在相對運動組件之接觸面，潤滑油已被廣泛使用來延長組件之壽命。雖然如此，潤滑油常受到工作溫度、機械應力、剪力而降解並產生氧化及基礎油分解產物，導致組件損壞而使機器故障，大大增加維修成本。因此，潤滑油之檢測是預防失效之最低成本方法。本研究為能兼併有效且即時的檢測潤滑油性能，研發一創新之潤滑油品質量測系統，可將潤滑油於靜態與動態之環境下，進行測試。當在靜態之荷重環境下，對潤滑油進行升溫加熱，觀測黏度指數與導電度之關聯。當潤滑油於稼動轉速(700–1300 rpm)與控制溫度(40–90°C)之動態操作下，可量測潤滑油之數據變異:極間之放電能量、傳遞扭力、熱傳導係數及潤滑油色彩值。當應用隨機化完全區集設計，可分析潤滑油於量測品質之變異。結果顯示，稼動轉速與控制溫度為影響傳遞扭力與熱傳導係數之顯著因子。說明量測系統之稼動轉速與控制溫度可作為量測及評估傳遞扭力與熱傳導係數之變異。此外，隨溫度提高，潤滑油逐漸由亮變黑及從黃變到深藍，控制溫度為影響潤滑油色彩L值(亮度)與B值(黃–藍)之顯著因子。因此，本系統藉由控制溫度對油膜顏色產生效應，作為量測與判斷潤滑油之變異。當以殘差分析計算隨機之殘差，可得量測指標之殘差分佈於線性擬合之精度(R2)，分別為傳遞之扭力為87%、熱傳導係數為78%、色彩L值為72%及色彩B值為96%，亦即潤滑油之品質變異可藉由本系統之量測指標作為評估。

Lubricating oil has been widely used on the contact surface of relative moving components to reduce energy consumption and extend the life of components. Nevertheless, lubricating performance is often subject to changes by working temperature, shear stress, aging, and pollutants. As a result, degradations of lubricating performance on the oxidation, nitrification, sulfation, and decomposition products, leading to mechanical damages and failures, which greatly increases cost of repairs and maintenance. Therefore, detection of the lubricating performance in the upfront is necessitated for energy savings and given manufacturing. In order to incorporate effective and in-time detection of lubricant performance, this study has developed an novel design of measurement device for lubricant performance that can test lubricants in static and dynamic environments. When measurements are carried out under a static load, the alternations of the lubricated performance are observed with the correlation between viscosity index and electrical conductivity. When measurements are under the dynamic conditions with parameters of the loaded rotational speed (700–1300 rpm) and the controlled temperature (40–90°C), the recorded discharge energy between the electrodes, the load-bearing torque, the thermal conductivity and the colour value of the oil film are analysed and discussed. Based on the randomized complete block design, the variations and errors on indicators are correlated with measuring condition. In ANOVA, the measurement results show that the loaded rotational speed and the controlled temperature are significant factors for measuring the load-bearing torque and thermal conductivity. Both can be used to observe the effect on the oil, which can be used to measure and evaluate the load-bearing torque and heat transfer. On the other hand, the colour index value decreases with the increase of temperature, prompting the oil film to gradually change from bright to black and from orange to dark blue. The controlled temperature is a significant factor affecting the lubricating oil colour L index (brightness) and B index (yellow-blue). Therefore, evaluations of colour value of L and B can be used to judge the aging of lubricant performance by controlling the temperature. When the random error of the measurement value is calculated by residual analysis, the error distribution in the linear fitting accuracy (R2) of the measurement index are obtained. The precision levels of the bearing torque, thermal conductivity, colour brightness (L) and colour B index value are 87%, 78%, 72% and 96%, respectively. The established measuring system are tested and reliable for the evaluations of the lubrication performance in multiple objectives.

[1] E. Daschner, D.M. Pirro, M. Webster, Lubrication Fundamentals, Third Edition, Revised and Expanded-CRC Press, 2016.
[2] A.A. Wessol, D.M. Pirro, Lubrication Fundamentals, Second Edition -CRC Press, 2001.
[3] T. Mang, S. Noll, T. Bartels, Lubricants, Fundamentals of Lubricants and Lubrication, Ullmann's Encyclopedia of Industrial Chemistry, 2011.
[4] J.M. Wakiru, L. Pintelon, P.N. Muchiri, P.K. Chemweno, A review on lubricant condition monitoring information analysis for maintenance decision support, Mechanical Systems and Signal Processing, 118 (2019) 108-132.
[5] P.D. Brito, Effect of Lubricant Degradation on the Tribological Performance, Universidad Nacional de Colombia, 2014.
[6] F.J. Owuna, Stability of vegetable based oils used in the formulation of ecofriendly lubricants – a review, Egyptian Journal of Petroleum, 29 (2020) 251-256.
[7] C.C. Fraenza, E. Förster, G. Guthausen, H. Nirschl, E. Anoardo, Use of 1H-NMR spectroscopy, diffusometry and relaxometry for the characterization of thermally-induced degradation of motor oils, Tribology International, 153 (2021) 106620.
[8] S. Zzeyani, M. Mikou, J. Naja, A. Elachhab, Spectroscopic analysis of synthetic lubricating oil, Tribology International, 114 (2017) 27-32.
[9] F.C.P. Ribeiro, A.S. Oliveira, A. Araújo, W. Marinho, M.P. Schneider, L. Pinto, A.A. Gomes, Detection oxidative degradation in lubricating oil under storage conditions using digital images and chemometrics, Microchemical Journal, 147 (2019) 622-627.
[10] J. Sentanuhady, W. Saputro, M.A. Muflikhun, Metals and chemical compounds contaminants in diesel engine lubricant with B20 and B100 biofuels for long term operation, Sustainable Energy Technologies and Assessments, 45 (2021) 101161.
[11] R.M. Mortier, S.T. Orszulik, Chemistry and technology of lubricants, Glasgow London : Blackie, Glasgow London, 1992.
[12] J.A. Heredia-Cancino, M. Ramezani, M.E. Álvarez-Ramos, Effect of degradation on tribological performance of engine lubricants at elevated temperatures, Tribology International, 124 (2018) 230-237.
[13] K. Motahari, M. Abdollahi Moghaddam, M. Moradian, Experimental investigation and development of new correlation for influences of temperature and concentration on dynamic viscosity of MWCNT-SiO 2 (20-80)/20W50 hybrid nano-lubricant, Chinese Journal of Chemical Engineering, 26 (2018) 152-158.
[14] M. Afrand, K. Nazari Najafabadi, M. Akbari, Effects of temperature and solid volume fraction on viscosity of SiO2-MWCNTs/SAE40 hybrid nanofluid as a coolant and lubricant in heat engines, Applied Thermal Engineering, 102 (2016) 45-54.
[15] S. Narayanasarma, B.T. Kuzhiveli, Evaluation of lubricant properties of polyolester oil blended with sesame oil-An experimental investigation, Journal of Cleaner Production, 281 (2021) 125347.
[16] M.E. Soltani, K. Shams, S. Akbarzadeh, A. Ruggiero, A Comparative Investigation on the Tribological Performance and Physicochemical Properties of Biolubricants of Various Sources, a Petroleum-Based Lubricant, and Blends of the Petroleum-Based Lubricant and Crambe Oil, Tribology Transactions, 63 (2020) 1121-1134.
[17] A.A. Bhosale, K. Joshi, T. Karadkar, K. Mangidkar, P. Mundhe, Analysis of Lubricating Oil Deterioration in Four-Wheeler, Applied Mechanics and Materials, 446-447 (2013) 558-561.
[18] Y. Peng, T. Wu, S. Wang, Z. Peng, Oxidation wear monitoring based on the color extraction of on-line wear debris, Wear, 332-333 (2015) 1151-1157.
[19] A.S. Behnam Rahimi, Alireza Nezamzade Ejhieh , Hamid Shakoori Langeroodi, Mas, Dr., Application Of Icp-Oes In The Comparative Analysis Of A Used And Fresh Gasoline Motor Oil, Global Journal of Science Frontier Research, 12 (2012).
[20] T.J. Harvey, R.J.K. Wood, G. Denuault, H.E.G. Powrie, Effect of oil quality on electrostatic charge generation and transport, Journal of Electrostatics, 55 (2002) 1-23.
[21] S.I. El-Sisi, G.S.A. Shawki, Measurement of Oil-Film Thickness Between Disks by Electrical Conductivity, Journal of Basic Engineering, 82 (1960) 12-16.
[22] R.M. Charin, G.M.T. Chaves, K. Kashefi, R.P. Alves, F.W. Tavares, M. Nele, Crude Oil Electrical Conductivity Measurements at High Temperatures: Introduction of Apparatus and Methodology, Energy & Fuels, 31 (2017) 3669-3674.
[23] M. Torbacke, A.K. Rudolphi, E. Kassfeldt, Lubricant Properties, Lubricants, 2014, pp. 19-44.
[24] P. Radhika, C.B. Sobhan, S. Chakravorti, Improved tribological behavior of lubricating oil dispersed with hybrid nanoparticles of functionalized carbon spheres and graphene nano platelets, Applied Surface Science, 540 (2021) 148402.
[25] Y. Du, T. Wu, J. Cheng, R. Gong, Lubricating oil deterioration on a four-ball test rig via on-line monitoring, 2015.
[26] H. Wu, L. Wang, G. Dong, S. Yang, J. Zhang, B. Zhou, Z. Tang, Lubrication effectiveness investigation on the friendly capped MoS2 nanoparticles, Lubrication Science, 29 (2017) 115-129.
[27] L.I. Farfan-Cabrera, E.A. Gallardo-Hernández, M. Gómez-Guarneros, J. Pérez-González, J.G. Godínez-Salcedo, Alteration of lubricity of Jatropha oil used as bio-lubricant for engines due to thermal ageing, Renewable Energy, 149 (2020) 1197-1204.
[28] H. Wu, L. Wang, B. Johnson, S. Yang, J. Zhang, G. Dong, Investigation on the lubrication advantages of MoS2 nanosheets compared with ZDDP using block-on-ring tests, Wear, 394-395 (2018) 40-49.
[29] H. Wu, S. Yin, Y. Du, L. Wang, H. Wang, An investigation on the lubrication effectiveness of MoS2 and BN layered materials as oil additives using block-on-ring tests, Tribology International, 151 (2020) 106516.
[30] P.L. Menezes, Kishore, S.V. Kailas, M.S. Bobji, Influence of tilt angle of plate on friction and transfer layer—A study of aluminium pin sliding against steel plate, Tribology International, 43 (2010) 897-905.
[31] R. Balakumar, G. Sriram, S. Arumugam, Effect of Lubricant contaminated with Waste Ayurvedic Oil Biodiesel on Tribological Behavior of Cylinder Liner-Piston Ring Tribo pair Material, Materials Today: Proceedings, 5 (2018) 13220-13226.
[32] A. Zanobini, B. Sereni, M. Catelani, L. Ciani, Repeatability and Reproducibility techniques for the analysis of measurement systems, Measurement, 86 (2016) 125-132.
[33] S. Arumugam, P. Chengareddy, G. Sriram, Synthesis, characterisation and tribological investigation of vegetable oil-based pentaerythryl ester as biodegradable compressor oil, Industrial Crops and Products, 123 (2018) 617-628.
[34] S.S. Sanukrishna, M. Shafi, M. Murukan, M. Jose Prakash, Effect of SiO2 nanoparticles on the heat transfer characteristics of refrigerant and tribological behaviour of lubricant, Powder Technology, 356 (2019) 39-49.
[35] W. Żurowski, J. Zepchło, D. Kanaška, M. Rucki, Concept and assessment of the novel design of tribological tester, Measurement, 170 (2021) 108724.
[36] D.C. Montgomery, Design and Analysis of Experiments, John Wiley & Sons, 2005.
[37] C. Chatfield, Statistics for Technology: A Course in Applied Statistics, Chapman and Hall/CRC, 1983.
[38] M. Kapsiz, M. Durat, F. Ficici, Friction and wear studies between cylinder liner and piston ring pair using Taguchi design method, Advances in Engineering Software, 42 (2011) 595-603.
[39] P. Thapliyal, G.D. Thakre, Correlation Study of Physicochemical, Rheological, and Tribological Parameters of Engine Oils, Advances in Tribology, 2017 (2017) 1-12.
[40] A. Suhanea, R.M. Sarviyab, A.R. Siddiquib, H.K. Khairac, Optimization of Wear Performance of Castor Oil based Lubricant using Taguchi Technique, Materials, 4 (2017) 2095-2104.
[41] S. Hisham, K. Kadirgama, D. Ramasamy, M.M. Noor, A.K. Amirruddin, G. Najafi, M.M. Rahman, Waste cooking oil blended with the engine oil for reduction of friction and wear on piston skirt, Fuel, 205 (2017) 247-261.
[42] B.E. Rapp, Continuity and Navier-Stokes Equations in Different Coordinate Systems, in: B.E. Rapp (Ed.) Microfluidics: Modelling, Mechanics and Mathematics, Elsevier, Oxford, 2017, pp. 303-308.
[43] O. Reynolds, "On the Theory of Lubrication and Its Application to Mr. Beauchamp Tower's Experiments, Including an Experimental Determination of the Viscosity of Olive Oil", Philosophical Transactions of the Royal Society of London, 177 157-234 (1886).
[44] F.W. Ocvirk, Short-bearing Aprroximation for Full Journal Bearings, 1952.
[45] A.A. Raimondi, J. Boyd, A Solution for the Finite Journal Bearing and its Application to Analysis and Design: I, A S L E Transactions, 1 (1958) 159-174.
[46] R.W.G. Hunt, M.R. Pointer, Measruing Colour, Fourth edition-John Wiley & Sons, 2011.