| 摘要 |
<p>A vertical axis wind turbine (or VAWT) has a rotor (3) which carries vertical aerofoil blades (7) at the outer ends of arms (5). The blades are free to pivot within limits (8) about vertical axes near their leading edges and diametrically opposite blades (7) are linked (9) so that they move substantially in unison, at least at low speeds. In the preferred application, the VAWT is mounted over a sewage treatment tank (1) and is coupled to a co-axial rotor (10) carrying stirring devices which, in use, are immersed in the liquid or slurry. These stirring devices comprise sub-rotors (14, 21) with paddles (16, 17) that sweep just above the base of the tank (1) and just below surface level (L), stirring up sediment and drawing in air bubbles respectively. These sub-rotors counter-rotate with respect to the main stirrer rotor (10), being driven by a coupling (20) to the VAWT, with a further coupling (22) between the sub-rotors and a fixed member (23) drawing the main rotor (10) around.</p> |
