Design of Wind Turbine Blade with Thick Airfoils and Flatback and its Aerodynamic Characteristic
large-scaled blade has posed many problems related to design and production. After introducing the features of blade with thick airfoils and flatback, based on relevant parameters of Huaren 100 kW wind turbine, the paper designed blade with thick airfoils and flatback, introduced blade parameter design, and analyzed the aerodynamic performance of blades using GH bladed software, obtaining the relationship between power output of wind turbine with blade tip speed ratio Cp. Furthermore, it analyzed the aerodynamic performance of original design blades, modified blades and Huaren 100 kW blades, and assessed the aerodynamic performance of modified blade.
Structural Analysis of Large-scale Composite Wind Turbine Blade Based on ANSYS
Based on the ANSYS software,the structural analysis of a kind of 1500kW large-scale composite wind turbine blade which applied in GL3A wind farm was carried out. The analysis results show that the vibration modes of this blade are mainly presented as first flapwise mode and first edgewise mode,the frequencies of the vibration are respectively 0.86Hz and 1.59Hz. At the action of ultimate flapwise loads,the FEM analysis results show that the blade tip deformation is 8.445m,while the blade tip deformation of the full scale blade under static test is 8.12m,so the deviation between the calculated and tested value of the blade tip deformation is only 3.8%. Moreover,the calculated maximum tensile stress and the compressive stress are 228MPa and 201MPa,while the tested tensile strength and compressive buckling strength of the glass-fiber/epoxy composite are 720MPa and 380MPa,respectively. Consequently,the percentages of the calculated maximum stress and the tested ultimate strength are respectively 31.7% and 52.9%.
Laminar heat or mass transfer in rectangular channels and in cylindrical tubes for fully developed flow: comparison of solutions obtained for various boundary conditions
Abstract A comparison is made of results obtained with various boundary conditions at the wall of the channels. By comparing blood Sherwood numbers for finite wall resistance with those for constant concentration boundary condition only a small variation is found for various points along the blood channel.