Flow boiling behaviors in hydrophilic and hydrophobic microchannels |
| |
Authors: | Chiwoong Choi Jeong Seob Shin Dong In YuMoo Hwan Kim |
| |
Affiliation: | a Department of Mechanical Engineering, Pohang University of Science and Technology, San 31, Hyoja Dong, Pohang 790-784, Republic of Korea b AC R&D Laboratory, LG Electronics, Gasan-dong, Geumcheon-gu, Seoul 327-23, Republic of Korea |
| |
Abstract: | Surface wettability is a critical parameter in small scale phenomena, especially two-phase flow, since the surface force becomes dominant as size decreases. In present study, experiments of water flow boiling in hydrophilic and hydrophobic rectangular microchannels were conducted to investigate the wettability effect on flow boiling in rectangular microchannels. The rectangular microchannels were fabricated with a photosensitive glass to visualize flow pattern. The hydrophilic bare photosensitive glass microchannel was chemically treated to obtain a hydrophobic microchannel. And, visualization of flow patterns was carried out. And boiling heat transfer and two-phase pressure drop was analyzed with visualization results. The boiling heat transfer coefficient in the hydrophobic rectangular microchannel was higher than that in the hydrophilic rectangular microchannel, which was highly related with nucleation site density and liquid film motion. And the pressure drop in the hydrophobic rectangular microchannel was higher than that in the hydrophilic rectangular microchannel, which was highly related with unstable motions of bubble and liquid film. Finally, we find out the wettability is important parameter on the flow pattern, which were highly related with two-phase heat and mass transfer. |
| |
Keywords: | Flow boiling Microchannel Wettability Heat transfer Pressure drop |
本文献已被 ScienceDirect 等数据库收录! |
|