Dimensional Analysis of Power Prediction of a Real-ScaleWind Turbine Based on Wind-Tunnel Torque Measurement of Small-Scaled Models

Abstract

A preliminary study of a horizontal-axis wind turbine (HAWT) design is carried out using a wind tunnel to obtain its aerodynamic characteristics. Utilization of data from the study to develop large-scale wind turbines requires further study. This paper aims to discuss the use of wind turbine data obtained the wind-tunnel measurements to estimate the characteristics of wind turbines that have field size. One should measure the torque of two small-scale turbines inside the wind tunnel. The first small-scale turbine has a radius of 0.14 m, and the radius of the second small turbine is 0.19 m. Torque measurement results from both turbines were analyzed using the Buckingham π theorem to obtain a correlation between torsion and diameter variations. The obtained correlation equation was used to estimate the field measurement of turbine power with a radius of 1.2 m. The resulting correlation equation can be applied to approximate the energy generated by the turbine using the size of the field well in the operating area and the tip-speed ratio (λ) of the turbine design.