Experimental improvements on a tornado-type wind turbine (TTWT) system

Abstract

<p>The Tornado-Type Wind Turbine (TTWT) is a novel design for a wind energy generator utilizing the properties of vortex flow. The TTWT diverts freestream wind into a spiral-shaped chamber, creating a vortex with a low-pressure region in the center. This pressure drop is used to draw ambient air captured below through to the vortex chamber. Energy is extracted with a turbine at this interface. A successful TTWT design will extract more energy at a given wind speed than a traditional horizontal-axis wind turbine (HAWT). The TTWT will be quieter, easier to maintain, and more robust with respect to wind gusts.</p> <p>TTWT models were built and tested in the Wind Simulation and Testing (WiST) Lab at Iowa State. The pressure drop achieved by the basic TTWT design was determined. New modifications to increase the pressure drop were devised and tested. Design modifications were found that improve the performance of the TTWT. Analysis of testing results showed that compared to small HAWTs, cut-in speed is reduced and the TTWT can provide at least three times the power output for low (4 to 10 m/s) wind speeds. Important design elements and flow parameters were identified to direct additional work.</p>