Due to copyright restrictions, the access to the full text of this article is only available via subscription.Nanofluids offer a potential breakthrough as next-generation heat transfer fluids since they offer exciting new possibilities to enhance heat transfer performance compared to pure liquids. A major drawback for using nanofluids in practical applications is difficulty in maintaining their stability due to deposition on surfaces. In this study, we propose and experimentally investigate a magnetic actuation scheme to avoid this deposition. Two-phase heat transfer characteristics of the designed system have been experimentally investigated with magnetic actuation and compared to the results without magnetic actuation. Two phase average heat transfer enhancement observed with the suggested system was 17%. The average single phase enhancement is found as 29% with magnetic actuation. It was observed that magnetically actuated nanoparticles neither form any clusters nor precipitate after the experiments.TÜBA ; Kadir Has Outstanding Young Investigator Support Program ; TÜBİTAK ; Sabanci Universit

No 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