Browse > Article

A Study on the Thermal Conductivity of Carbon-Nanotube Nanofluids  

Kim, Bong-Hun (Automotive, Industrial and Mechanical Eng. Dept., Daegu University)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.19, no.3, 2007 , pp. 275-283 More about this Journal
Abstract
An experimental study was conducted to investigate the effect of the morphology of CNT (Carbon Nanotube) on the thermal conductivity of suspensions. The effective thermal conductivities of the samples were measured using a steady-state cut bar apparatus method. Enhancements based on the thermal conductivity of the base fluid are presented as functions of both the volume fraction and the temperature. Although functionalized SWNT (Single-Walled Carbon Nanotube) produced more stable and homogeneous suspensions, the addition of small amounts of surfactant to suspensions of 'as produced' SWNT demonstrated a greater increase in effective thermal conductivity than functionalized SWNT alone. The effective thermal conductivity enhancement corresponding to 1.0% by volume approached 10%, which was observed to be lower than expected, but more than twice the values, 3.5%, obtained for similar tests conducted using aluminum oxide suspensions. However, for suspensions of MWNT (Multi-Walled Carbon Nanotube), the degree of enhancement was measured to be approximately 37%. It was postulated that the effect of clustering, resulting from the multiple heat-flow passages constituted by interconnecting neighboring CNT clusters, played an important role in significant enhancement of effective thermal conductivity.
Keywords
Caron nanotube; Nanofluid; Effective thermal conductivity; Clustering; Aspect ratio;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Berber, S., Kwon, Y. and Tomanek, D., 2000, Unusually high thermal conductivity of carbon nanotubes, Physical Review Letters, Vol. 84, No. 20, pp. 4613-4616   DOI   ScienceOn
2 Assael, M. J. Chen, C. F., Metaxa, I. and Wakeham, W. A., 2004, Thermal conductivity of suspensions of carbon nanotubes in water, International Journal of Thermophysics, Vol. 25, No.4, pp. 971-984   DOI
3 Challoner, A. R. and Powell, R. W., 1956, Thermal conductivities of liquids: New determinations for seven liquids and appraisal of existing values, Proceedings of the Royal Society of London, Series A, Vol. 238, No. 1212, pp.90-106
4 Applied Nanotechnologies Inc., Technical Bro chure:http//www.applied-nanotech.com/cntproperties.htm
5 Choi, S. U. S., Zhang, Z. G., Yu, W., Lockwood, F. E. and Grulke, E. A., 2001, Anomalous thermal conductivity enhancement in nano-tube suspensions, Applied Physics Letters, Vol. 79, No. 14, pp.2252-2254   DOI   ScienceOn
6 Incropera, F. P. and Dewitt, D. P., 2002, Fundamentals of heat and mass transfer, Jhon Wiley and Sons, New York
7 Maxwell, J. C., 1904, Electricity and Magnetism, Part II, 3rd ed., Clarendon, Oxford, p. 440
8 American Institute of Physics Handbook, 1972, Section 4, McGraw-Hill, 3rd edition
9 Lee, S., Choi, S. U. S., Li, S., and Eastman, J. A., 1999, Measuring thermal conductivity of fluids containing oxide nanoparticles, Transaction of ASME, Journal of Heat Transfer, Vol. 121, pp.280-289   DOI
10 Wang, X., Xu., X. and Choi, U.S., 1999, Thermal conductivity of nanoparticle-fluid mixture, Journal of Thermophysics and Heat Transfer, Vol. 13, No.4, pp.474-480   DOI
11 Wen, D. S. and Ding, Y. L., 2004, Effective thermal conductivity of aqueous suspensions of carbon nanotubes (carbon nanotube nanofluids), Journal of Thermophysics and Heat Transfer, Vol. 18, No.4, pp. 481-485   DOI   ScienceOn
12 Xie, H., Lee, H., Youn, W. and Choi, M., 2003, Nanofluids containing multiwalled carbon nanotubes and their enhanced thermal conductivities, Journal of Applied Physics, Vol. 94, No.8, pp.4967-4971   DOI   ScienceOn
13 Das, S. K., Putra, N., Thiesen, P. and Roetzel, W., 2003, Temperature dependence of thermal conductivity enhancement for nanofluids, Journal of Heat Transfer, Vol. 125, pp. 567-574   DOI   ScienceOn
14 Thomsen, C., 2003, Raman scattering in carbon nanotubes, Proceedings of SPIE, Vol. 5219, Nanotubes and Nanowires, Lakhtakia, A. and Maksimenko, S. (ed), Bellingham, WA, pp.45-50
15 Tohji, K., Takahashi, H., Shinoda, Y. and Shimizu, N., 1996, Purifying single-walled nanotubes, Nature, Vol. 383, p. 679   DOI   ScienceOn
16 Zhang, J., Zou, H., Qing, Q., Yang, Y., Li, Q., Liu, Z., Guo, X. and Du, Z., 2003, Effect of chemical oxidation on the structure of single-walled carbon nanotubes, Journal of Physical Chemistry B, Vol. 107, pp. 3712-3718   DOI   ScienceOn