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undergraduate thesis
Toplinsko i reološko ponašanje nanofluida
Zagreb: University of Zagreb, Faculty of Chemical Engineering and Technology, 2015. urn:nbn:hr:149:393092
Ždrakić, Marija
University of Zagreb
Faculty of Chemical Engineering and Technology

Institutional repository: Repository of Faculty of Chemical Engineering and Technology University of Zagreb

Cite this document

Ždrakić, M. (2015). Toplinsko i reološko ponašanje nanofluida (Undergraduate thesis). Zagreb: University of Zagreb, Faculty of Chemical Engineering and Technology. Retrieved from https://urn.nsk.hr/urn:nbn:hr:149:393092

Ždrakić, Marija. "Toplinsko i reološko ponašanje nanofluida." Undergraduate thesis, University of Zagreb, Faculty of Chemical Engineering and Technology, 2015. https://urn.nsk.hr/urn:nbn:hr:149:393092

Ždrakić, Marija. "Toplinsko i reološko ponašanje nanofluida." Undergraduate thesis, University of Zagreb, Faculty of Chemical Engineering and Technology, 2015. https://urn.nsk.hr/urn:nbn:hr:149:393092

Ždrakić, M. (2015). 'Toplinsko i reološko ponašanje nanofluida', Undergraduate thesis, University of Zagreb, Faculty of Chemical Engineering and Technology, accessed 28 March 2025, https://urn.nsk.hr/urn:nbn:hr:149:393092

Ždrakić M. Toplinsko i reološko ponašanje nanofluida [Undergraduate thesis]. Zagreb: University of Zagreb, Faculty of Chemical Engineering and Technology; 2015 [cited 2025 March 28] Available at: https://urn.nsk.hr/urn:nbn:hr:149:393092

M. Ždrakić, "Toplinsko i reološko ponašanje nanofluida", Undergraduate thesis, University of Zagreb, Faculty of Chemical Engineering and Technology, Zagreb, 2015. Available at: https://urn.nsk.hr/urn:nbn:hr:149:393092

Metadata
TitleToplinsko i reološko ponašanje nanofluida
Title (english)Thermal and rheological behavior of nanofluids
AuthorMarija Ždrakić
MentorJasna Prlić Kardum (mentor)
Committee memberJasna Prlić Kardum (predsjednik povjerenstva)
Committee memberAleksandra Sander (član povjerenstva)
Committee memberVanja Kosar (član povjerenstva)
GranterUniversity of Zagreb
Faculty of Chemical Engineering and Technology
Zagreb
Defense date and country2015-09-18, Croatia
Scientific / art field,
discipline and subdiscipline		TECHNICAL SCIENCES
Chemical Engineering
Mechanical, Thermal and Separation Processes
Abstract
U ovom radu ispitivana je stabilnost i termo-fizikalna svojstva nanofluida sa i bez aditiva. Za pripravu suspenzija korištene su nanoĉestice Al2O3 koje su dispergirane u demineraliziranoj vodi u 0.5, 1.0, 1.5 vol %. U suspenziju koja sadrži 0.5 vol % Al2O3 dodani su razliĉiti aditivi (polivinil alkohol (PVA), polivinilpirolidon (PVP), arapska guma (AG), heksadeciltrimetilamonijev bromid (CTAB) i natrijev dodecil-sulfat (SDS)) u razliĉitim masenim omjerima. Pripravljenim nanosuspenzijama... More izmjerena je gustoća, viskoznost i koeficijent toplinske vodljivosti. Da bi se definirala stabilnost nanosuspenzija, praćena je promjena pH vrijednosti i toplinske vodljivosti suspenzija s vremenom. Poboljšanje stabilnosti postiže se povećanjem volumnog udjela Al2O3, te dodatkom aditiva (s izuzetkom SDS-a). Iako su nanofluidi s dodanim aditivima stabilniji od nanosuspenzija bez aditiva, njihovom upotrebom se smanjuje toplinska vodljivost, povećava gustoća i viskoznost. Korištenjem površinski aktivnih tvari mijenjaju se reološke karakteristike nanosuspenzija iz newtonskih u nenewtonske fluide. Najbolja stabilizacijska svojstva pokazao je PVA ĉijom upotrebom se ne mijenja reološko ponašanje nanosuspenzije, a viskoznost i gustoća mu se neznatno povećavaju u odnosu na nanofluid iste koncentracije bez aditiva. Toplinska vodljivost nije smanjena, a stabilnost je zadovoljavajuća. Less
Abstract (english)
In these work stability and thermo- physical properties of nanofluids with and without additives were examined. Nanofluids were prepared by disperzion of Al2O3 nanoparticles in demineralized water in 0.5; 1.0; 1.5 vol%. In 0.5 vol% suspension different additives in different volume portions were added (Polyvinyl alcohol (PVA), Polyvinylpyrrolidone (PVP), Gum arabic (AG), Hexadecyltrimethylammonium bromide (CTAB) and Sodium dodecyl sulfate (SDS). Density, viscosity and thermal... More conductivity of prepared nanosuspensions were determined. To define the stability of the nanosuspensions, the change in the pH values and thermal conductivity of the suspensions was measured within a time period. The improvement in the stability was achieved through the increase of the mass ratio of Al203, and through the addition of the additives (not including SDS). Although the nanofluids with the additives proved more stable than the ones without the additives, the use of the additives decreased thermal conductivity, and increased the density and viscosity. The use of surfactants changed rheological characteristics of the nanosuspensions from Newtonian fluids into non-Newtonian fluids. PVA was shown to have the best stabilising properties. It’s use didn’t change the rheological characteristics of the nanosuspension, and viscosity and density were only slightly increased in comparison to the nanofluid of the same concentration but without the additives. Thermal conductivity was not decreased, while the stability was satisfactory. Less
Keywords
Keywords (english)
Languagecroatian
URN:NBNurn:nbn:hr:149:393092
Study programmeTitle: Environmental Engineering - Undergraduate study
Study programme type: university
Study level: undergraduate
Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva)
Type of resourceText
File originBorn digital
Access conditionsOpen access
Terms of useLicence In copyright icon
Created on2016-12-02 14:05:31
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