Study On The Technique Of Thermal Control For Infrared Detectors Of Carbon Dioxide Detector

CO₂ detector is payload of carbon satellite and first greenhouse gas detector of China. It carried two infrared detectors with infrared spectrum of 1610 nm and 2060 nm. Its pose is complex and internal heat loads are pretty much and its running time is long. New challenges put forward by all of the factors to the thermal design. The object of the dissertation is how to use sophisticated thermal design technology to solve thermal design problems of the infrared detectors in order to satisfy its working thermal control requirement.The background and significance of the research are summarized. The technical characteristics and application of the infrared detector, such as meteorology, resource, the earth observation and military remote sensing, etc., were introduced.The structure and working mode of CO₂ detector and infrared detector were introduced. The control target of infrared detector was decisioned through the vacuum dark field environment test and the signal to noise ratio analysis. Combined with the detector assembly and the location of the external heat flux analysis and summarizes the problem of detector module thermal control, the thermal control measures of active thermal control combined with passive thermal control and precision control though active thermal control were raised. Also, the radiating fin was used to enhance dissipate heat. According to the attitude and working mode of the detector, hate and cool case were determined and the thermal analysis was made with the I-DEAS software. It is shown that that the temperature of infrared detector was about-30.9℃^-24.8℃ in hate case and 30.0℃^-26.0℃ in cool case. In addition, the thermal balance test was taken. The results show that the temperature of infrared detector was about-30.1℃^-21.6℃ in hate case and 30.9℃^-29.4℃ in cool case. The temperatures all meet the thermal control requirement. The results of thermal analysis and text showed that the thermal design was feasible and reasonable.At last, the electric-thermal analysis of the infrared imaging electrical box is carried out. The thermal design of the box was taken and the thermal analysis was made with the I-DEAS software. It is shown that the temperature of electronic devices was about 26.6℃²9.6℃. It meets the thermal control target. Also, the thermal design was feasible and reasonable.