Vibration and acoustic numerical analysis of gregorian type communication antenna planted on communication satellite

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2020
Karaoğlu, Onur Kaan
The acoustic load during lift-off of the spacecraft rockets is one of the most destructive loads especially for the light and large space structures. This thesis mainly focuses on vibro-acoustic behavior of a large composite reflector satellite antenna. The study starts with manufacturing processes, material properties and design criteria of the antenna which is Gregorian type with two reflectors. Then, Finite Element Model (FEM) of the antenna which is prepared in HyperMesh is analyzed structurally with calculation of modal and frequency response in MSC. NASTRAN. The FEM model and results are adjusted by using the sine-sweep test results performed on a modal shaker. After obtaining proper FEM model, vibro-acoustic numerical model is constructed and solved in MSC. ACTRAN. One of the strongest parts of this thesis is presenting acoustic test results performed in a reverberant chamber which provides the diffuse sound field. In summary, this thesis presents manufacturing processes of satellite reflector antenna and examines the vibration and acoustic test responses and FEM results with their comparisons.

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Citation Formats
O. K. Karaoğlu, “Vibration and acoustic numerical analysis of gregorian type communication antenna planted on communication satellite,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2020.