Heat transfer characteristic of a closed two-phase thermosyphon with enhanced boiling surface is studied and compared with that of a copper mirror surface. Two-phase cooling improves heat transfer coefficient (HTC) a lot compared to single-phase liquid cooling. The evaporator surfaces, coated with a pattern of hydrophobic circle spots (non-electroplating Ni-PTFE, 0.5∼2 mm in diameter and 1.5–3 mm in pitch) on Cu substrates, achieve very high heat transfer coefficient and lower the incipience temperature overshoot using water as the working fluid. Sub-atmospheric boiling on the hydrophobic spot-coated surface shows a much better heat transfer performance. Tests with heat loads (30 W to 260 W) reveals the coated surfaces enhance nucleate boiling performance by increasing the bubbles nucleation sites density. Hydrophobic circle spots coated surface with diameter 1 mm, pitch 1.5 mm achieves the maximal heat transfer enhancement with the minimum boiling thermal resistance as low as 0.03 K/W. The comparison of three evaporator surfaces with same spot parameters but different coating materials is carried out experimentally. Ni-PTFE coated surface with immersion method performs the optimal performance of the thermosyphon.
- Fluids Engineering Division
A Loop Thermosyphon With Hydrophobic Spots Evaporator Surface
- Views Icon Views
- Share Icon Share
- Search Site
He, H, Shen, B, Hidaka, S, Takahashi, K, & Takata, Y. "A Loop Thermosyphon With Hydrophobic Spots Evaporator Surface." Proceedings of the ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels. ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels. Dubrovnik, Croatia. June 10–13, 2018. V001T02A002. ASME. https://doi.org/10.1115/ICNMM2018-7623
Download citation file: