Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
High heat flux boiling and burnout as microphysical phenomena: Mounting evidence and opportunities
KTH, Skolan för teknikvetenskap (SCI), Fysik, Kärnkraftssäkerhet.
2006 (engelsk)Inngår i: Multiphase Science and Technology, ISSN 0276-1459, E-ISSN 1943-6181, Vol. 18, nr 3, s. 251-276Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In our recent works Theofanous et al., 2002a-b, we have demonstrated that burnout in pool boiling is not hydrodynamically limited, at least not in the sense that has been perceived in the past. In this paper, we discuss the opportunities created by the new understanding of mechanisms that govern the boiling crisis. This understanding is built upon a scales separation phenomenon, referring to a vapor blanket separating the liquid film on the heater surface from the chaotic, churning flow in the two-phase pool. In essence, the scales separation suggests that mechanisms of boiling crisis should be sought within the micro-hydrodynamics of the evaporating liquid microlayer rather than in the pool thermal-hydraulics. Detail analysis of surface temperature patterns obtained by infrared imaging at high heat fluxes points to a nearly static picture of boiling heat transfer, with intense cooling at locations which were nucleation sites activated at lower heat fluxes. Furthermore, we show that control of the surface and coolant chemistry offers the potential to enhance resistance to burnout and achieve critical heat fluxes (CHF) exceeding those defined by the so-called hydrodynamic limit. Our more recent experiments show an improved resilience of the heater to burnout when a high-solubility salt or nanoparticles are added to the coolant (water). We explain the observed phenomenon through the increase in disjoining pressure at the meniscus contact line that promotes liquid spreading towards the dry area. It is noteworthy that the scales separation phenomenon provides a basis to suggest that mechanisms of enhancement to burnout in pool boiling are also active, even to a larger extent, in spray cooling and flow boiling.

sted, utgiver, år, opplag, sider
2006. Vol. 18, nr 3, s. 251-276
Emneord [en]
Boiling liquids, Heat flux, Heat transfer, Infrared imaging, Nucleation, Turbulent flow, Critical heat fluxes (CHF), Flow boiling, Scales separation phenomenon, Spray cooling, Hydrodynamics
HSV kategori
Identifikatorer
URN: urn:nbn:se:kth:diva-155982DOI: 10.1615/MultScienTechn.v18.i3.30Scopus ID: 2-s2.0-33749023903OAI: oai:DiVA.org:kth-155982DiVA, id: diva2:765905
Merknad

QC 20141125

Tilgjengelig fra: 2014-11-25 Laget: 2014-11-17 Sist oppdatert: 2022-06-23bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekstScopus

Søk i DiVA

Av forfatter/redaktør
Dinh, Truc Nam
Av organisasjonen
I samme tidsskrift
Multiphase Science and Technology

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 80 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf