Experimental Study of Three Different Airfoils Applied to Diffuser-Augmented Wind Turbines

Abstract

Over the years the electricity generation based on alternative energy systems applied to remote regions has been increased in Brazil, mainly due to the lack of conventional electric grid structure, specially in places as the Amazon. In this scenario, it is wellknown that the wind power technology attracts great attention because the wind potential available in the country coast is really representative, leading this sort of technology to an important position into the local energy matrix. However, it is necessary to search new technology developments in order to get efficient turbines applied to isolated regions, where usually low wind speeds are found. The small wind systems using diffuser appear as a relevant alternative, which can be adapted to the characteristics of low wind speed conditions. Hence, in this work, an experimental study on diffusers using three different airfoils (SELIG 1223, EPPLER 423 and NACA 4412) was performed. The goal was to evaluate the influence of the diffuser velocity ratio on the classical theory (axial moment theory with diffuser), in order to show the increasing efficiency typically noticed in studies on Diffuser-Augmented Wind Turbines (DAWTs). In this regard, it was concluded that the wind speed increases under diffuser effect even whether the geometric model is composed by two straight parallel airfoils. Consequently, a DAWT might be adapted to low wind speeds usually found in northern Brazil.

Vehículos aéreos no tripulados como alternativa de solución a los retos de innovación en diferentes campos de aplicación: una revisión de la literatura

“…Si bien el origen de estas tecnologías fue militar, en la última década sus aplicaciones se han extendido a la agricultura, el medio ambiente, geociencia y logística, por mencionar algunas [3,4,5]. Estos campos permiten demostrar la versatilidad de estas aeronaves, originando investigación y creación de empresas dedicadas al desarrollo de sistemas y servicios basados en su uso [6]. La mejora continua de estos vehículos está basada actualmente en técnicas de inteligencia artificial (en inglés, Artificial Intelligence -AI) con la finalidad de optimizar las rutas de vuelo mediante generación de nuevos patrones, evasión de obstáculos para prevenir colisiones y reducción del consumo energético para un mayor tiempo de vuelo.…”