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74 46 1 1395 ! 109 - 116 * : [email protected] $%&’ ()*+ $%*, -.(% */ 0/ 12’3 4 15’ Fe 3 O 4 6745 8* 1+’/’9%*/ : -; * !" #$ % & $ %*< ! %’ & $ #$ % 1*= >? ( %( )!$ %’ & $ #$ @ *+ ), -. &/0 *, 12 3! %3 Fe3O4 ) )45 *+ ), -. -6/0 "% 3 Fe3O4 -. " 7 -3 .% 9 2 5: ;0 "% /0 3 Nytro Libra % *< )0= ;> -. ? .% ( =% -. @ 3 $ *22A 0 ’3 1% *, 12 )0 BC$ *+ " =% .0 %3 -6/0 3! *0$ 3 *+ " =% -. D ) :E 9F& G@3 )45 *+ 90 G@3 ) *: = $ 9 >H ? .3 0E /0 F4, -. I - , 12 & %3 J .K LM 0 /!, 75. 3 3N , ( , O( 3 *+ ), -. &/0 *, 12 1 / 0 % 3 / 0 F 3 L 3 % 7 % 5 / 9 -6/0 )45 *+ ), -. 3 % 5 / 6 % 4 / 2 .% $3 -. 3 % , 12 & O[ / .% &K < \ F " - 22A # 1[% &K < GA3 -. )0 A%4 3 1+ :1 *+ -. &/0 *, 12 = . Experimental Analysis of Colloidal and Powder Nanoparticles Effects on Theconvective Heat Transfer in Transformer Oil J. Ghasemi Assistant Professor, University of Zanjan, Department of Mechanical Engineering S. Jafarmadar Professor,University of Urmia, Department of Mechanical Engineering M. Nazari M.Sc. Student, University of Urmia, Department of Mechanical Engineering Abstract Experimental study of convective heat transfer in nano-fluid, containing Fe 3 O 4 powder nano-particles without stabilizer and nano-fluid containing colloidal nanoparticles of Fe 3 O 4 , with stabilizer, is the main aim of this work. For this purpose, the Nytro Libra oil, as a conventional oil in power transformers has been considered as the base oil. Results show thatthe use of nanoparticles, improves the base fluid heat transfer characteristics. Alsobased on the experimental observations, the use of nanoparticles in the powder form, decreases and in the colloidal form increases the dielectric properties of transformer oil. Hence, the thermal behavior of the two types of nano-oils would be important. The results in present study showed that the convective heat transfer coefficient of nano- fluid, containing nano-particles in the powder form in a tube with constant heat flux, and volume concentration of 0.1% and 0.3%, is 7% and 9.5% mare than nano-oil containing colloidal particles and also 6.5% and 2.4% higher than the base oil, respectively. Finally, thermal behavior of different nano-oils samples are discussed, and other researcher’s arguments are also taken into consideration. Keywords: Transformer Oil, Powder Nanoparticles, Colloidal Nano fluid, Heat Transfer.

Transcript of Fe 3O $% &’ ()* + $ %*, - .( % ˙*/ 0 ˜ / 8*˙ 1 + ’/ ’ 9 %*/ · 2020. 12. 13. · For this...

Page 1: Fe 3O $% &’ ()* + $ %*, - .( % ˙*/ 0 ˜ / 8*˙ 1 + ’/ ’ 9 %*/ · 2020. 12. 13. · For this purpose, the Nytro Libra oil, as a conventional oil in power transformers has been

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Experimental Analysis of Colloidal and Powder Nanoparticles Effects on Theconvective

Heat Transfer in Transformer Oil

J. Ghasemi Assistant Professor, University of Zanjan, Department of Mechanical Engineering S. Jafarmadar Professor,University of Urmia, Department of Mechanical Engineering M. Nazari M.Sc. Student, University of Urmia, Department of Mechanical Engineering

Abstract

Experimental study of convective heat transfer in nano-fluid, containing Fe3O4powder nano-particles without stabilizer and nano-fluid containing colloidal nanoparticles of Fe3O4, with stabilizer, is the main aim of this work. For this purpose, the Nytro Libra oil, as a conventional oil in power transformers has been considered as the base oil. Results show thatthe use of nanoparticles, improves the base fluid heat transfer characteristics. Alsobased on the experimental observations, the use of nanoparticles in the powder form, decreases and in the colloidal form increases the dielectric properties of transformer oil. Hence, the thermal behavior of the two types of nano-oils would be important. The results in present study showed that the convective heat transfer coefficient of nano-fluid, containing nano-particles in the powder form in a tube with constant heat flux, and volume concentration of 0.1% and 0.3%, is 7% and 9.5% mare than nano-oil containing colloidal particles and also 6.5% and 2.4% higher than the base oil, respectively. Finally, thermal behavior of different nano-oils samples are discussed, and other researcher’s arguments are also taken into consideration. Keywords: Transformer Oil, Powder Nanoparticles, Colloidal Nano fluid, Heat Transfer.

Page 2: Fe 3O $% &’ ()* + $ %*, - .( % ˙*/ 0 ˜ / 8*˙ 1 + ’/ ’ 9 %*/ · 2020. 12. 13. · For this purpose, the Nytro Libra oil, as a conventional oil in power transformers has been

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nanofluids, International Journal of Heat and Fluid Flow", vol. 21, no. 1, pp. 58-64, 2000. [3] Saeedinia M., Akhavan-Behabadi M., Razi P., "Thermal and rheological characteristics of CuO–Base oil nanofluid flow inside a circular tube", International Communications in Heat and Mass Transfer, vol. 39, no. 1, pp. 152-159, 2012. [4] Beheshti A., Shanbedi M., Heris S. Z., "Heat transfer and rheological properties of transformer oil-oxidized MWCNT nanofluid, Journal of Thermal Analysis and Calorimetry", vol. 118, no. 3, pp. 1451-1460, 2014. [5] Rea U., McKrell T., Hu L.-w., Buongiorno J., "Laminar convective heat transfer and viscous pressure loss of alumina–water and zirconia–water nanofluids, International Journal of Heat and Mass Transfer", vol. 52, no. 7, pp. 2042-2048, 2009. [6] Segal V., et al., "AC (60 Hz) and impulse breakdown strength of a colloidal fluid based on transformer oil and magnetite nanoparticles", Electrical Insulation, 1998.Conference Record of the, IEEE International Symposium on, IEEE, 1998. [7] Du Y.-f., et al., "Effect of TiO 2 nanoparticles on the breakdown strength of transformer oil. Electrical Insulation (ISEI)", Conference Record of the IEEE International Symposium on, IEEE, 2010. [8] Lee J.-C., Kim W.-Y., "Experimental Study on the Dielectric Breakdown Voltage of the Insulating Oil Mixed with Magnetic Nanoparticles", Physics Procedia, vol. 32, pp. 327-334, 2012. [9] Sheet M. s. d., MSDS, EFH-1 FERROFLUID Ferro Tech Co., 2007. [10] Chakraborty, Experimental Characterizations of the Magnetic and Thermal Properties of Ferrofluid, Thesis, Jadavpur University, 2008. [11] Pak B. C., Cho Y. I., "Hydrodynamic and heat transfer study of dispersed fluids with submicron metallic oxide particles", Experimental Heat Transfer an International Journal, vol. 11, no. 2, pp. 151-170, 1998. [12] Xuan Y., Roetzel W., "Conceptions for heat transfer correlation of nanofluids", International Journal of Heat and Mass Transfer, vol. 43, no. 19, pp. 3701-3707, 2000. [13] Yu W., Choi S., "The role of interfacial layers in the enhanced thermal conductivity of nanofluids: a renovated Maxwell model", Journal of Nanoparticle Research, vol. 5, no. 1-2, pp. 167-171, 2003. [14] Shah R. K., London A. L., "Laminar flow forced convection in ducts: a source book for compact heat exchanger analytical data: Academic press", 1978. [15] Shah R. K., Bhatti M., "Laminar convective heat transfer in ducts", Handbook of Single-Phase Convective Heat Transfer, pp. 3.1-3.137, 1987. [16] Keblinski P., Phillpot S., Choi S., Eastman J., "Mechanisms of heat flow in suspensions of nano-sized particles (nanofluids)", International journal

of heat and mass transfer, vol. 45, no. 4, pp. 855-863, 2002. [17] Eastman J., Choi U., Li S., Soyez G., Thompson L., DiMelfi R., "Novel thermal properties of nanostructured materials", Journal of Metastable and Nanocrystalline Materials, vol. 2, pp. 629-634, 1999. [18] Beckwith T. G., Marangoni R. D., Lienhard J. H., Mechanical measurements: Pearson Prentice Hall, 2007.