Abstract:
There are a great variety of wind turbine constructions but by their principle of operation they are
divided into three main types - sail (Savonius wind power unit), propeller and airfoils (Darrie wind turbine).
At present, propeller-type wind-turbines are the most widely spread. They are produced on a commercial
level in many countries. Other conditions being equal, the power produced by wind power unit (WPU) is
proportional to the area being swept around by a wind wheel. Therefore, Megawatt propeller-type wind
turbines have blades with the length of 40 and more meters. Only aircraft works with a highly-qualified
personnel and corresponding equipment can produce such long blades of a specific shape. Of high interest
have become airfoil wind turbines (Darrie WPU) lately. They are of a simpler construction and have a quite
high wind power utilization factor ( =0.45). In spite of the fact that this is a good index of WPU efficiency,
I have developed a new version of a wind turbine which allows increasing 1.3-1.6 times the value of this
coefficient. This apparatus is named a Bi-Darrie unit. This paper presents the description of a Bi-Darrie
unit, the principle of its operation and the possibility of increasing the wind power utilization factor. Also,
the results of testing an acting laboratory model in an aerodynamic tunnel and a full-length apparatus are
reported.
