Estimation of random friction forces on the microbearing cooperating surfaces

• Autorzy: Wierzcholski Krzysztof , Miszczak Andrzej

Identyfikatory

DOI

10.2478/kones-2019-0046

• Języki publikacji: EN

Abstrakty

EN

Presented paper concerns a new mathematical form of stochastic theory of hydrodynamic friction forces occurring on the real cooperating surfaces in computer micro bearing fan and computer microbearing in hard disc driver HDD. This paper presents particularly a new-review of stochastic analytical considerations realized by the authors for friction forces estimation during hydrodynamic lubrication performed on the ground of the measurements of the gap height between two roughness surfaces. After numerous experimental measurements directly follows that the random unsymmetrical increments and decrements of the gap height of computer microbearings have important influence on the load carrying capacities and finally on the friction forces and wear of cooperating surfaces. The main topic demonstrates the influence of the variations of expectancy values and standard deviation of the computer microbearing gap height on the friction forces occurring in the HDD and microbearing fan. Moreover, it is observed the evident connection between the apparent dynamic viscosity and the features of the microbearing superficial surface. Hence after abovementioned remarks follows the corollary that the influence of the microbearing gap height stochastic variations connected with the surface roughness tend moreover indirect from the apparent viscosity into the friction forces variations. The synthetic, complex elaboration of obtained results indicates finally the influence of the random roughness in micro and nano level of microbearing surfaces on the friction forces distribution. A new results contained in this paper are obtained taking into account 3D variations of dynamic viscosity of the non-Newtonian lubricant, particularly variations crosswise the film thickness and influences of surface superficial layer features on the lubricant apparent viscosity.

Słowa kluczowe

EN

microbearings; computer fan; hard disc driver bearings; hydrodynamic lubrication; analytical stochastic principles; analytical solutions; apparent viscosity depended on the gap height variations

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2019
• Tom: Vol. 26, No. 2
• Strony: 167--174
• Opis fizyczny: Bibliogr. 18 poz., rys.

Twórcy

autor

Wierzcholski Krzysztof

• Technical University of Koszalin, Faculty of Technology and Education Śniadeckich Street 2, 75-453 Koszalin, Poland tel.: [phone], fax: [phone]

autor

Miszczak Andrzej

• Gdynia Maritime University, Faculty of Marine Engineering Morska Street 81-87, 81-225 Gdynia, Poland tel.: [phone], fax: [phone]

Bibliografia

• [1] Asada, T., Saito, H., Asaida, Y., Itoh, K., Design of hydrodynamic bearings for high-speed HDD, Microsystem Technologies, Vol. 8, Iss. 2-3, pp. 220-226, 2002.
• [2] Asada, T. et al, Hydrodynamic bearings and applied technologies, Matsushita Tech., Vol. 46 (1), pp. 54-76, 2000.
• [3] Bhushan, B., Handbook of Micro/Nano Tribology, second ed. CRC Press, Boca Raton, London, New York, Washington D.C. 1999.
• [4] Bhushan, B., Nanotribology and nano-mechanics of MEMS/NEMS and BioMEMS/BioNEMS materials and devices, Microelectronic Engineering, Vol. 84, pp. 387-412, 2007.
• [5] Bhushan, B., Principles and applications of tribology, John Wiley and Sons, New York 1999.
• [6] Cwanek, J., The usability of the surface geometry parameters for the evaluation of the artificial hip joint wear, Rzeszów University Press, Rzeszów 2009.
• [7] Fisz, M., Probability Theory and Mathematical Statistics, J. Wiley & Sons, Inc., N.Y. 1963.
• [8] Jang, G. H., Lee, S. H., Kim, H. W., Kim, C. S., Dynamic analysis of a HDD spindle system with FDBs due to the bearing width and asymmetric grooves of journal bearing, Microsystem Technologies, Vol. 11, pp. 499-505, 2005.
• [9] Jang, G. H., Park, S. J., Kim, C. S., Han, J. H., Investigation of the electromechanical variables of the spindle motor and the actuator of HDD due to positioning and the free fall, Microsystem Technologies, Vol. 13, pp. 797-809, 2007.
• [10] Lee, J., Jang, G., Ha, H., Robust optimal design of the FDBs in a HDD to reduce NRRO and RRO, Microsystem Technologies, Vol. 18 (9-10), pp. 1335-1342, 2012.
• [11] Oczoś, K., Lubimov, V., Geometrical structure of surface (in Polish), Rzeszów University Publishing House, 2003.
• [12] Sharma, S., Hargreaves, D., Scott, W., Journal bearing performance and metrology issues, Journal of Achievements in Materials and Manufacturing Engineering, Vol. 32 (1), pp. 98-103, 2009.
• [13] Wierzcholski, K., Miszczak, A., Khudoley, A., The intelligent operation of nano grooved microbearing surfaces in computer HDD, Tribologia, No. 1 (241), pp. 157-166, 2012.
• [14] Wierzcholski, K., Miszczak, A., Electro-Magneto-Hydrodynamic Lubrication, Open Physics, Vol. 16 (1), pp. 285-291, 2018.
• [15] Wierzcholski, K., Miszczak, A., Khudoley, A., Measurement of non used microbearing occurring in computer HDD Seagate Barakuda, Journal of KONES Powertrain and Transport, Vol. 18, No. 2, pp. 477-482, 2011.
• [16] Wierzcholski, K., Miszczak, A., Khudoley, A., Measurement of non used microbearing grooved surfaces for computer ventilator Xilence Case Fan, Journal of KONES Powertrain and Transport, Vol. 18, No. 2, pp. 471-476, 2011.
• [17] Wierzcholski, K., Logical network design of microbearing systems. Journal of KONES Powertrain and Transport, Vol. 18, No. 2, pp. 455-462, 2011.
• [18] Yuan, C. Q., Peng, Z., Yan, X. P., Zhou, X. C., Surface roughness evaluation in sliding wear process, Wear, Vol. 265, pp. 341-348, 2008.

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).