Abstract
Nanofluids are nanosize-powder suspensions that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives to ordinary cooling fluids, but the tribiological effects of nanofluids on cooling-system materials are largely unknown. The authors have developed methodology that uses jet impingement on typical cooling-system materials to test such effects. The work is presented of the authors’ research on the interactions of a typical nanofluid (2% volume of alumina nanopowders in a solution of ethylene glycol in water) which is impinged on aluminum and copper specimens for tests as long as 112 hours. The surface changes were assessed by roughness measurements and optical-microscope studies. Comparative roughness indicate that both the reference cooling fluid of ethylene glycol and water and its nanofluid with 2% alumina produce roughness changes in aluminum (even for the shortest 3-hour test), but no significant roughness differences were observed between them. No significant roughness changes were observed for copper. Microscopy observations, however, show different surface modifications in both aluminum and copper by both the nanofluid and its base fluid. The possible mechanisms of early erosion are discussed. These investigations demonstrate suitable methods for the testing of nanofluid effects on cooling system-materials.
Highlights
Introduction and Literature ReviewThe concept of nanofluid was proposed in 1995 by Choi and Eastman [1] and Choi [2] as a suspension of solid nanosize (1 to 100 nanometers) particles in a carrier liquid
This paper presents the authors’ recent work on wear and erosion effects of alumina-nanopowder-nanofluid jet-impingement on two typical cooling-system materials, aluminum and copper, for long experiments, including microscopy analysis of the impacted surfaces, and discussion of possible mechanisms of surface modification
The authors developed an instrument to employ a lowspeed jet for the testing of nanofluid interactions with typical cooling-system material surfaces
Summary
The concept of nanofluid was proposed in 1995 by Choi and Eastman [1] and Choi [2] as a suspension of solid nanosize (1 to 100 nanometers) particles in a carrier liquid. Nanofluids are promising as coolants for critical-cooling systems, as nuclear systems [4], large engine radiators, and microchips [5]. These and other potential uses of nanofluids, as applications for enhanced detergency, in the biomedical field, and as smart fluids, were discussed by Wong and De Leon [5]. Preparation of nanofluids, and nanofluid performance as transport- and electromagnetically active-media and as media for chemical reactions have been recently reviewed by Taylor et al [6]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
