| Electronic equipment is a kind of electromechanical system, and the electromechanical coupling problem is the bottleneck which constrains the improvement of existing electronic equipment and the development of the next generation equipment. With the support of several national key projects, based on the previous work, this paper researches the coupled multifield problem and integrated optimization design on the study of reflector antenna and electronic equipment enclosure, which are two kinds of typical electronic equipments.Based on the electromechanical coupling model of reflector antenna proposed by previous scholars, for the problem of large computation in analysis of the coupling model, a new solution is proposed which could improve analysis efficiency and precision. Firstly, the transformation matrix between structures grid and electromagnetic grid is derived. Secondly, the finite element shape function of the structure grid is used to interpole phase difference of aperture surface. Thirdly, different formulas of different structure grid for numerical integration are derived. Finally, the correctness and effectiveness of the new solution is proved by some numerical simulations and experiments.For the problem of thermal deformation of ground reflector antenna due to solar radiation , which is a kind of system error, the heat flux from solar on antenna surface is calculated firstly. Secondly, the temperature distribution of antenna is obtained by FEM, and a temperature experiment proved the temperature results. Thirdly, thermal-structure analysis was proceeded by FEM. Finally, electronic parameters of the antenna were calculated by coupling model. Another surface quality problem of reflector machining, is a kind of random error. Fractal function is used to model surface texture. Microscopic surface texture is introduced to the coupling model and then calculates electronic performance. The effects of different amplitude, density and roughness of the reflector texture to antenna's far field patterns are studied. These results could be referenced in engineering practice.For the separation problem of electromagnetic and structure design of reflector antenna, based on the coupling model, a new electromechanical integrated optimization model of reflector antenna is established. The structure parameters include feed support structure, so the antenna structure could be designed as a entirety. The examples of tipical 8m and 40m antennas in some project show that the electromechanical integrated optimization results are much better than the tradition structure design, and the results indicate the rationality and effectiveness of the integrated optimization.Address to numerical simulation of shielding effectiveness and leakage electromagnetic field of electronic equipment enclosure, server influence factors are researched in the view of multifield coupling, including structure parameters(holes, slots and so on), contact seam/conductive rubber, structure deformation and temperature. In consideration of the enclosure which will deform due to impact and vibration, and temperature will affect the features of electromagnetic components in practical working, the three fields coupled model of electronic equipment enclosure is established. Transfer impedance is used to compute electromagnetic parameters of contact seam/conductive rubber during solving the coupled model. The comparison between simulation data and the experiment data shows that the three fields coupled model is correct.Against the separation problem of electromagnetic, structure and thermal design of enclosure, basis on the three fields coupled model, a integrated optimization model is proposed. Finally, the optimization method is applied to an engineering case, to optimize the structural parameters, and the designed scheme is greatly improved in structure strength, ventilation and shielding effectiveness, and the results indicate the advantage of the integrated optimization.
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