本研究針對四行程機車，添加兩種不同性質之奈米材料(二氧化矽與多壁奈米碳管)於原廠機油中，研究機車在運行時的燃料消耗率(km/L)、溫度特性變化及廢氣污染排放做為實驗成果的效益評估。本研究總共試驗了2.1、2.15、2.2、2.6、2.65與2.7 wt.%的複合奈米機油，最後選定綜效表現較佳的2.65 wt.%複合奈米機油。在磨潤實驗與熱傳導實驗中，複合奈米機油相較於原廠機油，平均降低37.75 %的磨耗量與提升12.3 %的熱傳導係數。在實車實驗中，經市區及定速的行車型態測試下，平均燃油消耗量(km/L)提升了7.5 %。在油門開度50 %的測試下，平路與爬坡(4度坡)車速增加了9.52及8.74 %。在行車測試的溫度量測中，缸壁與機油溫度分別降低6.3 %、6.9 %，排氣溫度上升26.6 %。在廢氣排放量測中，HC與CO總量減少了22.51 %、26.12 %，CO2排放提升了3.89 %，PM值排放在粒徑2 μm以下總量增加了47.34 %。實驗證實複合奈米機油可以提供引擎較佳潤滑與散熱之效果，並從排氣溫度、CO2與PM值的提升可以證實引擎燃燒變得更完全，並降低HC與CO之排放。

In this study, two different types of nanoparticles (SiO2 and MWCNT) were added to the base engine oil (20W40), which using on four-stroke motorcycle. A total of 2.1, 2.15, 2.2, 2.6, 2.65 and 2.7 wt.% of hybrid nano lubricant were tested in this study. Finally, 2.65 wt.% with better comprehensive effect was selected. In the tribology experimental and the thermal conductivity experiment has an average reduction of 37.75 % and 12.3% compared with the base oil. In the vehicle experiment, the average fuel consumption (km/L) increased by 7.5%, and the speed of the flat road and the climbing (four-degree slope) increased by 9.52 and 8.74%. The temperature characteristics during the driving test, the cylinder wall and the oil temperature was reduced by 6.3% and 6.9%, the exhaust temperature was increased by 26.6%. In the exhaust emissions, the total amount of HC and CO decreased by 22.51% and 26.12%, the CO2 emission increased by 3.89%, and the PM value increased by 47.34% under the particle size of 2 μm. Experiments have confirmed that the hybrid nano lubricant can provide better lubrication to make the engine burn more completely and better heat dissipation.

[1] 台灣交通工具統計查詢網，中華民國交通部，2016年。
[2] 綠色車輛指南網，中華民國行政院環保署，2016年。
[3] 空氣汙染物排放查詢系統，中華民國行政院環保署，2016年。
[4] M. K. A. Ali, H. Xianjun, R. F. Turkson and M. Ezzat, ”An analytical study of tribological parameters between piston ring and cylinder liner in internal combustion engines”,Proc. Inst. Mech. Eng. K: J. Multibody Dyn. 2015.
[5] P. J. Blau, “A Review of Sub-scale Test Methods to Evaluate the Friction and Wear of Ring and Liner Materials for Spark- and Compression-ignition Engines”, Oak Ridge National Laboratory Tech. Report, vol. 184, pp. 12-19, 2001.
[6] X. Ge, Y. Xia and Z. Cao, “Tribological properties and insulation effect of nanometer TiO2 and nanometer SiO2 as additives in grease” , Tribology International, vol. 92, pp. 454-461, 2015.
[7] T. Luo, X. Wein, X. Huang, L. Huang and F. Yang, “Tribological properties of Al2O3 nanoparticles as lubricating oil additives”, Ceramics International, vol. 40,pp. 7143-7149, 2014.
[8] Y. Wu, W. Tsui and T. Liu, “Experimental analysis of tribological properties of lubricating oils with nanoparticle additives”, Wear, vol. 262, iss. 7-8, pp. 819-825, 2007.
[9] D. Gong, C. A. Grimes, O. K. Varghese, W. C. Hu, R. S. Singh, Z. Chen and E. C. Dickey, “Titanium oxide nanotube arrays prepared by anodic oxidation”, J. Mater. Res., vol. 16, iss. 12, pp. 3331-3334, 2001.
[10] M. Laad and V. K. S. Jatti, ”Titanium oxide nanoparticles as additives in engine Oil”, Journal of King Saud University-Engineering Sciences, vol. 30, iss. 2, pp. 116-122 2018.
[11] H. J. Song, Z. Z. Zhang and X. H. Men, “The tribological behaviors of the polyurethane coating filled with nano-SiO2 under different lubrication conditions”, Composites Part A: Applied Science and Manufacturing, vol. 39, iss. 2, pp. 188-194, 2008.
[12] M. K. A. Ali and H. Xianjun, “Improving the tribological behaviour of internal combustion engines via the addition of nanoparticles to engine oils”, Nanotechnol. Rev, pp. 347-358, 2015.
[13] G. Narendara, K. S. Gupta, A. Krishnaiaha and M. G. V. Satyanarayanac “Experimental investigation on the preparation and applications of Nano fluids”, Materials Today: Proceedings, vol. 4, iss. 2, pp. 3926-3931, 2017.
[14] S. Shahnazar, S. Bagheri, S. B. A. Hamid, “Enhancing lubricant properties
by nanoparticle”, International journal of hydrogen energy, vol. 41, pp. 3153-3170, 2016.
[15] D. Kumar and A. V. Arasu ,“A comprehensive review of preparation, characterization, properties and stability of hybrid nanofluids”, Renewable and Sustainable Energy Reviews, vol. 81, pp. 1669-1689, 2017.
[16] S. Shahnazar, S. Bagheri and S. B. A. Hamid, “Enhancing lubricant properties by nanoparticle additives”, International Journal of Hydrogen Energy, vol. 41, iss. 4, pp. 3153-3170, 2016.
[17] E. Dardan, M. Afrand and A. M. Isfahani, “Effect of suspending hybrid nano-additives on rheological behavior of engine oil and pumping power”, Appl. Therm. Eng.,vol. 109 , pp. 524-534, 2016.
[18] I. M. Hutchings, “Leonardo da Vinci׳s studies of friction”, Wear, vol. 360-361, pp. 51-66, 2016.
[19] A. Cameron, “Osborne Reynolds”, Tribology Series, vol 11, pp. 3-13, 1987.
[20] D. Tabor, “History of tribology: D. Dowson”, Tribology International, vol. 12, iss 3, pp 146, 1979.
[21] M. Hirano, “Atomistics of friction”, Surface Science Reports, vol. 60, iss. 8, pp. 159-201, 2006.
[22] A. Z. Szeri, “Tribology” , Encyclopedia of Physical Science and Technology (Third Edition), pp. 127-152, 2003.
[23] S. U. S. Choi, “Thermal Conductivity of Fluids With Nanoparticles”, Proc. ASME Int. Mech. Eng. Congr. Expo, vol. 66, pp. 99-105, 1995.
[24] M. H. Esfe, A. Karimipour, W.M. Yan, M. Akbari, M.R. Safaei and M. Dahari,“Experimental study on thermal conductivity of ethylene glycol based nanofluids containing Al2O3 nanoparticles”,Int. J. Heat Mass Transf, vol. 88, pp. 728-734, 2015.
[25] M. H. Esfe, S. Saedodin, M. Akbari, A. Karimipour, M. Afrand, S. Wongwises, M. R. Safaei and M. Dahari,“Experimental investigation and development of new correlations for thermal conductivity of CuO/EG–water nanofluid”, Int. Commun. Heat Mass Transfer, vol. 65, pp. 47-51, 2015.
[26] M. Soltanimehr and M. Afrand,“Thermal conductivity enhancement of COOH-functionalized MWCNTs/ethylene glycol–water nanofluid for application in heating and cooling systems”, Appl. Therm Eng, vol. 105, pp.716-723, 2016.
[27] R. Saidur and K. Y. Leong, ”A review on applications and challenges of nanofluids”,Renew. Sust. Energ. Rev, vol. 15, pp. 1646-1668, 2011.
[28] R. S. Vajjha and D. K. Das, ”A review and analysis on influence of temperature and concentration of nanofluids on thermophysical properties, heat transfer and pumping power”, Int. J. Heat Mass Transf.,vol. 55, pp. 4063-4078, 2012.
[29] P. Keblinski, S. Phillpot, S. Choi and J. Eastman, “Mechanisms of heat flow in suspensions of nano-sized particles (nanofluids)”, Int. J. Heat Mass Transf.,vol. 45, pp. 855-863, 2002.
[30] P Keblinski, S. R. Phillpot, S. U. S. Choi and J. A. Eastman, “Mechanisms of heat flow in suspensions of nano-sized particles (nanofluids)”, International Journal of Heat and Mass Transfer, vol. 45, pp. 855-863, 2002.
[31] M. H. Ahmadi, A. Mirlohi, M. A. Nazari and R. Ghasempour, “A review of thermal conductivity of various nanofluids”, Journal of Molecular Liquids, vol. 265, pp. 181-188, 2018.
[32] 楊謦豪，“奈米流體中粒子聚結及其對熱傳導係數的影響”，碩士論文，國立臺灣大學，2016年。
[33] A. Einstein, “A new determination of molecular dimensions”, Ann Phys, 4, pp. 37-62, 1906.
[34] H.C. Brinkman, “The viscosity of concentrated suspensions and solutions”, J Chem Phys, 20, pp. 571-581, 1952.
[35] G. Batchelor, “The effect of Brownian motion on the bulk stress in the suspension of sphrerical particles”, J Fluid Mech,vol. 83 , pp. 97-117, 1977.
[36] I. M. Krieger and T. Dougherty, “A mechanism for non-newtonian flow in suspensions of rigid spheres”, Trans Soc Rheol, vol. 3, pp. 137-152, 1959.
[37] S. H. Maron, P. E. Pierce, “Application of Ree-Eyring generalized flow theory to suspensions of spherical particles”, J Colloid Sci, 11 , pp. 80-95, 1956.
[38] J. C. Maxwell, “A Treatise on Electricity and Magnetism”, second ed (Oxford University Press), pp.435-441, 1904.
[39] R. L. Hamilton and O. Crosser, “Thermal conductivity of heterogeneous two component systems”, I&EC Fundamentals, vol. 3, pp. 187-191, 1962.
[40] J. A. Eastman, S. U. S. Choi, S. Li, W. Yu and L.J.Thompson, “Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles” , Applied Physics Letters, vol. 6, pp. 718-720, 2001.
[41] W. Yu and S. U. S. Choi, “The role of interfacial layer in the enhance thermal conductivity of nanofluid: a renovated Maxwell model”, Journal of Nanoparticle Research, vol. 5 , pp.167-171, 2003.
[42] T. Luo, X. Wein, X. Huang, L. Huang and F. Yang, “Tribological properties of Al2O3 nanoparticles as lubricating oil additives”, Ceramics International, vol. 40, pp. 7143-7149, 2014.
[43] A. K. Sharma, A. K. Tiwari and A. R. Dixita, “Characterization of TiO2, Al2O3 and SiO2 Nanoparticle based Cutting Fluids”, materialstoday:Proceedings, vol. 3, pp. 1890-1898, 2016.
[44] Y. Zhao, X. Qi, Y. Dong, J. Ma, Q. Zhang, L. Song, Y. Yang and Q. Yang, “Mechanical, thermal and tribological properties of polyimide/nano-SiO2 composites synthesized using an in-situ polymerization”, Tribology International, vol. 103, pp. 599-608, 2016
[45] H. Xie, B. Jiang, J. He, X. Xia and F. Pan, “Lubrication performance of MoS2 and SiO2 nanoparticles as lubricant additives in magnesium alloy-steel contacts”, Tribology International, vol. 93, pp. 63-70, 2016.
[46] A. K. Sharma, A. K. Tiwari, A. R. Dixit and R. K. Singh, “Investigation into Performance of SiO2 Nanoparticle Based Cutting Fluid in Machining Process”, materialstoday:PROCEEDINGS, vol. 4, pp. 133-141, 2017.
[47] 羅士庭，“添加奈米二氧化矽於四行程機車機油中綜合性能與廢氣排放影響之研究”，碩士論文，國立臺灣師範大學，2018年。
[48] Z. Zhang and F. E. Lockwood, “Preparation of stable nanotubes dispersions in liquids”, US Patent, US6783746B1, 2004.
[49] S. Iijima, “Helical microtubules of graphitic carbon”, Nature, vol. 354 , pp. 56-58, 1991.
[50] Y. Ding, H. Alias, D. Wen and R. A.Williams, “Heat transfer of aqueous suspensions of carbon nanotubes (CNT nanofluids)”, International Journal of Heat and Mass Transfer, vol. 49, iss. 1-2, pp. 240-250, 2006.
[51] P. Garg, J. L. Alvarado, C. Marsh, T. A. Carlson, D. A. Kessler and K. Annamalai, “An experimental study on the effect of ultrasonication on viscosity and heat transfer performance of multi-wall carbon nanotube-based aqueous nanofluids”, International Journal of Heat and Mass Transfer, vol. 52, iss. 21-22, pp. 5090-5101, 2009.
[52] S. U. Ilyas, R. Pendyala and M. Narahari, “Stability and thermal analysis of MWCNT-thermal oil-based nanofluids”, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol. 527, pp. 11-22, 2017.
[53] S. U. S. Choi, Z. G. Zhang, W. Yu , F. E. Lockwood, E. A. Grulke, “Anomalous thermal conductivity enhancement in nanotube suspensions”, Appl. Phys. Lett. vol. 79, pp. 2252, 2001.
[54] E. Ettefaghi, H. Ahmadi, A. Rashidi, A. Nouralishahi and S. S. Mohtasebi, “Preparation and thermal properties of oil-based nanofluid from multi-walled carbon nanotubes and engine oil as nano-lubricant”, Int. Commun. Heat Mass Transf, vol. 46, pp. 142-147, 2013.
[55] A. Alasli, T. Evgin and A. Turgut, “Re-dispersion ability of multi wall carbon nanotubes within low viscous mineral oil”, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol. 538, pp. 219-228, 2018.
[56] M. H. Hamzah, N. A. C. Sidik, T. L. K. R. Mamat and G. Najafi, “Factors affecting the performance of hybrid nanofluids: A comprehensive review”, International Journal of Heat and Mass Transfer, vol. 115, pp. 630-646, 2017.
[57] N. A. C. Sidik, M. M. Jamil, W. M. A. A. Japar and I. M. Adamu, “A review on preparation methods, stability and applications of hybrid nanofluids”, Renewable and Sustainable Energy Reviews, vol. 80, pp. 1112-1122, 2017.
[58] M. H. Hamzah, N. A. C Sidik, T. L. K. R. Mamat and G.Najafi, “Factors affecting the performance of hybrid nanofluids: A comprehensive review”, International Journal of Heat and Mass Transfer, vol. 115, pp. 630-646, 2017.
[59] D. Jiao, S. Zheng,Y. Wang, R. Guana and B. Cao, “The tribology properties of alumina/silica composite nanoparticles as lubricant additives”, Applied Surface Science, vol. 257, pp. 5720-5725, 2011.
[60] M. K. A. Ali, H. Xianjun, L. Mai, C. Bicheng, R. F. Turksona and C. Qingping, “Reducing frictional power losses and improving the scuffing resistance in automotive engines using hybrid nanomaterials as nano-lubricant additives”, Wear, vol. 364–365, pp. 270-281, 2016.
[61] K. Motahari, M. A. Moghaddama and M. Moradianl, “Experimental investigation and development of new correlation for influences of temperature and concentration on dynamic viscosity of MWCNT-SiO2 (20-80)/20W50 hybrid nano-lubricant”, Chinese Journal of Chemical Engineering, vol. 24, 2017.
[62] 許良明、黃旺根，汽車學I (汽油引擎篇)，台科大圖書，2008年。
[63] 機器腳踏車燃料消耗量試驗方法，行政院環保署，2009年。
[64] ASTM G99-95a, Standard test method for wear testing with a pin-on-disk apparatus, 2000.
[65] H. Riazi, T. Murphy, G. B. Webber, R. Atkin, S. S. M. Tehrani and R. A. Taylor,” Specific heat control of nanofluids: A critical review”, Int. J. of Therm Sci, vol. 107, pp. 25-38, 2016.