Passive Thermal Control Design Methods, Analysis, Comparison, and Evaluation for Micro and Nanosatellites Carrying Infrared Imager

Abstract

Advancements in satellite technologies are increasing the power density of electronics and payloads. When the power consumption increases within a limited volume, waste heat generation also increases and this necessitates a proper and efficient thermal management system. Mostly, micro and nanosatellites use passive thermal control methods because of the low cost, no additional power requirement, ease of implementation, and better thermal performance. Passive methods lack the ability to meet certain thermal requirements on larger and smaller satellite platforms. This work numerically studies the performance of some of the passive thermal control techniques such as thermal straps, surface coatings, multi-layer insulation (MLI), and radiators for a 6U small satellite configuration carrying a mid-wave infrared (MWIR) payload whose temperature needs to be cooled down to 100K. Infrared (IR) imagers require low temperature, and the level of cooling is entirely dependent on the infrared wavelengths. These instruments are used for various applications including Earth observations, defence, and imaging at IR wavelengths. To achieve these low temperatures on such instruments, a micro-cryocooler is considered in this study. Most of the higher heat dissipating elements in the satellite are mounted to a heat exchanger plate, which is thermally coupled to an external radiator using thermal straps and heat pipes. The effects of the radiator size, orbital inclinations, space environments, satellite attitude with respect to the sun, and surface coatings are discussed elaborately for a 6U satellite configuration.

Transient Thermal Analysis of 1U Modular Cubesat Based on Passive Thermal Control System

“…Therefore, it is concluded that after the usage of the thermal strap, all the electronic components do not exceed the operational limit. S. Selvadurai et al [9] have listed viable passive thermal control design methods for nanosatellites and discussed about thermal straps and multi-layer insulation. in this study a detailed transient thermal analysis is performed on the two potential passive thermal control methods.…”

“…the lightweight nature of aerogel makes it perfect for use with extremely delicate and fragile components. thermal strap is selected as the CubeSat's insulation because it is available in a variety of shapes and lengths based on the demand [9]. thermal straps are well suited for small scale satellites.…”

“…the length and styles of thermal straps can vary depending on the CubeSat requirement. they are flexible and effective thermal linkages because they are made of tiny wires of high thermal conductivity metals or foils [9]. another viable option for thermal management is the use of Multi-layer insulation.…”

EHFE refinement and extension for variable physical Earth radiation in spacecraft uncertainty thermal analysis

“…Attitude Z-axis to ground orientation The input parameters bearing uncertainties, as identified for the purposes of this investigation [10], alongside their average values, are elucidated in table 3. The input parameters are normally distributed and their standard deviation is 0.05.…”

An Innovative External Heat Flow Expansion Formula for Efficient Uncertainty Analysis in Spacecraft Earth Radiation Heat Flow Calculations

“…Since the external heat flux inside the satellite body is zero, the satellite body's reverse surface element is not considered in this study. The uncertainty input parameters selected for this study [29] and their average values are presented in Table 2. The input parameters are normally distributed and their standard deviation is 0.05.…”