Wind Tunnel Tests of a Model Small-Scale Horizontal-Axis Wind Turbine Developed From Blade Element Momentum Theory

Abstract

The small-scale horizontal-axis wind turbines (SHAWTs) have emerged as the promising alternative energy resource for the off-grid electrical power generation. These turbines primarily operate at low Reynolds number, low wind speed, and low tip speed ratio conditions. Under such circumstances, the airfoil selection and blade design of a SHAWT becomes a challenging task. The present work puts forward the necessary steps starting from the aerofoil selection to the blade design and analysis by means of blade element momentum theory (BEMT) for the development of four model rotors composed of E216, SG6043, NACA63415, and NACA0012 airfoils. This analysis shows the superior performance of the model rotor with E216 airfoil in comparison to other three models. However, the subsequent wind tunnel study with the E216 model, a marginal drop in its performance due to mechanical losses has been observed.

Performance assessment of straight and linearly tapered rotors through wind tunnel investigation for off-grid applications

“…From Figure 16, one can specify that for the present SLT rotors C p (M1) > C p (M2) > C p (M3). A systematic twist across the blade section is often required to enhance the performance of straight bladed rotor, such as for the BEMT rotors (Schubel and Crossley, 2012; Siram et al, 2022a). Furthermore, even if the rotor blade is not modelled as per BEMT, a combination of a linear and non-linear twist on the blade is found to be promising (Rahgozar et al, 2020).…”

“…For the present study, the errors in the inflow velocity, HWA signal, RTS output and rpm response is found to be around 1%, 0.5%, 1.2% and 2%, respectively, and the overall uncertainty in the evaluated C p value is found to be about 3.4%. The detail procedure has also been addressed in the reference article (Siram et al, 2022a).…”

Comparative Study on the Effect of Leading Edge Protuberance of Different Shapes on the Aerodynamic Performance of Two Distinct Airfoils

“…The aerodynamic behavior of 12 airfoils (Siram et al 2022) was examined using XFOIL and QBlade tools, and E216 was determined to have the highest lift to drag (L/D) ratio at a low Re, followed by SG6043. Furthermore, considering the maximum L/D ratio, maximum lift coefficient (Cl max), and stall angle (αstall) obtained from XFOIL (Drela and Youngren 2001), E216 had an L/D)max of 68.5, a Cl max of 1.5706, and an αstall of 13.5° at an Re of 10 5 , whereas SG6043 profile had an L/D)max of 66.5, a Cl max of 1.6491, and a αstall of 14.5°.…”