Studies of Novel Vortex Wind Anemometers with Wind Direction Adaptability

• Main Authors: Han-YuTsai, 蔡寒羽
• Other Authors: Tzong-Shyng Leu
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/tft3c8

碩士 === 國立成功大學 === 航空太空工程學系 === 104 === This thesis uses the vortex shedding phenomena for develop a new wind anemometer. This vortex wind anemometer has the advantages of simple cylindrical shape with long-term stability, well repeatability, low maintenance costs, and absence of moving parts. However, the development of the new vortex wind anemometer also has to face the challenges, including the non-stationary atmospheric turbulence field, the unknown wind direction. Therefore, one must consider the wind adaptability for the new vortex wind anemometer. To find the locations on the cylinder where signal can be analyzed is necessary. In this research, two research methods, CFD numerical simulation and wind tunnel experiments are used to study the new vortex wind anemometer. In the CFD numerical simulation, the assessment results are divided into “Three Holes” and “Four Holes” configurations on the cylinder surface. The “Three Holes” configuration is using pressure difference signals from three pressure holes on the cylinder surface, and the “Four Holes” configuration only using two signals on the cylinder surface, to analyze wind speed for different wind directions. In the wind tunnel experiment refer to the CFD result. After the raw signal transferring by filter process, if its SNR is higher than 1, deciding the raw signal is usable. The result shows that the Four Holes signal quality is better than “Three Holes” configuration. In other hand, the wind tunnel experiment presents that both “Three Holes” and “Four Holes” configurations of the new vortex wind anemometer can measure wind speed from any wind direction. One can also try to determine the wind direction according to pressure coefficient measurements from “Three Holes” and “Four Holes” configurations. The results find that the wind direction resolution of Four Holes is higher than Three Holes. Therefore, it is suggested use the “Four Holes” configuration for the new vortex anemometer in this stud.