Keywords:Blade Element Momentum Theory, Thai Sail Windmill Simulation, Wind Turbine Efficiency, Validation
Thai sail windmill (TSW) is a local machine of Thailand now using for pumping brine to the salt farms. TSW is a horizontal axis wind turbine that the blade is a triangular shape made of canvas. Traditional TSW efficiency is typically about 10-17%. However, it has been now developed and augmented its efficiency until 30-35%. Therefore, due to a low construction cost, an uncomplicated structure and a higher efficiency, these things encourage TSW more interesting for research. By the way, the wind turbine simulation is one significant research topic because the accurate simulation can bring about the evaluation of torque, power and efficiency correctly in another condition without the experiment. So, the simulation is very helpful to design the blade of the wind turbine. The purpose of this article is to perform the TSW simulation based on the blade element momentum theory to appraise the efficiency and to validate results with the experiment data. The efficiency evaluation would be regarded by 4 manners of the tip pitch angle as follows: 5, 10, 15 and 20 degrees. The results show that the TSW efficiencies estimated by the simulation are accurate at the tip pitch angle of 10, 15 and 20 degrees in the range of tip speed ratio of 2.0-3.5 whose average percentage error is about 7.0%.
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