Influence of Reynolds Number and Scale on Performance Evaluation of Lift-type Vertical Axis Wind Turbine by Scale-model Wind Tunnel Tests

Abstract

For Lift-type Vertical Axis Wind Turbine (VAWT), it is difficult to evaluate the performance through the scale-model wind tunnel tests, because of the scale effect relating to Reynolds number. However, it is beneficial to figure out the critical value of Reynolds number or minimum size of the Lift-type VAWT, when designing this type of micro wind turbine. Therefore, in this study, the performance of several scale-models of Lift-type VAWT (Reynolds number : 1.5x10 4 to 4.6x10 4 ) was investigated. As a result, the Reynolds number effect depends on the blade chord rather than the inlet velocity. In addition, there was a transition point of the Reynolds number to change the dominant driving force from Drag to Lift.

Predicting Double-Blade Vertical Axis Wind Turbine Performance by a Quadruple-Multiple Streamtube Model

“…However, small-scale lift-driven VAWTs typically have poor self-starting performance [1]. Therefore, a variety of steps have been tried to improve self-starting performance: increasing blade chord length, adding more blades, using drag-driven wind turbines as a starter, and designing blade airfoils for high aerodynamic performance (for example, [2]). Double-blade vertical axis wind turbines (DB-VAWTs), such as the one shown in Fig.…”

A Study on Relationship among Blade Camber Direction and Pitch Angle and Performance of a Small Straight-Blade Darrieus Wind Turbine by Using Scale Test Model and Gurney Flap

“…So far, we have studied the relationship between the Reynolds number and the performance of the straight-blade Darrieus vertical axis wind turbines (VAWTs), which are expected as medium and small wind turbines with high power output characteristics [1] [2]. In this study, field tests for the practical application of the VAWT and wind tunnel test using small-scale test models of the VAWT were conducted.…”