Experimental investigation of the effects of the Reynolds number on the performance and near wake of a wind turbine
Article dans une revue avec comité de lecture
Author
Date
2023-06Journal
Renewable EnergyAbstract
Wind tunnel experiments provide worthwhile insights for designing efficient micro wind energy harvesters and large-scale wind turbines. As wind tunnel tests with large-scale wind turbines are expensive and not always feasible, most experiments are conducted with geometrically scaled rotors. Furthermore, micro-scale runners used for wind energy harvesting face the issue of lower efficiency than large turbines. A better understanding of Reynolds number effects induced by the downsizing of a turbine would help to design more efficient wind energy harvesters and more faithfully scaled experiments. This paper reports on Reynolds number effects on the performance and wake of micro-scale wind turbines. Wind turbines’ power and torque
coefficients are measured in a wind tunnel for a wide range of Reynolds numbers. The wake axial velocity fields and the vortex core locations are collected for three Reynolds numbers using phase-averaged and phase-locked stereoscopic particle image velocimetry techniques. The results emphasize that an increase in the Reynolds number leads to larger power coefficients, torque coefficients, and optimum tip-speed ratios. Higher Reynolds numbers induce wider wake expansion and a larger axial velocity defect. This quantitative analysis will contribute to a clearer understanding of the scaling effects and help to design more efficient
wind energy harvesters.
Files in this item
Related items
Showing items related by title, author, creator and subject.
-
Article dans une revue avec comité de lectureSmall horizontal axis wind turbines operating at low wind speeds face the issue of low performance compared to large wind turbines. A high amount of torque is required to start producing power at low wind speed to overtake ...
-
Article dans une revue avec comité de lectureThe aim of this paper is to study by CFD the performance and to characterize the velocity fields in the wake of an horizontal axis wind turbine. The design of this wind turbine is far from classical as it has been designed ...
-
Communication avec acteMicro-scale wind turbines are of great interest to supply rechargeable batteries of autonomous sensors in the field of the Internet Of Things (IOT). However, they face the issue of lower dimensionless performance than ...
-
Article dans une revue avec comité de lectureThe advent of the Internet of Things technology has led to a renewed interest in the use of low tip-speed ratio micro-scale wind turbines to supply power to battery-less microsystems. At low tip-speed ratio ( λ), the blade ...
-
Article dans une revue avec comité de lectureIt is well-established that micro-scale wind turbines require high blade solidity in order to overtake friction torque of all mechanical parts and starts operating. Therefore, multi-bladed micro-scale rotors with a low ...