[article]
Titre : |
Flow boiling visualization of R-134a in a vertical channel of small diameter |
Type de document : |
texte imprimé |
Auteurs : |
Claudi Martín-Callizo, Auteur ; Björn Palm, Auteur ; Wahib Owhaib, Auteur |
Article en page(s) : |
pp. [031503-1/8] |
Note générale : |
Physique |
Langues : |
Anglais (eng) |
Mots-clés : |
Flow boiling Two-phase patterns Microchannel Refrigerant R-134a |
Index. décimale : |
536 Chaleur. Thermodynamique |
Résumé : |
The present work reports on flow boiling visualization of refrigerant R-134a in a vertical circular channel with an internal diameter of 1.33 mm and 235 mm in heated length. A quartz tube with a homogeneous Indium Tin Oxide coating is used to allow heating and simultaneous visualization. Flow patterns have been observed along the heated length with the aid of high-speed complementary metal oxide semiconductor (CMOS) digital camera. From the flow boiling visualization, seven distinct two-phase flow patterns have been observed: isolated bubbly flow, confined bubbly flow, slug flow, churn flow, slug-annular flow, annular flow, and mist flow. Two-phase flow pattern observations are presented in the form of flow pattern maps. The effects of the saturation temperature and the inlet subcooling degree on the two-phase flow pattern transitions are elucidated. Finally, the experimental flow pattern map is compared with models developed for conventional sizes as well as to a microscale map for air-water mixtures available in literature, showing a large discrepancy.
|
DEWEY : |
536 |
ISSN : |
0022-1481 |
En ligne : |
http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] |
in Journal of heat transfer > Vol. 132 N° 3 (Mars 2010) . - pp. [031503-1/8]
[article] Flow boiling visualization of R-134a in a vertical channel of small diameter [texte imprimé] / Claudi Martín-Callizo, Auteur ; Björn Palm, Auteur ; Wahib Owhaib, Auteur . - pp. [031503-1/8]. Physique Langues : Anglais ( eng) in Journal of heat transfer > Vol. 132 N° 3 (Mars 2010) . - pp. [031503-1/8]
Mots-clés : |
Flow boiling Two-phase patterns Microchannel Refrigerant R-134a |
Index. décimale : |
536 Chaleur. Thermodynamique |
Résumé : |
The present work reports on flow boiling visualization of refrigerant R-134a in a vertical circular channel with an internal diameter of 1.33 mm and 235 mm in heated length. A quartz tube with a homogeneous Indium Tin Oxide coating is used to allow heating and simultaneous visualization. Flow patterns have been observed along the heated length with the aid of high-speed complementary metal oxide semiconductor (CMOS) digital camera. From the flow boiling visualization, seven distinct two-phase flow patterns have been observed: isolated bubbly flow, confined bubbly flow, slug flow, churn flow, slug-annular flow, annular flow, and mist flow. Two-phase flow pattern observations are presented in the form of flow pattern maps. The effects of the saturation temperature and the inlet subcooling degree on the two-phase flow pattern transitions are elucidated. Finally, the experimental flow pattern map is compared with models developed for conventional sizes as well as to a microscale map for air-water mixtures available in literature, showing a large discrepancy.
|
DEWEY : |
536 |
ISSN : |
0022-1481 |
En ligne : |
http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] |
|