(An) application of nano-fluids to enhance CHF in in-vessel retention system = 나노 유체를 이용한 임계열유속 증진과 원자로 외벽냉각 성능 향상에 관한 연구

Cited 0 time in webofscience Cited 0 time in scopus
  • Hit : 315
  • Download : 0
In-vessel retention (IVR) by external vessel flooding to maintain the molten core in reactor vessel by cooling the outer of it is one of the accident management strategies currently being employed in some advanced water reactors. However, the ability of the reactor vessel to transfer heat into coolant beneath the vessel is limited by the occurrence of critical heat flux (CHF) at its outer surface. Enhancing CHF at the outer surface of the reactor vessel allows a higher thermal margin and a significant enhancement of IVR capability. Higher CHF can be achieved by using either an advance coolant and/or an engineered fuel cladding surface. Nano-fluids, colloidal dispersions of nano-size particles in base fluids, have been of interest for the last decade as advanced coolant for heat transfer systems, including nuclear reactors. One of the most interesting properties of nano-fluids is to enhance CHF over that of the base fluids, which has been obtained in many previous works. This opens a possibility for using nano-fluids to enhance the IVR capabilities of Advanced Light Water Reactor (ALWR) systems. In this study, pool boiling CHF behavior on a small plate at varying inclination angle of the heated surface under atmospheric pressure was examined. Three nano-fluids with high suspension stability were selected by the Zeta Potential method to investigate the effects of each nano-fluid on pool boiling CHF, which were 0.05% $Al_2O_3$, 0.05% CNT + 10% $H_3BO_3$, 0.05% $Al_2O_3$ + 0.05% CNT. CHF increased as the heated surface was inclined from downward facing to vertical position. Nano-fluids enhanced CHF significantly in comparison with pure water. Among the three selected fluids, combination of $Al_2O_3$ + CNT nano-particles showed the highest CHF enhancement with the maximum of 122% at downward facing position, while $Al_2O_3$ nano-fluid exhibited the lowest CHF enhancement. The underlying mechanism of CHF enhancement in nano-fluids was investigated. Surface morpho...
Advisors
Chang, Soon-Heungresearcher장순흥researcher
Description
한국과학기술원 : 원자력및양자공학과,
Publisher
한국과학기술원
Issue Date
2009
Identifier
327313/325007  / 020083971
Language
eng
Description

학위논문(석사) - 한국과학기술원 : 원자력및양자공학과, 2009. 8., [ vii, 75 p. ]

Keywords

Critical heat flux; Nano-fluid; IVR; 임계 열유속; 나노 유체; 노심 용융물 억류

URI
http://hdl.handle.net/10203/49559
Link
http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=327313&flag=dissertation
Appears in Collection
NE-Theses_Master(석사논문)
Files in This Item
There are no files associated with this item.

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0