Influence of MWCNTs geometry and surface oxidation on rheological and thermal properties of PEG nanofluids (CROSBI ID 315603)
Prilog u časopisu | izvorni znanstveni rad | međunarodna recenzija
Podaci o odgovornosti
Rebrović, Lucija ; Jukić, Ante ; Faraguna, Fabio
engleski
Influence of MWCNTs geometry and surface oxidation on rheological and thermal properties of PEG nanofluids
The focus of this research was on the thermal conductivity and rheological properties of poly(ethylene glycol) with a molecular mass of 200 g mol− 1 (i.e., PEG200) loaded with four different types of multi-walled carbon nanotubes (MWCNTs) in a wide concentration range up to 10 mass%. MWCNTs used differ in size (both diameter and length) and the content of COOH (oxidized) functional groups on their surface. It was found that the use of oxidized, shorter and wider MWCNTs in PEG200 results in highest enhancement in thermal conductivity by 133% for 10 mass% MWCNTs-PEG200 nanofluids. Investigation of the shear rate dependence of dynamic viscosity (η) showed that the use of MWCNTs in concentrations greater than 0.1 mass% changes the Newtonian behavior of PEG200 and results in the shear-thinning behavior. This behavior is strongly influenced by the MWCNT concentration in the nanofluid. When comparing the same nanofluid concentration, the highest degree of MWCNT agglomeration in PEG200 nanofluids was observed when long, thin and pristine MWCNTs were used. The thermal conductivity results were correlated with the most commonly used theoretical models: Maxwell, Hamilton- Crosser, Xue, and Murshed. Dynamic viscosity results were correlated with Einstein, Brinkman, and Brenner-Condiff theoretical models. The best agreement with the experimental results was obtained by the Maxwell and Einstein models, indicating the formation of sphere-like MWCNT agglomerates in each PEG200 nanofluid studied.
PEG-200; MWCNT; nanofluid; rheological properties; thermal conductivity; phase change materials
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
Podaci o izdanju
148 (4)
2023.
1351-1364
objavljeno
1388-6150
1588-2926
10.1007/s10973-022-11558-3
Povezanost rada
Interdisciplinarne tehničke znanosti, Kemijsko inženjerstvo