulations (LES) and wind tunnel experiments to investigate aerodynamics of high-solidity straight-bladed vertical axis wind turbines (SBVAWTs). The experimental setup and numerical simulation strategy of a high-solidity SBVAWT are first introduced. The self-start performance of the high-solidity SBVAWT is then assessed. The aerodynamic forces acting on the rotating high-solidity SBVAWT are computed by 2.5D LES method, and the numerical results are compared to those from the wind tunnel experiments. The numerical and experimental results indicate that the high-solidity SBVAWT has a good self-start capability. The results also indicate that 2.5D LES method can provide satisfactory prediction to the aerodynamic forces, especially for the straight blade in the upwind zone. Flow characteristics of the high-solidity SBVAWT with different tip speed ratios (TSRs) are finally analyzed, and the mechanism of variation of aerodynamic forces in one rotational circle is revealed. By comparing the flow characteristics of the high-solidity SBVAWT with the moderate-solidity SBVAWT, it is observed that high solidity introduces complex flow field and the aerodynamic force curves of the high-solidity SBVAWT are different from those of the moderate-solidity SBVAWT.