Thermal Performance of Additively Manufactured Three-dimensional Oscillating Heat Pipe with Check Valves in Various Orientations



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2024 International Conference on Environmnetal Systems


An oscillating heat pipe (OHP) is an attractive thermal control device, which has high heat transport capability and enables heat transfer from narrow space. The Japan Aerospace Exploration Agency (JAXA) has developed an OHP with check valves (CVOHP) for space applications. CVOHPs are assumed to be used in three-dimensional shapes, such as L shape, U shape, or more complex ones in practical applications. Recently, metal additive manufacturing has been focused as a promising solution to fabricating CVOHPs with complex three-dimensional shapes. In this study, we evaluated the thermal performance of the additively manufactured CVOHP (AM-CVOHP) with a U-shape in various orientations: horizontal, bottom heat, top heat, and orientation where the middle section of the U-shape comes to the top and bottom. The test results showed that the AM-CVOHP operated stably at the orientations except for top heat orientation. In horizontal, bottom heat, and orientation where the middle section of the U-shape comes to the bottom, the AM-CVOHP could transport heat up to 200 W, and its effective thermal conductivity was in the range from 3000 to 7000 W/mK. As for the top heat orientation, the maximum heat transport decreased to 100 W, and the effective thermal conductivity was lower than the other orientations. Also, when the AM-CVOHP was heated after being kept at the top heat orientation for a long time, startup failure was observed. As described above, the U-shaped AM-CVOHP operated well in most orientations except for top heat orientation. We need further investigation to improve the operating characteristics in top heat orientation.


Makiko Ando, Japan Aerospace Exploration Agency (JAXA), Japan
Atsushi Okamoto, Japan Aerospace Exploration Agency (JAXA), Japan
ICES201: Two-Phase Thermal Control Technology
The 53rd International Conference on Environmental Systems was held in Louisville, Kentucky, USA, on 21 July 2024 through 25 July 2024.


oscillating heat pipe, check valve, additive manufacturing, three-dimensional, orientation