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Regarding radar antenna working in the open-air, its wind load is one kind of primary payload which must be considered because it not only influences radar antenna’s structural strength, but also causes the distorts of emitting area and the back-frame, which influences the antenna’s precision seriously and creates focal diverge. How to analyze and compute wind load to radar antenna has become one of important links of antenna loads analysis.The wind load research’s method mainly includes the theoretical analysis, and computational wind engineering. With the development of the computer and computational fluid dynamics, the computational wind engineering has replaced spot measurement and wind tunnel simulation gradually due to its effective and more accurate method. This article utilizes the principle of the computational wind engineering and numerical simulation to analyze wind load to radar antenna.The first, aimed at radar antenna, the article elaborates the aerodynamics characteristic and numerical simulation elementary theory, such as wind characteristic, turbulence model, grid technology and so on. The more details of researches are discussed such as grid, boundary condition, turbulence model, referred pressure, and calculation parameters with regard to numerical simulation.The second, based on the software of FLUENT, variant computational areas are adopted in tail length, inlet length and blockage ratio respectively. Then the better computational areas are to be ascertained by analyzing the change of wind load.The third, the influence that grid quantity affects the computed result is studied to determinate relatively good grid quantity scope.The last, the effects of some parameters, such as working height, wind velocity, wind direction, working obliquity on characteristics of wind loads are studied based on the modeling method and the grid division’s research. At the same time physical quantity condition values are obtained for the deep research to radar antenna’s wind load characteristic.The series of research not only have important drawing lessons to the radar antenna wind load’s numerical simulation method in the actual project application, also provide the beneficial reference for antenna structure’s design.
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