Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Experimental investigation of dryout of propane in uniformly heated single vertical mini-channels
KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.ORCID iD: 0000-0002-9902-2087
KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
2012 (English)In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 37, 121-129 p.Article in journal (Refereed) Published
Abstract [en]

This article presents dryout results of propane in single vertical circular minichannels made of stainless steel with internal diameters of 1.70 mm and 1.224 mm. The heat flux is increased in steps up to occurrence of dryout. The effects of different parameters such as mass flux, saturation temperature, vapour quality and internal diameter on the dryout are investigated. The results show that the dryout heat flux increases with the increase in mass velocity, with the decrease of vapour quality and with the increase of internal diameter. Almost no effect of saturation temperature on dryout heat flux is observed. Generalised CHF correlations developed for macro and micro scale from the literature are also compared with the experimental results.

Place, publisher, year, edition, pages
2012. Vol. 37, 121-129 p.
Keyword [en]
Minichannels, Dryout, Propane, Experimental study, CHF
National Category
Energy Engineering
Identifiers
URN: urn:nbn:se:kth:diva-80605DOI: 10.1016/j.expthermflusci.2011.10.012ISI: 000301013900015Scopus ID: 2-s2.0-84855197122OAI: oai:DiVA.org:kth-80605DiVA: diva2:496524
Note
QC 20120210Available from: 2012-02-10 Created: 2012-02-10 Last updated: 2017-12-07Bibliographically approved
In thesis
1. Flow boiling of ammonia and propane in mini channels
Open this publication in new window or tab >>Flow boiling of ammonia and propane in mini channels
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The environmental concerns in recent times have grown especially after signing Montreal protocol. In the last ten years, researchers have focussed mainly on understanding the boiling and condensation phenomena of HFC refrigerants in minichannels. As global warming concerns are growing day by day, due to high global warming potential, HFCs are not the ultimate option. In the near future, HFCs will probably be replaced by environmentally friendly refrigerants. Therefore, to find the potential replacements of HFCs and also to get a deeper understanding of the boiling phenomena in minichannels, more and more fluids having low GWP (Global Warming Potential) and ODP (Ozone Depletion Potential) should be tested. Recent efforts to protect the environment have led to a growing interest for natural refrigerants. However in the literature, flow boiling data of natural refrigerants in minichannels are scarce.

To meet the environmental concerns and to understand the behaviour of natural refrigerants in minichannels and the performance compared to HFCs, flow boiling experiments in single circular vertical minichannels of internal diameters of 1.70 and 1.224 mm were performed using ammonia and propane as working fluids.

Flow boiling heat transfer results of ammonia and propane with 1.70 mm channel showed that the heat transfer coefficient was a function of heat flux and the effect of mass flux was insignificant. The heat transfer coefficient of ammonia in 1.224 mm was dependent on heat flux at low vapour qualities then a clear dependence of the heat transfer coefficient on the mass flux was observed at higher vapour qualities. The heat transfer results of ammonia and propane were compared with well known correlations and among them Cooper (1989) correlation in case of ammonia and Liu and Winterton (1991) and Cooper (1984) pool boiling correlations in case of propane best predicted the experimental heat transfer data.

Results of the two phase pressure drop studies of ammonia and propane showed that the two phase pressure drop increased with the increase of mass flux, with the increase of heat flux and with the decrease of saturation temperature. The comparison of the two phase pressure drop experimental data with well known predicting models showed that none of the correlations predicted the ammonia data well and that Müller Steinhagen and Heck (1986) was well in agreement with the propane data.

Dryout of propane in 1.70 mm and 1.224 mm internal diameter channels was also investigated. Dryout heat flux was observed to increase with the increase of mass flux, with the decrease of vapour quality and with the increase of internal diameter. The effect of saturation temperature on the dryout heat flux was insignificant. The experimental dryout data were compared with macro and micro scale correlations and among them Bowring (1972) and Callizo et al. (2010a) gave best predictions.

The heat transfer and pressure drop results of ammonia and propane and dryout results of propane were compared with R134a data taken on the same test rig by Owhaib (2007) and Ali (2010). The comparison of heat transfer showed that the heat transfer coefficient was a function of heat flux and the effect of mass flux was insignificant in all tested conditions except ammonia in 1.224 mm tube where the heat transfer coefficient was dependent on heat flux at lower vapour qualities and a clear dependence of mass flux was observed at higher vapour qualities. The heat transfer data of ammonia, propane and R134a were compared with correlations and among them Cooper (1989) correlation gave best predictions. The comparison of pressure drop results showed that the two phase pressure drop of all fluids was increased with the increase of mass flux, with the increase of heat flux and with the decrease of saturation temperature. At equal heat flux and mass flux, the two phase pressure drop of ammonia was increased with the decrease of internal diameter but the diametric effects of R134a were unclear. Müller Steinhagen and Heck (1986) and Zhang and Webb (2001) best predicted the experimental data of two phase pressure drop of ammonia, propane and R134a among the correlations considered for comparison. The dryout data of propane were also compared with dryout data of R134a and it was observed that the dryout heat flux of propane and R134a increased with the increase of mass flux, with the decrease of vapour quality and with the increase of internal diameter. The effect of saturation temperature on the dryout heat flux of propane and R134a was insignificant. The correlation of Bowring (1972) for conventional channels and the microscale correlation of Callizo et al. (2010a) were among the correlations which gave best predictions of experimental data of dryout.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2012. viii, 107 p.
Series
Trita-REFR, ISSN 1102-0245 ; 12:01
Keyword
Flow Boiling, Mini channels, Global Warming Potential, Ammonia, Propane, R134a, HFC, Two-phase, Heat Transfer, Pressure Drop, Dry out.
National Category
Engineering and Technology
Identifiers
urn:nbn:se:kth:diva-80331 (URN)978-91-7501-264-3 (ISBN)
Public defence
2012-02-27, Sal F3, Lindstedtsvägen 26, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20120210Available from: 2012-02-10 Created: 2012-02-09 Last updated: 2012-02-10Bibliographically approved

Open Access in DiVA

fulltext(1894 kB)598 downloads
File information
File name FULLTEXT01.pdfFile size 1894 kBChecksum SHA-512
2a82bdc79a673bcabd1eb9d4290d7d9875904a312b79ecd656172bce992faa29ad8866760e5944b7e7f0ddfcb5baf405b6e14effbb39d231a749a4865154a1c7
Type fulltextMimetype application/pdf

Other links

Publisher's full textScopusScience direct

Search in DiVA

By author/editor
Maqbool, Muhammad HamayunPalm, BjörnKhodabandeh, Rahmatollah
By organisation
Applied Thermodynamics and Refrigeration
In the same journal
Experimental Thermal and Fluid Science
Energy Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 598 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 85 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf