Key Technology Horizontal Axis Tidal Current Energy Generation Device Blade Design

Tidal power is one of renewable green energies. There have been largeamout in our country in contradistinction to others. Generating electricity byusing tidal power can fundamentally relieve the pressure of lack of energyBlade, the first part of energy conversion, is the key component forcapturing energy of the horizontal-axis-tidal-current-power-generation device. Agood designed blade will directly effect to the power generation efficiency. Thewater flow velocity, one of many blade design parameters, is important anddecided by flow velocity which is changing all the time. Therefore, it’s vital tochoose blade design flow velocity that will affect the efficiency of capturingenergy, the form of blade and processing cost, etc. There is no scientific methodto choose it so far around the world. Currently, the blade design velocity isconsidered as an average of max velocities at local area. In that case, theobjective is to obtain the maximum output of power. However, there appear fewmaximum flow velocities in a tidal circle, in most of which the blade works atthe situation of low flow velocity and low efficiency. So this paper focuses onthe study of choosing blade design flow velocity and design method of bladeand proposes a method to calculate the optimum flow velocity range whichmakes the blade has better capture efficiency instead of some velocity point.First of all, we study the blade design flow velocity. Through analyzing thewater velocity variation of the experimental site and considering the theory ofblade energy capturing, we propose a method to calculate blade design flowvelocity. Secondly, we study the theory of blade design. We combine the blademomentum theory, Wilson’s optimization design method and Shen’s revision ofmodel to build a math model for tidal energy capturing blade, using Matlabsoftware to program general calculation of blade form for horizontal axis tidalcurrent power-generation devise. Finally, we test the device under sea condition.We design and manufacture two kinds of blades through regular way andrevision. We set up a platform for performance test to compare the experimentresult of two blades. In conclusion, the revised way is proper and valid.