Sensitivity analysis of thermal design parameters for focal plane assembly in a space spectral imaging instrument

Abstract

There are deviations between real parameters and thermal design parameters on thermophysical attribute of focal plane assembly (FPA). The parameters are difficult to be determined accurately and the thermal design scheme will be affected with the values of the parameters. The thermal design problem of FPA is described by means of system sensitivity theory. The in-orbit heat balance equations are established, and the thermal design parameters, which might affect the temperature distribution of the FPA, are given. As an example, the sensitivity of thermal design parameters is analyzed for a FPA in a space spectral imaging instrument. A basis to determine the structural and thermophysical parameters for FPA is gotten, furthermore, an analytical method is provided for reliability validation of thermal design and operating reliability on orbit. It is shown that contact heat-transfer coefficient between mounted surfaces and surface emissivity are the main parameters affecting mean temperature of Charge converse device (CCD). The power of the inner heat source, thermal conductivity and inner contact heat-transfer coefficient are the primary parameters affecting temperature difference between CCD and the heat-transfer block. The thermal test is set up, and it is illuminated that the sensitivity analysis strategy based on the thermal design scheme is effective and feasible.