On the pulse boiling frequency in thermosyphons
- Harbin Inst. of Tech. (China)
- Concordia Univ., Montreal, Quebec (Canada)
The unsteady periodic boiling phenomenon, pulse boiling, appearing in the evaporator of thermosyphons has been mentioned and investigated by many researchers. The heat transfer coefficient in evaporators was predicted according to different considerations of flow patterns. For instance, Shiraishi et al. proposed a method based on a combination flow pattern: the nucleate boiling in a liquid pool and the evaporation from a falling condensate film. Liu et al. only considered a pure pulse boiling flow pattern, and Xin et al. focused on the flow pattern of the continuous boiling process without pulse phenomenon. Besides, the forming conditions of pulse boiling were also described differently. Xin et al. also reported that pulse boiling cannot occur in a carbon-steel/water heat pipe; Ma et al., however, observed this phenomenon in a carbon-steel/water thermosyphon. Nearly all researchers mentioned that this phenomenon indeed exists in glass/water thermosyphons. Although the influential factors have been discussed qualitatively, the quantitative analysis has yet to be conducted. This study focuses on the pulse boiling frequency as a criterion for the determination of flow patterns, and attempts are made to predict the frequency both experimentally and theoretically.
- OSTI ID:
- 5097002
- Journal Information:
- Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States), Vol. 114:1; ISSN 0022-1481
- Country of Publication:
- United States
- Language:
- English
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