• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.529-537
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• 1992

Airlift pumps were tested to evaluate their pumping and aeration capacities. The pumps were 34.5 inch long made of 2, 3, 4 and 6 inch nominal diameter PVC pipes. An one hp air blower was used to supply the air. The air-flow rate was measured by an anemometer type air-flow meter and air pressure was level changes in a water tank from which water was pumped. Aeration by the pumps was tested by the standard aeration test method with the center of pump outlet positioned 3 inches above water surface. Oxygen concentrations in water were measured to determine aeration rate. As pumping head increased by water level draw-down in the tank water flow decreased while air flow increased. The reduction rate of water flow was higher with 4 and 6-inch pumps. Small pumps showed very minor changes in the reduction. Aeration rates were similar among 3, 4, and 6 inch pumps. With one hp air blower 6-inch pump at the minimum pumping head achieved the best performance in terms of water circulation.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.2
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• pp.170-177
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• 2013

This study is focused on the shape design and flow analysis on a 200 W-class Gyromill type vertical axis wind turbine rotor blade. Single tube theory is adopted for the shape design of the turbine blade. 2-dimensional CFD analysis is conducted to examine the turbine performance with basic shape, and then 3-dimensional shape is determined from the examination of the performance. By the CFD analysis on the 3-dimensional shape of the wind turbine, performance of the turbine is examined and also, shape of the wind turbine rotor blade is determined accordingly. From the results of this study, a 200 W-class Gyromill type vertical axis wind turbine rotor blade is designed and the reliability of the design method is confirmed by CFD analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.9
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• pp.1087-1094
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• 2012

This study deals with structural analysis and testing under loading conditions calculated by computational fluid dynamics for a small composite blade that is utilized in a dual rotor wind turbine system. First, the aerodynamic forces were analyzed at the rated and cutout wind speed to identify the bending moment distribution along the blade length in previous research. Then, full-scale structural tests were conducted according to IEC 61400-2 to evaluate the structural integrity of the composite blade. These results were compared with finite element analysis to identify the accuracy of the structural analysis. Based on these results, it was revealed that the existing blade has a very high safety margin. Then, the layup of the composite blade was redesigned and analyzed using finite element analysis to achieve structural integrity and economic efficiency.