Oscillating blades wind turbine

The APWonders Srl will bring to market a vertical rotation axis turbine whose performances are better than those of current drag-based vertical axis wind turbines. Thanks to its construction scheme of new conception, the novel vertical axis turbine addresses the problem of maximizing the efficiency of wind turbines with a vertical axis.
The pairs of blades are oriented automatically, no electric motors involved, in the open position so as to oppose the maximum surface to the wind when they move in the wind direction and are arranged in the closed position when they move in the opposite direction to the wind minimizing the resistant surface of the blades. If we take into consideration the drag coefficients of the blades, available in literature, it is simple to verify the improved performance of the novel wind turbine. A common drag-based Savonius turbine has two blades made by half cylinders at 180 degrees, the torque is generated by the difference in the drag coefficients of the blade moving upwind, which is 1.2, and the drag coefficients of the blade moving downwind, which is 2.3. The electrical power produced is a direct function of the difference between the two drag coefficients, in this case 2.3-2.1=1.1. For the novel oscillating blades turbine from APWonders Srl the difference between the two drag coefficients of the blade moving downwind and blade moving upwind is 1.98-0.1=1.88. From this calculation it is evident the potential improvement in efficiency of the new invention.
The advantages of the innovative oscillating blades wind turbine can be summarized in the following points: it works with wind coming from any direction, high annual energy production, low cost, ultra-quiet operation even with strong winds, the formation of ice on the blades does not compromise its performance, it does not constitute a source of danger to birds, in the case of medium to large turbines it is possible to make blades with advertising images. It also starts with extremely weak winds and has an excellent ability to adapt to turbulence and rapid changes in wind direction, two important aspects for installation in houses, buildings and sheds. In these settings, the traditional horizontal axis turbines, which for high performance require non-turbulent wind of constant direction, have a low yield. In addition, horizontal axis turbines produce too much noise to be installed on a roof or near a building. The operation of the turbine has been tested successfully by building three small scale prototypes and subsequently testing them in the roof of a building and in a wind tunnel. The blades can be made of various materials, we tested fiberglass, aluminium and fabric. The most powerful and cost-effective version of the turbine was the one with the blades made of fabric. In this case it is sufficient to build a metal frame to be covered with inexpensive fabric resistant to the action of atmospheric agents.
Thus, the first value to potential customers is the high productivity of the turbine. The second is certainly its cost, the new mode of operation of the oscillating blades wind turbine allows an inexpensive design. The realization of the turbine does not require the construction of expensive molds or special processes in specialized companies but it can be done in any mechanical workshop. In this way the company could reach standard margins above the industry average, despite a policy of low-range prices. Finally, thanks to the deep knowledge that the design team has of the formulas used to calculate the fatigue life of mechanical components, APWonder Srl will be able to design the wind turbine for an average life of 60 months without failure.