A NEW DESIGN FOR A VERTICAL AXIS WATER TURBINE TO TRAP ENERGY FROM SURFACE WATER FLOW

摘要

In this invention a new way to increase the efficiency of a vertical axis water turbine is developed. In this invention the basic idea is to minimise the unwanted drag giving negative torque that is applied on half of the blade assembly. The way we have done it, is to tilt the blade assembly by a particular angle so that half of the blade assembly comes out of water giving almost zero drag and, as there is neglect able drag in air as compared to water the unwanted negative torque will be minimised. The blade assembly will automatically be tilted to an angle due to which half of the blade assembly will come out of water due to which there will be almost no negative torque and hence, the efficiency of the whole system will be increased. The shape of the blades is designed in such a way to get torque as well as tilting forces due to water flow and automatically be tilted due to the forces so as to increase the efficiency of the system. A mechanism in the hub is used to the tilting of the blades. Again a mechanism is invented to avoid the over tilting of the blade assembly. In this invention a mechanism to adjust the height of the blades according to the varying water level is given. Here an electronically controlled hydraulic system is used which senses the water level and automatically adjust the height of the blades. Two possible setups of the proposed design are given, first hanging from a bridge or the other fixed at the bed of any river or ocean.