| 摘要 |
A wind turbine or propeller comprises a continuous band with an airfoil profile that follows wavy or annular coil (garter spring) shape. When the band rotates about its axis the airfoil presents a largely common angle of attack to the fluid flow. The pressure and suction surfaces of the airfoil swap sides of the band through a generally symmetrical transition across the peaks and troughs of the wave or radial minima and maxima of the spiral. The chord, band path, airfoil section and angle may vary around the path of the band to enhance its ability to entrain more fluid and expel it more judiciously in order to increase its effectiveness as a generator or propeller. The band can be retained about a central hub by spokes, cables or pylons 22or the tops of the waves can be connected to an external ring (figures 4-7). |
