Su Bazlı Nanoakışkanların Hazırlanmasında Kullanılan Yeni Yüzey Modifiye Fe3O4 Nanopartiküllerinin Uzun Vadeli Kararlılıklarının İncelenmesi

Abstract

Nanofluids are produced by suspending different solid nano-size materials (metal and nonmetal) in a base liquid and are often used in energy systems to increase thermal performance and heat transfer rate. The main problem observed in nanofluids used in heat transfer applications is their instability. Researchers have developed and proposed some solutions to obtain stable nanofluids. One of the most important solutions, is the nanoparticles surface modification method. In this work, Fe3O4 nanoparticles were subjected to chemical processes and their surfaces were modified. Three different modified nanoparticles were synthesized, which are Fe3O4@SiO2@Si(CH2)3-IM [Cl], Fe3O4@Si(CH2)3-IM [Cl], and Fe3O4@SiO2&Si(CH2)3-IM [Cl] nanoparticles. The nanofluids were prepared in 0.2% Vol. fraction by using the produced particles in base fluid which was distilled water, and stability of nanofluids were observed for 3 months. Nanofluids were subjected to ultrasonication for 3.5 h to obtain homogeneous nanofluid. Not modified water-based Fe3O4 nanofluid completely collapsed in approximately 1 week. In modified nanofluids, although sedimentation occurred, it was observed that a certain amount of the particles remained suspended even after 3 months. The most important analyses in this study are Scanning Electron Microscope, X-Ray Diffraction, and Transmission Electron Microscope.

Experimental and numerical investigation of flow and thermal characteristics of aluminum block exchanger using surface-modified and recycled nanofluids

“…Moreover, all of the particles used in the preparation of nanofluids are recycled nanoparticles. In the recycling process, the base fluid was separated from the used nanofluid by evaporation (Mandev et al , 2022; Muratçobanoğlu et al , 2022).…”

“…Fe 3 O 4 nanoparticles were used in experiments because they have better thermophysical and magnetic properties (Khedkar et al , 2013; Giwa et al , 2020). The used particles were subjected to surface modification to increase their stability in the prepared nanofluid (Muratçobanoğlu et al , 2022). In addition, another critical issue for the used nanofluids was the high cost of nanoparticles.…”