Through the study found that the vertical wind turbine power coefficient theory limit reached 0.64 and 0.593 is more than the limit Bates. But in practical application, the vertical wind turbine of Cp value generally lower than the horizontal axis, this is mainly because of the vertical axis wind turbines aerodynamic than horizontal axis is much more complex.
But compared with horizontal axis wind turbine, vertical wind turbine has a prominent advantage, mainly is of simple structure, low cost, and vertical wind turbine no to the wind device, therefore in manufacture and maintenance costs will further.
Vertical wind turbine can be divided into two classes, a simple type of lift wind machine, another is the resistance type wind turbine. Wind resistance type during the upwind side suffered a huge resistance, in order to reduce the resistance, the people in the upstream of upwind side mount wind shield or shield plate, produced good results.
In fact, lift type wind turbine are higher efficiency, is that it use is blade lift, is the pressure difference between the blade pressure side and suction surface, or pressure; The resistance type is directly using the kinetic energy of the wind. Due to use pressure rather than directly using the kinetic energy potential is much bigger, make full use of the wind pressure difference to produce lift is to improve the resistance type vertical wind turbine efficiency is the basic way.
Resistance type vertical axis wind turbine performance is improved, as a medium and small type roof and other off-grid applications will become city of ideal choice; Because the machine is very low center of gravity, more suitable for amplification into many megawatts of mainframe, will be in windy area and offshore wind farms become more cost-effective optimization models; And in the wind, the vertical wind turbine will present a efficient, reliable working condition.http://www.titanwindturbine.com/