Tandem-Disk 이론을 이용한 수직축 풍력터어빈의 성능 해석

Abstract

An analytical method to predict a variable-geometry vertical-axis wind turbine performance has been developed by applying the combined blade element/momentum theory to the tandem-disk model. In this flow model the flow through turbine was represented by a single streamtube and the blade tip effect was approximated by including both the induced angle of attack and the induced drag at angles below stall limit. Comparison with the available experimental data has shown that the present method predicts turbine output at the corresponding tip-speed ratio much more closely than the conventional theory based on a single-disk model Some of the major performance parameters studied were the effects of blade geometry and Reynolds number. Finally, it has been demonstrated that blade bending moment of a variable-geometry wind turbine is reduced, without loss of a significant power, as the rotational speed increases. The improvement of structural safety at high rotational speed is the big advantage of such a wind turbine over other type of turbines.