Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Effect of Al2O3 Nanolubricant on R134a Pool Boiling Heat Transfer with Extensive Measurement and Analysis Details

Published

Author(s)

Mark A. Kedzierski

Abstract

This paper quantifies the influence of Al2O3 nanoparticles on the pool boiling performance of R134a/polyolester mixtures on a roughened, horizontal, flat surface. Nanofluids are liquids that contain dispersed nano-size particles. A lubricant based nanofluid (nanolubricant) was made by suspending 20 nm diameter Al2O3 particles in a synthetic ester to roughly a 1.6 % volume fraction. The nanoparticles enhanced the boiling heat transfer relative to that for R134a/polyolester mixtures without nanoparticles for the three lubricant mass fractions that were tested. The enhancement occurred for the lowest heat fluxes, which gives the opportunity for designing chillers for lower approach temperatures. For the 0.5 % nanolubricant mass fraction, the nanoparticles caused a heat transfer enhancement relative to the heat transfer of pure R134a/polyolester (99.5/0.5) as large as 400 % for the lowest tested heat flux. The average heat flux improvement for heat fluxes less than 40 kW/m2 was approximately 105 %, 49 %, and 155 % for the 0.5 %, the 1 %, and the 2 % mass fractions, respectively. The heat flux enhancement for all of the mixtures increased with respect to decreasing heat flux. Due to the good quality of the nanolubricant suspension, the performance of the (99.5/0.5), and the (98/2) nanolubricant mixtures was stable over time.
Citation
Technical Note (NIST TN) - 1663
Report Number
1663

Keywords

additives, boiling, Al2O3, enhanced heat transfer, nanotechnology, refrigerants, refrigerant/lubricant mixtures

Citation

Kedzierski, M. (2010), Effect of Al2O3 Nanolubricant on R134a Pool Boiling Heat Transfer with Extensive Measurement and Analysis Details, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=903745 (Accessed June 17, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created May 5, 2010, Updated February 19, 2017