Paper Title
Computational Fluid Flow Analysis and Performance Evaluation of a Shrouded Wind Turbine with Wind Lens Technology

Abstract
The paper aims to present the new technological innovation for the efficient energy production through the wind turbine. At wind energy section of Kyushu University, a new efficient wind power turbine has been developed. The system has been attached to a diffuser shroud named “Wind Lens” [1]. The Wind lens concentrates the wind energy through the turbine by which the output power of the wind turbine will be increased dramatically. The power output of the wind turbine with wind lens technology is 2.5 to 5 times of the convectional wind turbine. This paper focus on the complete research and flow analysis of the wind lens turbine and comparison of the output power levels at different wind velocities. Since wind load on the Wind-Lens turbine is larger than typical wind turbine, application of the Wind Lens to turbine in larger size faces structural challenge. The behavior of the air flow around the wind lens turbine in stream lines produced by the cardice smoke generator (CSG) in the wind tunnel is observed and evaluated for the better formation of the eddy’s, creating a low-pressure region behind the turbine for better power generation. The output performance of the wind turbine with C-type compact brimmed diffuser with different length is observed and performance curves are generated with the power coefficient (Cp). The power output is expected to be 2-3 time large from the convectional wind turbine, when the ratio between the length and height of the brim is greater than 0.1 (Lt/h>0.1). On contrast the wind lens turbine generates much more power than the conventional turbine and produce very less noise. The Power output of the wind lens turbine is directly proportional to the wind speed cubed (P α V3). The 1.4 times increase in the wind speed leads to 3 times increase in the power output. The paper focuses on the comparative study of the wind lens turbine with the theoretical data from the computational fluid flow analysis on the simulation software and the actual data obtained from the wind tunnel analysis monitoring the air stream flow and behavior of the air stream in contact with the wind lens turbine. Keywords - Wind Lens, Kyushu University, Cardice Smoke Generator (CSG), Brimmed Diffuser