Double multiple stream tube theory coupled with dynamic stall and wake correction for aerodynamic investigation of vertical axis wind turbine

Abstract

This study describes an effectively analytic methodology to investigate the aerodynamic performance of H vertical axis wind turbine (H-VAWT). An in-house code based on double multiple stream tube theory (DMST) coupled with dynamic stall and wake correction is implemented to estimate the power coefficient. Design optimization of airfoil shape is conducted to study the influences of the dynamic stall and turbulent wakes. Airfoil shape is universally investigated by using the Class/Shape function transformation method. The airfoil study shows that the upper curve tends to be less convex than the lower curve in order to extract more energy of the wind upstream and generate less drag of the blade downstream. The optimal results show that the power coefficient increases by 6.5% with the new airfoil shape.

Development of a numerical model for floating Vertical Axis Wind Turbines

“…Dynamic stall occurs when the blade rapidly changes the angle of attack and it affects the performances of a VAWT, in which the angle of attack periodically changes, especially at low TSRs. Dynamic stall presents a hysteresis behavior of the flow passing through the blades, whereas the flow does not immediately react to the variation of angle of attack [22]. To address dynamic stall, the model developed by Masse [23] is adopted.…”