Thermal Simulation Analysis And Thermal Design Of Microchannel Coldplate Of Active Phased Array Antenna

From the 1960 s, active phased array antenna(APAA) has been paid a widespread international attention due to its great technical potential, and has been developed and applied vigorously. However, with the continually increasing integration and heat consumption of antenna, its thermal design becomes especially important and prominent. Because the thermal design is relate to antenna’s electrical performance directly and affects the antenna’s function of detection 、 tracking and recognition. The heat consumption of APAA concentrates on T/R module mostly,and antenna array probably has thousands of T/R modules and power transistors, which constitute a huge heating body. Therefore, how to resolve the heat consumption of these T/R modules becomes the most critical problem of antenna’s thermal design. Based on the background, this essay will focus on the research of APAA’s thermal simulation analysis and thermal design. Microchannel heat dissipation techniques will be intensively studied based on one T/R module at the beginning, and a new cold plate will be developed to dissipate the heat. The specific work are as following:(1) T/R modules’ thermal demand and one module’s thermal simulation analysis are studied. Firstly, the structure and the cooling system of APAA are introduced, then the structure and the characterists of T/R module is introduced in details. One detailed module’s temperature field is analyzed with thermal simulation, and three simplified modeling methods of modules are learned. Furthermore, thermal resistance model of T/R modules is proposed and computed to determine the cooling objective of T/R modules and the proper cooling technique.(2) Different factors that affect the pressure drop and the thermal performance of heat sink are studied. Based on the principle of Heat Transfer and Computational Fluid Dynamics, a mathematical model of thermally coupled flow is built. The effect of hydraulic diameter, aspect ratio, porosity and fluid entrance velocity of rectangle microchannel on flow and heat transfer characteristics is analyzed. Based on the basic theory of Factorial Design and Response Surface Method, simulation results are used for evaluating integrated effect of multiple factors and designing the structure parameter and the fluid parameter of microchannel.(3) The influence of topological geometry of flow channel on the thermal performance of heat sink and the pressure drop are studied, and design a cold plate with new channel. Through building cold plate model of APAA, normal flow microchannel’s thermal performance is analyzed. The cold plate with comby fractal microchannel is presented and its temperature field and pressure are analyzed. Compared with normal microchannel cold plate, a new type of cold plate solves the problem of balancing heat dissipation and pressure drop, it meets the heat requirement of transmitters whose heat flow density is 95W/cm2. Finally, the whole APAA with new cold plate is analyzed by thermal simulation analysis.