الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis aims to analyze experimentally and numerically the performance of the Savonius wind turbine with a modified blade shape/profile. The wind turbine rotor introduced consists of two hock shape buckets connected by a Batch/arm with different bucket orientations. Blades of cross-section with different thicknesses are considered. The simulations are carried out using the three-dimensional incompressible unsteady Reynolds Average Navier Stokes (RANS) equations along with the RNG k-ε turbulence model. The
numerical model is based on RANS equations that are solved by employing ANSYS Fluent 17. The results indicate that the RNG k-ε turbulence model achieves a good prediction of the rotor performance. In comparison with the literature six rotor models are investigated to explore the effect of rotor shape along with blade thickness on the wind turbine performance. The first rotor Model (M1), consists of two buckets connected by the 43 mm Batch arm. The second rotor model M2 is the same as the rotor model M1, however with
a reduction in the bucket length at its outer edge. The third rotor model in this study, M3, has two buckets hooked towards the outer edge of the rotor blade, with thickness of 2 mm. The fourth rotor model M4 has the same features of M3 except the batch arm length, which is reduced for model M4 to 2.15 cm. While, the previous models have the rotor arm parallel to the blade chord, the fifth and sixth models have arm batch perpendicular to the blade
chord. It is revealed that the rotor model with a blade thickness of 2 mm and bucket orientation with a parallel arm-bucket, Model 3, has the best performance among the tested rotors. The thinner blade has less deformation in the profile equation obtained at its
centerline. The best wind turbine rotor, model 3 which obtained from the numerical computations has been then fabricated and tested experimentally, to ensure its performance characteristics. The comparisons reveal that the model M3 has the highest power coefficient as the blade is hooked outwards. The peak power coefficient of this model is 0.164 at λ = 0.55. The flow characteristics of the tested rotor models in terms of pressure
and streamline contours are explored. It is found that Model M3 has relatively lower pressure on the front surface of the returning blade at a rotor angle of 0°, with almost similar pressure on the front of the advancing blade of all rotors. This reduces the negative drag
created on the M3 rotor, the average positive drag created on the M3 is higher. To examine the starting ability of the present rotors, the static torque coefficient is presented. The rotor
model M3 shows positive values for all rotor angles with maximum 𝐶𝑇𝑠 of 0.45 which reveals the high starting ability of the present rotor.