Experimental and Numerical Investigations on Aerodynamic Characteristics of Savonius Wind Turbine with Various Overlap Ratios

Savonius wind turbine is the simplest type of vertical axis rotor that has a relatively low efficiency. Operation of the Savonius wind turbine is based on the difference of the drag force on its semi-spherical blades, depending on whether the wind is striking the convex or the concave part of the blades. This turbine is being used in various countries around the world due to the simplistic design, cheap technology for construction, and a good starting torque independent of wind direction at low wind speeds. Due to its simple design and low construction cost, this rotor is mainly used for water pumping as well as wind power on small scale. The main goal of this current research is to investigate the aerodynamic performance of Savonius wind turbine. Wind tunnel investigation was carried out to find the aerodynamic characteristics like, drag coefficient, torque coefficient, and power coefficient of three blade Savonius wind turbine rotor models with and without overlap ratio (ratio of overlap distance between two adjacent blades and rotor diameter ,OR = a/D) at various Reynolds numbers. Numerical investigation was also carried out to find those aerodynamic characteristics. For numerical investigation, commercial computational fluid dynamic (CFD) software GAMBIT and FLUENT were used. Afterwards those two results were compared for verification. Three different models with different overlap ratio were designed and fabricated for the current study to find the effect of overlap ratios. The results from the experimental part of the research show a significant effect of overlap ratio and Reynolds number on the improvement of aerodynamic performance of the Savonius wind turbine. At higher Reynolds number turbine Model without overlap ratio gives better aerodynamic coefficients and at lower Reynolds number Model with moderate overlap ratio gives better results.

Name thesis:degree_name

Master of Science in Applied Engineering (M.S.A.E.)

Level thesis:degree_level

Thesis (open access)

Discipline thesis:degree_discipline

Department of Mechanical Engineering

Year dc:date.available

2010

Author dc:creator

• Morshed, Khandakar Niaz

Contributors dc:contributor

• Aniruddha Mitra
• Hung-Ming Cheng
• Scott Kersey

• ETD
• Savonius
• wind turbine
• simplest type
• Wind tunnel investigation
• aerodynamic characteristics

Repository record dc:identifier

https://digitalcommons.georgiasouthern.edu/etd/773

OAI identifier oai:identifier

oai:digitalcommons.georgiasouthern.edu:etd-1773