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
Single phase laminar convective heat transfer of nanofluids in a micro-tube
KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
2011 (English)Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
Abstract [en]

Nanofluids are homogeneous mixture of dispersed solid particles in base fluids. These solid particles are usually smaller than 100nm. Suspended nanoparticles modify the properties of based fluids. It is claimed, in some literature, for nanofluids to have greater than expected heat transfer performance. Due to this, nanofluids have gained great attention from both research and development and industries active in cooling systems.

This thesis reports several measurements of convective heat transfer coefficient in a horizontal open micro-tube test section under laminar flow regime. The test section has an inner diameter of 0.5mm made of stainless steel and it has a length of 30cm. Two different test sections have been built. The first one has 13 thermocouples attached on the wall and the second one has 10. These thermocouples are used to measure the wall temperature distribution along the tube. In addition, two more thermocouples are used inside the micro-tube, at the inlet and outlet, to measure the bulk temperature of the nanofluids. A syringe pump is used for injecting the nanofluids through the micro-tube. A DC power supply provides constant heat flux along the test section and a differential pressure transducer measures the pressure drop of the test section.

Aqueous based Al2O3 (9 wt %), ZrO2 (9 wt %), TiO2(9 wt %), CeO2 (9wt %), CNT (0.15 wt %), and diamond (1 wt %) have been tested in this thesis. Local Shah’s correlation predicts very well the behaviour of these nanofluids. The results are compared with water in six different ways: heat transfer forconstant Reynolds numbers, volume and mass flow rates, pressure drops andpumping powers. Enhancement in heat transfer is recognisable only in thegraphs of Nu numbers for constant Reynolds numbers. This can be attributed to the higher viscosity for nanofluids. Moreover, friction factor for constant Reynolds numbers has been compared. All the nanofluids with the exception of Al2O3 and diamond suit quite well with Darcy-Weisbach correlation.

Place, publisher, year, edition, pages
2011. , 121 p.
Keyword [en]
Nanofluids, convective, micro-tube, laminar
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:kth:diva-80237OAI: oai:DiVA.org:kth-80237DiVA: diva2:496135
Subject / course
Heat Transfer
Educational program
Master of Science - Industrial Engineering and Management
Uppsok
Technology
Supervisors
Examiners
Available from: 2012-02-10 Created: 2012-02-09 Last updated: 2012-02-10Bibliographically approved

Open Access in DiVA

fulltext(11691 kB)1199 downloads
File information
File name FULLTEXT01.pdfFile size 11691 kBChecksum SHA-512
9f6466b953959c079bfa61a51e79f6cec980fc9c0f3cac465b92a7ab4684be10179ab1bc7ec6a2565c62667bc7660d60b59c5eb55f6a2b2f4329ddecfbd3ae9e
Type fulltextMimetype application/pdf

By organisation
Energy Technology
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 1199 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

urn-nbn

Altmetric score

urn-nbn
Total: 282 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