Performance Analysis of the Tornado Wind Energy Concentrator System

The tornado wind energy concentrator system was introduced by J. T Yen (Ref. 1). It consists of a large tower that collects the wind to form a vortex. The low pressure core in the vortex sucks the air through the turbine in the bottom of the tower. In this paper the results of wind tunnel tests on logarithmic spiral shaped towers are presented. Results for models of this type with closed bottom walls have been reported by Windrich et al. (Ref. 2). The present study concentrates on tower models with a bottom opening. The turbine is simulated by a screen. Tower aspect ratio, turbine diameter and turbine load are analysed and optimal values of these parameters are found. Experimental model laws are derived, which are combined with a theoretical flow model, to produce performance predictions as functions of Reynolds number for large scale systems. Preliminary results of this research were reported by Haers and Dick (Ref. 3).