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This paper describes the thermal design, analysis and test of a Microgravity Vibration Isolation System (MVIS) that will ensure the active isolation of the European Space Agency’s Fluid Science Laboratory (FSL) payload from vibration induced by the International Space Station (ISS) structure. The FSL is equipped with optical and electronic devices that are very sensitive to vibration, thermal distortion, temperature change and Electro Magnetic Interference (EMI). The MVIS has to provide a vibration attenuation of −40dB within the range of 0.1–100Hz without inducing thermal or electromagnetic interferences. The sensitive FSL instruments are mounted in a floating structure called the Facility Core Element (FCE), whereas the rest of the FSL electronics, mechanics and cooling systems are fixed to the International Standard Payload Rack (ISPR).

The Phoenix Mars Lander is scheduled to be launched in August 2007 and will land in the northern Vastitas Borealis region. The lander is equipped with a suite of instruments designed to investigate the mineralogy and geochemistry of the soil and to study the atmosphere. The Canadian Meteorological Instrument (MET) will measure the location and the extent of clouds and the distribution of scatterers in the atmosphere as well as measuring the air temperature and the barometric pressure. The MET will provide Canadian scientists with a unique opportunity to study the Martian atmosphere and enhance our understanding of the planet in key areas of Canadian expertise. The MET instrument is composed of multiple elements in order to fulfil the science objectives. The MET Light Imaging Detection and Ranging (LIDAR) will probe the atmosphere by sending out laser pulses and measuring the backscattered returns.

This paper presents experimental results regarding a new approach to smart radiator devices (SRD) employing a smart, integrated thin-film structure based on V1-x-yMxNyOn that can be applied to existing thermal blankets such as Kapton or to thermal radiators such as Al. The smart coating facilitates thermal control by dynamically modifying the thermo-optic characteristics of the underlying substrate in response to the ambient temperature and/or a control voltage. This methodology has significant advantages over competitive technologies in terms of weight, cost, structural simplicity, and integration with the space structure. The effective emissivity of the film/substrate structure can be reduced dynamically by changing the behavior of the smart coating from insulator to metallic. High quality VO2 films have been prepared using a hybrid reactive laser ablation technique.

Heat pipes, loop heat pipes and capillary pumped loops are heat transfer devices driven by capillary forces with high-effectiveness & performance, offering high-reliability & flexibility in varying g-environments. They are suitable for spacecraft thermal control where the mass, volume, and power budgets are very limited. The Canadian Space Agency is developing loop heat pipe hardware aimed at understanding the thermal performance of two-phase heat transfer devices and in developing numerical simulation techniques using thermo-hydraulic mathematical models, to enable development of novel thermal control technologies. This loop heat pipe consists of a cylindrical evaporator, compensation chamber, condenser along with vapor and liquid lines, which can be easily assembled/disassembled for test purposes. This laboratory setup is especially designed to enable the visualization of fluid flow and phase change phenomena.

This work presents the results of an experimental High Performance Miniature Loop Heat Pipe. The evaporator utilizes a wick structure with the non-inverted meniscus evaporation concept, which allows using high thermal conductivity materials for the evaporator case and capillary wick structure, and hence will further reduce the thermal resistance between the evaporator elements. The heat fluxes at the evaporator can therefore be significantly higher than that of a LHP using inverted meniscus evaporation approach. Tests were conducted in the Material and Thermal Laboratory at the Canadian Space Agency. The evaporator heat input cross-section area was 2.4 cm2. When water is used as the working liquid the heat transfer rate has reached values as high as 215W, corresponding to a heat flux density of 90W/cm2 (temperature drop between heat source and LHP evaporator was ∼7°C). Working temperature oscillations (with amplitude ∼2-10°C) were observed for steady state regimes of LHP operation.