A New Procedure to Design an Open Circuit Blowing Subsonic Moist-Air Wind Tunnel

Abstract

Featured Application: Moist air wind tunnels are an unknown tool to test, validate theoretical studies, and improve the design of wind turbines under different weather conditions. The present research work shows how a functional subsonic moist-air wind tunnel has been designed. Although this type of wind tunnel has never been developed to date, it is particularly interesting to develop a satisfactory design of feasibility under moist air conditions. Low-speed vertical-axis wind turbines employ different kinds of rotors, such as Savonius, Darrieus, and H-rotor. All these wind turbines present clear advantages, e.g., the horizontal-axis wind turbines are omnidirectional. This means they can work under different wind directions, need lower maintenance, and begin working under low wind speeds of 3 m/s. Recently, a new application of wind concentrators enabled the vertical-axis wind turbines to improve their performance coefficient based on new concepts like moist air phase change, which are being analysed to improve energy conversion. Thus, expectations were raised to design a suitable wind tunnel that accounts for the relative humidity of moist air. An initial prototype showed that the behaviour of open wind tunnels where the relative humidity of moist air was controlled by an adiabatic evaporative process was satisfactory. However, for such wind tunnels, certain improvements like computer control systems would need to be developed.