DOI QR코드

DOI QR Code

An Experimental Study on Pressure Drop and Heat Transfer Coefficient of Laminar Ag Nanofluid Flow in Mini-Tubes

은 나노유체의 미세관내 층류 유동의 압력강하 및 열전달계수에 관한 실험적 연구

  • Kwon, Jeong-Tae (Department of Mechanical Engineering, Hoseo University) ;
  • Nahm, Taek-Hun (Department of Mechanical Engineering, Hoseo University) ;
  • Kim, Tae-Wan (Department of Mechanical Engineering, Hoseo University) ;
  • Kwon, Young-Chul (Department of Mechanical Engineering, Sunmoon University)
  • Published : 2009.12.31

Abstract

This study presents the heat transfer and pressure drop characteristics of Ag nanofluid in mini-tubes(outer diameters of 1/8inch, 3/16inch). Experiments were performed for Reynolds numbers ranged from 500 to 2,500 and nanofluid concentrations of 0.1 and 0.3vol.%. The pressure drop of nanofluid flow increased by max. 21% compared with that of distilled water. The heat transfer coefficients of the nanofluid of 0.1 vol.% enhanced 3~42% for 1/8inch tube, and 3~69% for 3/16inch tube. Also, the heat transfer coefficients of the nanofluid of 0.3 vol.% enhanced 35~65% for 1/8inch tube, and 62~125% for 3/16inch tube. From the results Ag nanofluid can be a better candidate as a coolant than distilled water when using in mechanical and/or electronic systems.

본 연구에서는 두 가지 종류의 미세관(외경 1/8inch, 3/16inch)을 사용하여 증류수 및 0.1vol.%, 0.3vol.%의 농도를 가지는 은 나노유체의 층류 유동 조건인 Re수 500~2,500의 범위에서 압력강하 및 나노유체의 열전달 계수를 실험적으로 구하였다. 압력강하의 경우 나노유체의 압력강하는 증류수에 비해 최대 21% 증가하였다. 대류열전달계수의 경우 나노유체 0.1vol%의 경우 증류수에 비해 1/8inch관에서는 약 3~42%, 3/16inch관에서는 약 3~69%의 향상이 있었다. 또한, 0.3vol%의 경우 1/8inch관에서는 약 35~65%, 3/16inch관에서는 약 62~125%의 향상이 있는 것을 알 수 있었다. 이상의 결과에서 은나노유체를 기계 및 전자 시스템의 냉각제로 사용할 경우 증류수에 비해 매우 우수한 냉각성능을 보일 것으로 판단된다.

Keywords

References

  1. Anoop, K. B., Patel, H. E., Sundararajan, T., and Das, S. K., "Numerical study of convective laminar heat transfer in nanofluids", Int. Heat Tran. Con., NAN-11, 2006.
  2. Hwang, K. S., Lee, J. H., and Jang, S. P., "Convective heat transfer and flow character- istics of Al2O3 Nanoparticles Suspended in water under the laminar flow regime", KSME, pp. 2319-2324, 2006.
  3. Lee, J. H., and Jang, S. P., "Fluid flow characteristics of Al2O3 Nanoparticles suspended in water", KSME, Vol. 30, No. 6, pp. 546-552, 2006.
  4. Maxwell, J. C., "A Treatise on Electricityand Magnetism", vol 1 (Oxford: Clarendom), 1873.
  5. Lee, K. I. et al., "Heat and Mass Transfer characteristic in nanofluids", Proceedings of the SAREK '06 Winter Annual Conference, pp. 525-532, 2006.
  6. Jang, S. P. and Choi, S. U. S., "Role of Brownian motion in the enhanced thermal conductivity of nanofluids", Appl. Phys. Lett., Vol. 84, pp. 4316-4318, 2004. https://doi.org/10.1063/1.1756684
  7. Davalos-Orozco, L. A. and Del Castillo, L. F., "Hydrodynamic behavior of suspensions of polar particles: in Encyclopedia of surface and colloid science", Marcel Dekker, New York, pp. 2375-2396, 2002.
  8. Smith, J. M. and Van Ness, H. C., "Introduction to chemical engineering thermodynamics", McGraw Hill, New York, 1987.
  9. Jang, S. P. and Choi, S. U. S., "Free convection in rectangular cavity with nanofluids", IMECE2004-61054 Anheim, USA, 2004.
  10. Yunus Cengel., "Introduction to Thermodynamics & Heat Transfer", Mc Graw Hill, 1996.