| 摘要 |
<p>The invention relates to a method and a blade for enhancing the performances of windmills employed in an electric power generating wind plant, with a view to improving the efficiency of exploitation of potential wind energy. According to the invention, the method consists in taking air from the overpressure region of the front side of a blade profile (p) and directing the said air flow to the negative pressure region on the back side of the profile (p) through a slot (f) which, at values of the incidence angle (α) exceeding 8...10°, opens into a leading edge (b) of the profile (p), the pressurized air passed through the slot (f) compensating the negative pressure on the back side of the profile (p) and determining the displacement of the boundary layer separation point as close as possible to the rear edge of the profile (p). The claimed blade comprises a front edge slat (1) of the blade profile (p) which, at small values of the incidence angle (α) is maintained in a closed position, perfectly matching the outline surface of the blade profile (p), while, at values of the incidence angle (α) exceeding 8...10°, the slat (1) breaks the continuity of the profile (p) by moving forwards and downwards, to an open position in which a slot (f) is formed, the slat (1) moving freely, under the effect of the pressure difference between the front side of the profile (p) and the back side thereof, or being moved automatically by means of a computer (15) which collects data provided by a sensor (16) for monitoring the wind velocity, a sensor (17) for monitoring the incidence angle (α) and an apparatus (18) for measuring the general pitch of the windmill, and calculates, depending on said data, the required size of the slot (f), finally controlling the motion of the slat (1) by means of an actuator (14).</p> |
