Lee Chan Hee, Seo Seong-Won, Park Dong Kyou, Lee Kwon-Yeong
Handong Global University, 558, Handong-ro, Heunghae-eup, Buk-gu, Pohang-si, Gyeongsangbuk-do, 37554, Republic of Korea.
Korea University of Technology and Education, 1600, Chungjeol-ro, Byeongcheon-myeon, Dongnam-gu, Cheonan-si, Chungcheongnam-do, 31253, Republic of Korea.
Heliyon. 2023 Oct 13;9(10):e20925. doi: 10.1016/j.heliyon.2023.e20925. eCollection 2023 Oct.
In this research, the geyser phenomenon occurring in a small-diameter two-phase closed thermosyphon (TPCT) was observed and the instability of the device was discussed. Geyser phenomena interfere with the natural circulation of internal working fluids, increasing the thermal resistance of the system and contributing to the instability of the device. This study attempts to improve the thermal performance and stability of the system using cellulose nanofiber (CNF) fluid as the working fluid. The use of CNF fluid was observed to reduce the magnitude of temperature change inside the evaporator of the TPCT significantly. Moreover, it improved the local boiling heat transfer coefficient by 3.1 %, 87.3 %, and 181.2 % on average when the filling ratios are 0.25, 0.5, and 0.75, respectively. Studying the local heat transfer performance and instability will be helpful in designing a more stable TPCT efficiently. Additionally, the findings of this study can be applied to solar thermal power generation or heat pipe research for cooling strategies in computing servers, depending on the input heat load.
在本研究中，观察了小直径两相闭式热虹吸管（TPCT）中出现的间歇泉现象，并讨论了该装置的不稳定性。间歇泉现象会干扰内部工作流体的自然循环，增加系统的热阻，并导致装置的不稳定性。本研究试图使用纤维素纳米纤维（CNF）流体作为工作流体来提高系统的热性能和稳定性。观察到使用CNF流体可显著降低TPCT蒸发器内部的温度变化幅度。此外，当填充率分别为0.25、0.5和0.75时，它平均可将局部沸腾传热系数提高3.1%、87.3%和181.2%。研究局部传热性能和不稳定性将有助于高效设计更稳定的TPCT。此外，根据输入热负荷，本研究的结果可应用于太阳能热发电或用于计算服务器冷却策略的热管研究。
