الفهرس 
World Energy Strategy
Airfoil selectionOnly 14 pages are availabe for public view
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Abstract
The airfoil shape design has an influence on the vertical axis wind turbine performance. The present study is beginning with investigation of airfoil maximum thickness on the vertical axis wind turbine performance for five standard airfoils NACA (0009, 0012, 0015, 0018 and 0021). Double multiple streamtube numerical model method, with Q-blade software, is used with three straight blades, chord length 0.11 m, height 2 m and radius 0.715 m, with the boundary condition close to location of study, Egypt, where the range of wind speeds is of 3-9 m/s, the study is performed at the averaged wind speed of 5.8 m/s. Results show that as thickness increase the maximum coefficient of power increase, as it goes from thin airfoil NACA 0009 to the thicker airfoils, where NACA 0021 shows slightly better results than NACA 0018 at tip speed ratio from 1.11 to 3.11, NACA 0021 airfoil is used as base model for modification, where a computational fluid dynamics turbulence model shear-stress transport kω-SST is used to study the aerodynamic loads, after it is validated with respect to experimental data at reynolds number 1.80 x105 for chord length 0.14 m and width 0.28 m, the trailing edge end curvature of NACA 0021 is altered in design shape to be inflated to 25%, 50% and 100% scaled of the leading-edge curvature to the maximum thickness, at the same chord length and same maximum thickness. Numerical investigation, of the same validated shear-stress transport kω-SST turbulence model, is used to study the effect of airfoil trailing edge inflation on the aerodynamic characteristics at the same experimental data of validation , the results show that, the new modified airfoil with 100% inflation delays the flow separation to higher angle of attack to 10% and increases the maximum lift coefficient about 40% compared with the base airfoil NACA 0021, final stage of current study to use Double multiple streamtube numerical model method for 100% inflation modified airfoil model to compare the power coefficients at the same wind turbine dimensions and wind speed of the test, 5.8 m/s. where comparing the results with the base airfoil NACA 0021, shows that, there is 20% enhancement in Power coefficient at tip speed ratio of 3.11, which is indication of better performance for the modification.