Design of Horizontal Wind Turbine Blade via Blade Element Momentum Method with 3D Numerical Solution

43 54-43 #$% 1394 2 45 71 ) 2( 3// +, -.( /# 0 1 / ) '()* ) : 9) 67 608 4' ()5 (& $ %&'"!" #$ ) ) (& $ %&'"!" #$ ( (& $ %&'"!" #$ ( 6; 0(<). * 60:'( 6 >?(% '( <!* ( %= <>?;9 %4 5 6 * 78 9 :; 20 * +*,-./0 + 1/ @. 8E F < %> * CD$?8 ) AB </9 * %4 5 6 % 1- *.E (9 6 + * MN +O4/ %= P.O P I- :? J;D K-7 (/ :LD$ GH( (9 J;D?8 10 * Q* % AB %4 5 6 * F * +*,- <*?8 +&* RD F NACA63-?8 V 3 P U P?8 V ) P '( <= * * +* &* <* +O4/.E 7 T/ * X8 5,-.( '( * 4N FX63-137?8 P 4N Riso A1-24 215. '(?,, P % 1- %= * * +*.YZ :[ +8E F <*.?;9 <P( ANSYS CFX + %#! * ]?;9,- ;, /. 8E F $YZ\ *, $YZ 1-,. ^(>:" * P. K= :LD <>?;9 % AB * +*,- %4 5 :6 C 65A(, Design of Horizontal Wind Turbine Blade via Blade Element Momentum Method with 3D Numerical Solution F. Mokhtarinia M.Sc. Graduate, Isfahan University of Technology, Department of Mechanical Engineering M. NiliAhmadabadi Assistant Professor, Isfahan University of Technology, Department of Mechanical Engineering A. Sedaghat Assistant Professor, Isfahan University of Technology, Department of Mechanical Engineering Abstract The purpose of this study is the aerodynamic design of 20 kw horizontal axis wind turbine using blade element momentum with 3D numerical analysis of flow around it. First, the aerodynamic coefficients curves of an airfoil are considered as input. Then, the geometrical characteristics of different blades including chord length, twist angle, relative angle and diameter of blades are calculated using this method. To select the best airfoil as wind turbine blade, power coefficient of 10 different airfoils are calculated and then compared to each other using the blade element momentum method. Also, to improve the performance, three airfoil types called NACA63-215 on the hub section, Riso A1-24 on the midsection and FX63-137 on the tip are used instead of just on eairfoil type from hub to tip. Designed blade is simulated and analyzed in ANSYSCFX software. In order to consider the effects of blades rotation, two domain solutions are used for flow analysis. The surrounded area around the blades is divided into the inner rotating and outer stationary regions. In both design and analysis steps, the results are validated with the other authoritative works in this field. Keywords: Blade element momentum, Aerodynamic design, Wind turbine, Power coefficient, Numerical analysis, Moving Reference Frame. * m.nili@cc.iut.ac.ir : 43

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