WIND EFFECTS ON ANTENNA STRUCTURES

Abstract

The present research work was an attempt to fill the gaps in the available research information on the wind loading aspects of antenna structures in general and of paraboloidal dish antennas in particular. The work carried out comprises of both experimental and analytical studies. In the experimental part, detailed wind tunnel investigations were made out on rigid paraboloidal antenna dish models under a simulated boundary layer windflow condition. The main parameters studied were geometric ratio (f/D ratio) and orientations of the antenna dish with respect to wind. A comprehensive and detailed wind pressure data, in the non-dimensional form of pressure coefficients has been presented for the paraboloidal dish antennas. These experimental results were further analysed and presented as force and moment coefficients with respect to the wind and body axes systems. In the analytical part, a detailed static analysis of a typical dish and its back-up structure has been carried out ,for various wind loading conditions, to present a detailed force-moment data for the dish and member forces and nodal deflections data for the back-up structure. The analytical part also includes a detailed dynamic analysis, both free and forced vibration, of this back-up structure to determine its dynamic characteristics.