Wood, DavidSun, QiaoMollasalehi, Ehsan2013-01-252013-06-152013-01-252013http://hdl.handle.net/11023/510A major barrier to the acceptance of small wind turbines is that they are perceived to be noisy particularly when mounted on monopole towers rather than traditional guy-wired ones. This research discusses an aspect of noise propagation that has not been studied previously: vibration and noise emission of the tower and consists of three main steps; first, vibration measurements from 24 accelerometers placed on the 10.2 m tower of a Skystream 2.4 kW wind turbine by which natural frequencies and corresponding deflection shapes were calculated. Second, the results from the survey were used to verify the predictions of a finite element model of the tower structure. And lastly, the verified model was placed in the air domains such that the structural vibration generates sound waves. Experiments showed that most of vibration energy is engaged in very low frequency band (10 Hz). It was found that wind itself can only excite first two bending modes. On the other hand, emitted noise from the tower at large distances can be neglected while close to the tower can reach to 30 dB.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Applied MechanicsEngineering--MechanicalSmall Wind Turbine TowerOperational Modal AnalysisFrequency Domain DecompositionTower Noise EmissionAcoustic-Structure Interactionmaster thesis10.11575/PRISM/27804