Thermal Vacuum Testing of Advanced Thermal Control Devices for Flight Demonstration


In Japan, several unique thermal control technologies have been developed. However, there are no opportunity to demonstrate in orbit. Therefore, we have proposed to apply our thermal control devices named advanced thermal control devices (ATCD) to the Innovative Satellite Technology Demonstration Program conducted by JAXA, and accepted to apply to the Rapid Innovative payload demonstration SatellitE-2. In this paper, the test results of the thermal vacuum testing of ATCD are presented. ATCD consists of two types of flexible thermal straps: one is made of high-thermal-conductive material, and the other is made of a fluid-loop, and a re-deployable radiator. The conductive-type thermal-strap (CTS) is made of high-thermal-conductive graphite-sheets and aluminum blocks. The fluid-type thermal-strap (FTS) is made of a ultrathin loop-heat-pipe. The re-deployable radiator named reversible-thermal-panel (RTP) is made of high-thermal-conductive graphite-sheets as a flexible fin, and a shape-memory-alloy as a passive re-deployable actuator. As a result, it was confirmed that the thermal conductance between the two ends of CTS was 0.50-0.55 W/K. As for FTS, it was confirmed that it could operate even after recovering from the freezing condition of the working fluid, and that there was no leakage of the working fluid and no performance degradation under vacuum environment. As the heat load increased, the thermal conductance between the evaporator and condenser increased, and finally a thermal conductance value of 4.1 W/K (at 5 W heat load) was confirmed. For RTP, it was confirmed that the radiator fins were fully expanded to 130� when the SMA actuator reached 30 ? during heating. On the other hand, during cooling, the temperature of the SMA actuator dropped only to -15?, and the fins retracted only to 40�. Furthermore, the temperature hysteresis of the SMA actuator was estimated to be about 40? based on the experimental results.

Satoshi Kajiyama, Nagoya Univ., JP
Takuji Mizutani, Nagoya Univ., JP
Takuya Ishizaki, Nagoya Univ., JP
Kota Tomioka, Nagoya Univ., JP
Hiroto Tanaka, Tohoku Univ., JP
Hiroki Nagai, Tohoku Univ., JP
Kan Matsumoto, WEL RESEARCH, JP
Kenichiro Sawada, JAXA, JP
Yoshihiro Machida, SHINKO ELECTRIC, JP
Kazuaki Matsumoto, KANEKA, JP
Hosei Nagano, Nagoya Univ., JP
ICES107: Thermal Design of Microsatellites, Nanosatellites, and Picosatellites
The 51st International Conference on Environmental Systems was held in Saint Paul, Minnesota, US, on 10 July 2022 through 14 July 2022.
Spacecraft, Spacecraft Thermal Control, Thermal Strap, Loop Heat Pipe, Deployable Radiator, Thermal Vacuum Test