Utjecaj duljine nanocijevi na svojstva nanomaziva

master's thesis

• Title (english): Influence of nanotubes length on characteristics of nanolubricants
• Author: Krešimir Stublić
• Mentor: Elvira Vidović (mentor)
• Committee member: Elvira Vidović (predsjednik povjerenstva)
• Committee member: Sanja Lučić Blagojević (član povjerenstva)
• Committee member: Domagoj Vrsaljko (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2016-09-28, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Chemical Engineering in Material Development

Abstract

Cilj ovog rada jest istraživanje utjecaja duljine nanocijevi na toplinsku vodljivost nanofluida na osnovi PAO 4 i YUBASE 4 ulja s višestjenčanim ugljikovim nanocijevima (MWCNT). Eksperimentalni dio podijeljen je u dvije faze. U prvoj fazi pripremljeni su nanofluidi s ugljikovim nanocijevima duljine 50 μm, te različitim surfaktantima (PAT). Ispitana je stabilnost pripremljenih nanofluida, s ciljem utvrđivanja najkompatibilnijih sustava. U drugoj fazi pripremljeni su nanofluidi s ugljikovim nanocijevima duljine u rasponu od 0,5 do 2 μm, te različitim surfaktantima. Također je ispitana stabilnost pripremljenih nanofluida. Najstabilniji nanofluidi iz obje faze ponovo su pripremljeni s ciljem određivanja toplinske vodljivosti. Stabilnost nanofluida ispitana je sedimentacijskim testom vizualnom i instrumentalnom metodom (UV/VIS spektrofotometrija). Vizualna metoda sastoji se od slikanja uzoraka nanofluida i analize slike. Snimljeni su UV/VIS apsorpcijski spektri uzoraka kako bi se odredila stabilnost nanofluida. Stabilnost je prikazana u obliku raspršenosti MWCNT-a u baznom fluidu. Određen je utjecaj surfaktanata na viskoznost baznih fluida, te je izmjerena toplinska vodljivost uzoraka metodom toplinskog impulsa.

Abstract (english)

The aim of this paper was to study the impact of the carbon nanotubes length on the thermal conductivity of nanofluids based on PAO 4 and YUBASE 4 oil with multiwalled carbon nanotubes (MWCNT). Experimental section was divided into two phases. In the first phase nanofluids with carbon nanotubes length of 50 μm, and different surfactants were prepared, as the aim was to explore compatibility of various surfactants with base oils oil and MWCNT. In the second phase nanofluids with carbon nanotubes length in the range from 0.5 to 2 μm, and different surfactants were prepared to explore compatibility of various surfactant and base oil combinations as well. Lastly, the most stabile nanofluids from both phases were prepared in order to test the thermal properties. Sedimentation rate was examined visually and using instrumental method in order to test the nanofluid stability. Visual method includes photographing nanofluid samples, and analysis of the photograph. UV/VIS absorption specters were measured, and the nanofluid stability was presented as a dispersion of the MWCNTs in base fluid. Effect of various surfactants on the base oil viscosity was examined, as well as thermal conductivity of prepared nanofluids.

• Keywords: nanofluidi; ugljikove nanocijevi; toplinska vodljivost
• Keywords (english): nanofluids; carbon nanotubes; thermal conductivity
• Language: croatian
• URN:NBN: urn:nbn:hr:149:658575
• Study programme: Title: Chemical Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-10-31 13:19:09