Phased Array Antenna Thermal Analysis And Vibration Analysis

As a decisively vital subsystem of Phased Array Radar, Phased Array Antenna has high technical content and capital outlay. However, Phased Array Antenna is electronic equipment with high power, high structural density tends to generate more heat in a structure and cause serious thermal problem. Temperature fluctuations caused by either power transients or environmental changes, along with the resulting thermal expansion mismatch between the various materials, results failure of devices and components. In addition, vibration is also the main reasons which can induce failure of antenna. At present, finite element simulation has been the key technique in failure analysis of military electronic products. It not only can reach adequate precision, but also can save cost and time of experiment to do finite element simulating analysis to many complex physical problems of Phased Array Antenna.In this dissertation, thermal reliability and vibrational reliability of Phased Array Antenna have been researched by experimental means of ANSYS. Finite element models and APDL programs have been built to conduct thermal, thermal-mechanical and vibration modal analysis. The aim of these studies are trying to find some possible reasons and trends which affect the reliability of Phased Array Antenna and give some useful suggestions for the antenna design.The main studies are as follows:1. Thermal geometrical models and finite element models of vital device, subpart, whole structure of Phased Array Antenna were built.Thermal simulation and thermal-mechanical simulation were performed, gaining the rule of temperature field distribution, thermal stress field and thermal deformation distribution.When doing the analysis of subpart, the influence of size changing of phased shifter geometrical model to the thermal analysis of subpart was mainly studied.2. For structures which are large-scale or made up of many same substructures, The substructure thermal analysis is one of efficient and applied Methods to do thermal analysis, with advantages of saving computing resource and time. The application of substructure thermal analysis was performed to the subpart of antenna. The selection method of master degree of freedom in substructure temperature condensation for thermal analysis was studied deeply. The influences of distribution and number of master degree of freedom was mainly discussed.3. Vibration geometrical models and finite element models of vital subpart and whole structure of Phased Array Antenna were built. Modal analysis was conducted to determine the dynamic parameters including natural frequencies and modal shapes. Finally, comparison of computing results respectively from antenna substructure modal analysis method and antenna whole model modal analysis method was done.