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The Advanced Land Observing Satellite “DAICHI” (ALOS) is the latest Japanese 4-ton class earth observing platform launched on January 24, 2006. The primary mission of DAICHI is obtaining enormous amount of data for global topographic maps and emergency disaster observation. It is equipped with three remote sensing instruments; the stereo mapping panchromatic imager, the multi-spectral radiometer and the L-band synthetic aperture radar. The thermal control of the DAICHI employed new technologies enabling highly accurate earth observation and gigabit per second mission data handling. A combination of passive and active control techniques stabilizes orbital temperature variation of the truss structure and a large optical bench for observing instruments within less than a couple of degree C. The bus structure is entirely made of low CTE and high thermal conductive pitch-based CFRP instead of conventional aluminum alloy.

The Closed Ecology Experiment Facilities (CEEF) were installed to collect data for estimation of transfer of radionuclides from atmosphere to humans in the ecosystem. The first target among the radio-nuclides is 14C. In order to validate function of material circulation in an experimental system constructed in the CEEF, circulation of air constituents, water and materials in waste was demonstrated connecting the Closed Plant Experiment Facility (CPEF) and the Closed Animal and Human habitation Experiment Facility (CAHEF) of the CEEF, since 2005 to 2007. The CPEF has a Plant Cultivation Module (PCM), which comprises of three plant chambers illuminated solely by artificial lighting, one plant chamber illuminated by both natural and artificial lighting, a space for preparation, and an airlock, and a physical/chemical material circulation system.

Anti- or de-icing of an aircraft is necessary for a safe flight operation. Mechanical processes, such as heating and deicer boot, are widely used. Deicing fluids, such as ethylene glycol, are used to coat the aircraft. However, these should be coated every time before the take-off, since the fluids come off from the aircraft while cruising. We study a hydrophobic coating as an anti-icer for an aircraft. It is designed to coat on the aircraft without removal. Since a hydrophobic coating prevents water by reducing the surface energy, it would be an alternative to prevent ice on the aircraft. We provide a temperature-controlled room, which can control its temperature under icing conditions (-10 to 0 °C). The contact angle and the sliding angle are tested for various hydrophobic coatings. Candidate coatings are tested under super-cooled water spraying and under the representative in-flight icing conditions.

Most spacecrafts flown today are usually covered with multilayer insulation (MLI) blankets as the most efficient thermal control element. In the present study, the thermal performance of MLI blankets was measured by the calorimetric method using a liquid nitrogen cryostat. The purpose of this study is to investigate the influences of various processing on MLI performance for space use. It was found that effect of seam amounts to 50 % of the total heat transfer. The smaller area of the MLI blanket is, the worse is the thermal performance of the MLI blanket.

Aircraft icing is the phenomenon that forms an ice layer on the solid surface by impingement of supercooled water droplets in the atmosphere. In icing on rotor blades, ice is shed from the blade surface by centrifugal force as the accumulated ice grows. The ice shedding on rotor blades is a dangerous phenomenon, but the physical mechanism and properties are unclear, and most simulations have not considered it. Therefore, it’s necessary to establish an ice shedding model for icing simulations. In this study, we proposed an ice shedding model in which the condition for ice shedding is that the centrifugal force exceeds both the adhesion and tensile forces. Centrifugal force exceeding adhesion force expresses adhesion failure, while centrifugal force exceeding tensile force expresses cohesion failure. We also proposed functions of temperature and medium volume diameter (MVD) as adhesion strength and tensile strength for ice shedding judgment.

A Reservoir Embedded Loop Heat Pipe (RELHP) has a liquid reservoir, located in the evaporator, to ease start-up of the LHP. The RELHP is used for heat transfer from the experimental heat load to a deployable radiator (DPR) on the Engineering Test Satellite-VIII (Kiku-8). This DPR is one of the experimental apparatus on the Kiku-8. The RELHP in the DPR has an evaporator, a condenser, transport lines to circulate a fluid and it utilizes the evaporation and condensation of the working fluid to transfer heat. The DPR on the Engineering Test Satellite-VIII (Kiku-8) was launched into a geo stationary orbit by a H-IIA rocket on Dec. 18, 2006. The DPR radiator was deployed successfully and the first start-up of the RELHP in an orbital environment was conducted smoothly. This paper describes the characteristics of the DPR and the RELHP on Kiku-8 in an orbital environment in the first year.