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This paper experimentally and analytically evaluates the heat rejection/retention performance of a reversible thermal panel (RTP) which can autonomously change thermal performance depending on its own thermal conditions. The RTP is considered as a candidate methodology for thermal control of Venus mission, PLANET-C, in order to save survival heater power. An RTP prototype was tested and evaluated. An analytical thermal model of the RTP was also developed, and basic performances of the RTP were evaluated. Thermal performance of the RTP when applied to the longwave camera (LIR) of the PLANET-C was evaluated with an analytical thermal model as functions of fin deployment directions and rear surface properties of the RTP's fin. The analytical results showed that the RTP can save heater power in comparison to a conventional radiator.

This paper presents thermal-vacuum test data obtained for the JEM MAXI loop heat pipe (LHP) with two separate radiators operating under transient regimes representative of those to be encountered during the flight. The Monitor of All-sky X-ray Image (MAXI) in the Japanese Experiment Module (JEM), on the International Space Station (ISS), is an X-ray camera with wide fields of view to monitor the universe. The LHP collects about 32 Watts of heat dissipated by the detector and thermoelectrics and transports it to two separate radiators, with orthogonal views to space. Propylene is used as a working fluid due to a wide useful operating temperature range from -60°C to +60°C needed for this program. The LHP utilizes two fluid flow regulators to control fluid flow in the two parallel condensers and is equipped with two startup heaters, and three shutdown heaters controlled by six thermostats.

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.

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.

An icing process of a single supercooled-water droplet is focused in the present study. A stationary icing as well as an icing of a moving droplet gives us great insights into the development of an ice-prevention system for engineering purpose. For academic purpose, it gives experimental findings in a two-phase flow. To understand the icing process, we applied a luminescent imaging technique. It uses a temperature-sensitive luminophore and a temperature-insensitive luminophore to create the luminescent water. The luminescent outputs from these luminophores are simultaneously captured by a high-speed color camera. By simply taking a ratio, the temperature distribution can be extracted. In this paper, this imaging system is shown with its temperature characterization. An icing process of a stationary droplet is shown in this paper. Also, a current status of an icing process of a moving droplet is shown.

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.