Diffuser Augmented Wind Turbine: A Review Study

Abstract

Wind energy is seeing rapid growth and development in many nations, particularly in metropolitan areas. As is generally known, standard commercial wind turbines are intended to operate at high wind speeds. In areas where wind speeds are low, such as urban areas, commercial turbines work at low efficiency. Therefore, it has become necessary to introduce new wind energy technologies to improve the efficiency of turbines, taking into account the cost reduction. Enclosing wind turbines inside a diffuser is believed to be an innovative way to harvest wind energy. This is due to the pressure drop at the outlet of the diffuser, which leads to an increase in the flow rate at the diffuser inlet and hence improved Wind turbine efficiency. This technology allows to use the concept of diffuser Augmented Wind Turbines (DAWT) in locations with low wind speeds. The current review presents several diffuser engineering configurations that have been submitted by many researchers, some of which were studied in simulations while others were studied in experiments as well as theoretical studies. The main aims of this study were to provide short notes on DAWT concepts. Moreover, the summary obtained indicated that the new design of the small flanged diffuser, within the ideal geometric parameters, is able to significantly increase the turbine efficiency.