Mechanical Performance Analysis And Optimization For Blade Structure Of Tidal Current Energy Turbine

Blade is the main energy-catching part of tidal current energy turbine,good design,light quality and stable performance of the blade plays an important role in the operation of the turbine unit.At present,investigations on the structural design of turbine blades is mostly focused on the shape design and material laminated design,and the optimization design for the blade is only limited in the airfoil optimization design,a few literatures are focused on the internal structure optimization,thus resulting in material waste and high cost.Therefore,it is of important engineering significance to carry out the structure analysis and optimization for the blade of tidal current energy turbineThis paper investigates on the blade structure of the 100 kW tidal current energy turbine.Mechanical performance analysis and optimization design of blade structure for two kinds of materials(steel and composite materials)and two section forms(keel beam and box girder)are analyzed by the finite element analysis method.The main work contents are as follows:1.Summarize the structure design theory of turbine blade,and put forward two kinds of blade profile form which is the steel keel with a spindle(keel beam)and box type composite material,design the corresponding detail structure,and establish the corresponding finite element model in ANSYS Workbench.2.Carry out structural analysis for the steel blade and composite blade,the analysis including static analysis,modal analysis and stability analysis.Research the distribution rule of structural stress and deformation of blade,the main vibration mode of blade and the damage form when the blade buckling,compare stress characteristics of two kinds of section form the blade.3.Optimize the steel blade and composite blade,the quality is takens as the objective function,the quality of the steel blade is reduced by 10.02%,and the quality of composite blade was reduced by 14.02% after optimization.Moreover,carry out static analysis,modal analysis and buckling analysis for the optimized structure,the numerical results show that the strength,stiffness and stability of the steel and composite blades can meet the requirements.Besides,the sensitivity to buckling of the blade was analyzed,design variables that most sensitive to stability of the blade are put forward.At last,suggestions on final blade structure are made,which provide reference for the design for blade structure of the hundred kilowatt tidal current energy turbine in China.