An Investigation on Performance of Shrouding a Small Wind Turbine with a Simple Ring in a Wind Tunnel

Document Type: Research Article


1 Department of Agriculture, Tarbiat Modares University, Tehran, Iran.

2 Department of Agriculture, Tarbiat Modares University, Tehran, Iran

3 Department of Agricultural, Shahrood University OF Technology, Shahrood, Iran


Ducted wind turbines are a kind of small wind turbine having a diffuser or any other shape around the rotor which increases the air flow through the blades and absorbs more power. In the present study, a small wind turbine was ducted with a relatively simple ring and its performance was investigated in a wind tunnel. The duct is shaped using rolling steel sheets on a sloping surface and finally fabricated in double-glazed surfaces. The turbine utilizes polyester resin glass fiber-armed composite hollow blades. Bare turbine produces 165 watts in its highest power generation mode which can reach 282 watts when it is ducted. The evaluation of the system in the wind tunnel showed that the power generation of the ducted system compared to a conventional turbine was 14 % higher on average. Furthermore, the rotor speed of the ducted turbine was 45 % higher than the bare one which increases the tip speed ratio (TSR). In this study, TSR increment raised the absorbed power in the developed wind turbine.


Main Subjects

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