Design and Testing of a LUT Airfoil for Straight-Bladed Vertical Axis Wind Turbines

Abstract

The airfoil plays an important role in improving the performance of wind turbines. However, there is less research dedicated to the airfoils for Vertical Axis Wind Turbines (VAWTs) compared to the research on Horizontal Axis Wind Turbines (HAWTs). With the objective of maximizing the aerodynamic performance of the airfoil by optimizing its geometrical parameters and by considering the law of motion of VAWTs, a new airfoil, designated the LUT airfoil (Lanzhou University of Technology), was designed for lift-driven VAWTs by employing the sequential quadratic programming optimization method. Afterwards, the pressure on the surface of the airfoil and the flow velocity were measured in steady conditions by employing wind tunnel experiments and particle image velocimetry technology. Then, the distribution of the pressure coefficient and aerodynamic loads were analyzed for the LUT airfoil under free transition. The results show that the LUT airfoil has a moderate thickness (20.77%) and moderate camber (1.11%). Moreover, compared to the airfoils commonly used for VAWTs, the LUT airfoil, with a wide drag bucket and gentle stall performance, achieves a higher maximum lift coefficient and lift–drag ratios at the Reynolds numbers 3 × 105 and 5 × 105.

An improved LB method for predicting dynamic characteristics of Vertical Axis Wind Turbine airfoils

“…The four typical airfoils for VAWT are employed to study on dynamic characteristics of VAWT by using the improved LB model, they are NACA0018, S1046, DU06-W-200 (AACU, 2021), and LUT airfoil (Li et al, 2018), respectively. Among them, NACA0018 and S1046 are symmetric airfoils and are commonly used to VAWT, while DU06-W-200 and LUT airfoil are dedicated asymmetrical airfoils for VAWT.…”

Optimization of the hydrodynamic performance of a vertical Axis tidal (VAT) turbine using CFD-Taguchi approach

“…Since the efficiency of a VAT turbine is quite sensitive to the particular shape used for the hydrofoil [71], a qualitative assessment for the pressure coefficient for the baseline (symmetric) and cambered hydrofoils is performed to obtain a deeper understanding of this impact. The pressure coefficient over a hydrofoil can be determined by the pressure and stream properties as follows [72]: 14) where Qp: the pressure coefficient; P: the pressure; Pi: the freestream pressure.…”

Special Issue on Wind Turbine Aerodynamics

“…There are 2 papers dealing with the development of vertical axis wind turbines. Li et al [19] designed a Lanzhou University of Technology (LUT) airfoil for straight-bladed vertical axis wind turbines with an objective of maximizing its aerodynamic performance. Zhao et al [20] introduced a variable pitch approach for improving the performance of straight-bladed vertical axis wind turbine at rated tip-speed-ratio, and it was found that the new variable pitch approach can achieve an 18.9% growth of the peak power coefficient of the vertical axis wind turbine at the optimum tip-speed-ratio.…”