Heat transfer enhancement with actuation of magnetic nanoparticles suspended in a base fluid

Abstract

Due to copyright restrictions, the access to the full text of this article is only available via subscription.In this study, we have experimentally demonstrated that heat transfer can be substantially increased by actuating magnetic nanoparticles inside a nanofluid. In order to materialize this, we have utilized a miniature heat transfer enhancement system based on the actuation of magnetic nanoparticles dispersed in a base fluid (water). This compact system consists of a pool filled with a nanofluid containing ferromagneticnanoparticles, a heater, and two magnetic stirrers. The ferromagnetic particles within the pool were actuated with the magnetic stirrers. Single-phase heat transfer characteristics of the system were investigated at various fixed heat fluxes and were compared to those of stationary nanofluid (without magnetic stirring). The heat transfer enhancement realized by the circulation of ferromagneticnanoparticles dispersed in a nanofluid was studied using the experimental setup. The temperatures were recorded from the readings of thin thermocouples, which were integrated to the heater surface. The surface temperatures were monitored against the input heat flux and data were processed to compare the heat transfer results of the configuration with magnetic stirrers to the heat transfer of the configuration without the magnetic stirrers.TÜB

Demir Bazlı Nano-Sıvının Tek-Faz ve Havuz Kaynama Isı Transferi Şartlarında Ekserji Analizi

“…Şekil 3 (a-b)'de manyetik kuvvetin olduğu ve olmadığı durumlardaki farklı konsantrasyonlardaki Fe3O4 nano-sıvısının ekserji yıkım oranları karşılaştırılmıştır. [24]. Nano-parçacık konsantrasyon etkisi çalışmaları daha çok havuz kaynama ya da akış kaynama şartlarında yapılmış olup tek-faz ısı transferi şartlarındaki etkisinden bahsedilmemiştir.…”

“…Literatürde kümelenme ve çökelme sorunlarını aşmak için manyetik kuvvetle hareketlendirilen nano-sıvılar kullanılmıştır [20][21][22][23][24]. Şeşen vd.…”

“…Başka bir çalışmada ise Şeşen vd. [24] ferro-manyetik nano-parçacıkların deneysel olarak tek-fazlı ısı transferini özelliklerini inceledi. Çalışmanın sonunda ortalama ısı transferi katsayısının manyetik kuvvet altında % 37.5 iyileşme gösterdiği ve sadece ekstradan 5 W pompa gücü ile bunun sağlandığını bildirdiler.…”

Effect of magnetic field-dependent thermal conductivity on natural convection of magnetic nanofluid inside a square enclosure

“…Numerous studies have been carried out on passive and active heat transfer systems equipped with nanofluids to increase their efficiencies (Huminic et al, 2011;Morega et al, 2012;Rashidi et al, 2018bRashidi et al, , 2018aEl Bécaye Maïga et al, 2006). Because of the unique properties of nanofluid, they are being used in different applications such as fuel cells, engine cooling/vehicle thermal management, microelectronics and hybrid-powered engines (Sesen et al, 2012;Zakaria et al, 2015;Minkowycz et al, 2012). It has been found that the rheological behavior of nanofluids is very important in determining their suitability for convective heat transfer applications (Witharana et al, 2011).…”

Tuning magnetofluidic spreading in microchannels

“…ferrohydrodynamics, magnetorheology and magnetophoresis, which are relevant to a broad spectrum of applications. MMF can be useful for applications such as micromixing [3,4], actuation [5][6][7], magnetic separation [8,9], heat transfer enhancement [10,11], MEMS [12] and optofluidics [13]. MMF is also the guiding principle behind several biomedical applications involving nanocytometry-microcytometry [14,15], cell sorting [16,17], cell analysis [18,19], immobilization of enzymes [19,20], MRI [21] and magnetic fluid hyperthermia [22,23].…”