THERMAL PERFORMANCE ANALYSIS OF ELECTROSTATIC SWITCHED RADIATOR FOR SATELLITE

The temperature of the satellite in orbit is determined by the balance between its energy absorption of radiation（mainly from the sun and other star）and loss of energy via radiation to the cold-black universe.Therefore,the material characteristic of the satellite surface is very important.If the absorbing-radiating ratio of the satellite surface material is reasonable,the balance temperature is suitable for equipment on satellite.However,because of the transformation in flight attitude,orbit,satellite equipment,special environment（such as the moon and the deep space exploration）,the heat transfer around satellite change greatly.In these conditions,the thermal control devices with fixed absorbing-radiating ratio like OSR have the serious limitation in satellite thermal control design and performance of the entire satellite.In this paper,we analyze an active thermal control device,termed Electrostatic switched radiator（ESR）.ESR is a variable thermal conductivity device which uses electrostatic hold-down of a high emissivity composite thin film to control satellite temperature.The electrostatic hold-down switches the mode of heat transfer from conduction to radiation.The effect is a large change in apparent emissivity.Application of the voltage results in the high emissivity state while removal gives the low emissivity state.The ESR has the advantages of simple structure,high reliability and fast change of emissivity compared to the electrochromic device and thermochromic device.In this paper,we find out several ways to improve the thermal performance of ESR.All these methods have general guiding significance to the ESR fabricating.