Vertical axis wind turbine (VAWT) is one of the main equipment for wind energy conversion, and computational fluid dynamics (CFD) is the most effective method to study its aerodynamic behavior. Rotor solidity, which is defined by three physical parameters, blade number, chord length and rotor radius, has been identified as a key parameter on the performance of a VAWT. However, there is a lack of systematic studies on these three parameters in the literature. To examine the effect of the solidity, two-dimensional numerical simulations were performed based on the shear stress transport-delayed detached eddy simulation (SST-DDES) method. The SST-DDES model was validated against published experiment data by comparing the power coefficient (CP) and drag coefficient (CD). Besides, domain size, mesh density and time step were analyzed and optimized in order to reduce the computational time cost and to improve the reliability of the simulations. Cases of different solidities were computed and curves of CP were obtained. There exists a maximum CP when the solidity value varies between 0.2 and 0.5. VAWTs with two blades achieve a higher peak of CP and a wider range of effective tip speed ratio. Increasing the radius of the rotor can significantly increase the peak CP of VAWTs. By keeping the solidity and rotor radius constant, VAWTs with different blade numbers have similar CP curves.
CHEN Yu-ming
,
FU Sau-chung
,
ZHANG Jun-sheng
,
OU Bao-xing
,
WU Chi-li
,
CHAO Yu-hang
. Effect of Solidity on the Performance of a Vertical Axis Wind Turbine by Numerical Simulation Analysis[J]. Advances in New and Renewable Energy, 2017
, 5(6)
: 409
-416
.
DOI: 10.3969/j.issn.2095-560X.2017.06.001
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