Modares Mechanical Engineering

Modares Mechanical Engineering

Comparison of Dynamic Stall Models Using Numerical and Semi-Empirical Approaches for a Wind-Turbine Airfoil

Authors
sepehr rasekh 1
Saeed Karimian aliabadi 2
mohammad hosseinidoust 3
1 Aerospace Engineering, Faculty of mechanical engineering, Tarbiat Modares University, Tehran, Iran
2 Modares university
3 Tarbiat Modares
Abstract
In this paper, the Semi-Empirical and numerical methods that can be used to investigate the effects of dynamic stall are compared with each other, and the capabilities of the methods are studied. The experimental measurements have been used in order to compare the methods. The Semi-Empirical Leishman-Beddoes (L-B), Snel and ONERA methods have been used, and the finite volume method was being used for numerical simulations. The lift coefficient was being calculated by all the methods at various conditions, and the drag coefficient had been computed by the numerical and Leishman-Beddoes methods. The parameters that have been used in order to compare the methods, are the maximum lift coefficient value, the angle of attack of the largest lift coefficient, the error at upstroke phase and the error at down stroke phase. The results show among the semi-empirical models; the L-B method has the highest precision to predict the lift coefficient, and although the numerical method can investigate the flow with more details, but the error percentage at the down stroke phase is higher than expectations. The results from the drag coefficient modeling show that the numerical method can predict this coefficient better than the L-B method. The results also can help other researchers to select the best dynamic stall model in order to investigate the wind-turbine aerodynamics.
Keywords
Dynamic stall
Wind turbine airfoil
Semi-Empirical models
CFD
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Modares Mechanical Engineering
Volume 18, Issue 3
May 2018
Pages 282-290