Externally Pressurized Thrust Spherical Bearing Performance Under Variable Lubricant Viscosity (Un-recessed Clearance Type)
International Journal of Mechanical Engineering and Applications
Volume 8, Issue 2, April 2020, Pages: 45-64
Received: Mar. 19, 2020;
Accepted: Apr. 7, 2020;
Published: Apr. 28, 2020
Views 189 Downloads 99
Ahmad Waguih Yacout Elescandarany, Mechanical Department, Faculty of Engineering, Alexandria University, Alexandria, Egypt
In a previous study handling this subject, a series of six papers has been published covering the fitted type (equal radii of this sort of bearings) with its configurations in details. The present study handles the same subject investigating the clearance type of this sort of bearings starting with the un-recessed one. The clearance type of bearings, where the sphere radius is smaller than that of the seat, provides plenty of complications and great divergence in its behavior compared with the fitted one. The study investigates theoretically the bearing behavior under the lubricant viscosity variation in the presence of the centripetal inertia due to the shaft rotation and the surface roughness. Solutions have been derived for the un-recessed clearance type of bearings with hemispherical and partial hemispherical seats in addition to its two special cases using capillary tube and orifice restrictors. Unlike other studies, using the conventional integration (i.e., without using the Sommerfeld substitution), only one equation with one form for the pressure gradient is derived to cover the positive and negative eccentricity ratios. Expressions for the pressure distribution, temperature distribution in turn the temperature rise, load carrying capacity; volume flow rate, frictional torque, friction factor, power losses and stiffness factor are obtained. The study shows the combined effects of the viscosity variation, the centripetal inertia and the surface roughness on the bearing performance. The optimum design (with constant viscosity) based on the minimum power losses, minimum flow rate and the optimal restrictor dimensions, in a previous study is checked where it is found out that designing this type of bearings on such basis only is not sufficient in despite of the bearing consistency. A natural dynamic phenomenon ignored in the previous study is revealed and briefly touched.
Ahmad Waguih Yacout Elescandarany,
Externally Pressurized Thrust Spherical Bearing Performance Under Variable Lubricant Viscosity (Un-recessed Clearance Type), International Journal of Mechanical Engineering and Applications.
Vol. 8, No. 2,
2020, pp. 45-64.
Ahmad W. Yacout, Ashraf S. Ismaeel, Sadek Z. Kassab, 2007, "The combined effects of the centripetal inertia and the surface roughness on the hydrostatic thrust spherical bearing performance", Tribolgy International Journal, Vol. 40, No. 3, 522-532.
Ahmad W. Yacout Elescandarany” The Effect of the Fluid Film Variable Viscosity on the Hydrostatic Thrust Spherical Bearing Performance in the Presence of Centripetal Inertia and Surface Roughness (Part 1, un-recessed fitted bearing); International journal of Mechanical Engineering and Applications 2018, Vol. 6, No. 1, pp. 1-12.
Ahmad Waguih Yacout Elescandarany” The Effect of the Fluid Film Variable Viscosity on the Hydrostatic Thrust Spherical Bearing Performance in the Presence of Centripetal Inertia and Surface Roughness (Part 2, recessed fitted bearing). International journal of Mechanical Engineering and Applications 2018, Vol. 6, No. 3, pp. 73-90.
Ahmad W. Yacout, Ismail, A. S. and Kassab, S. Z.,” The Surface Roughness Effect on the Hydrostatic Thrust Spherical Bearings Performance (Part 2 un-recessed clearance type of bearings), 2006, “ASME International Mechanical Engineering Congress and Exposition, Paper No. IMECE 2006-13004.
Woonsil Lee, Chi Hyuk, An Sung Lee, "A High Bearing Temperature Troubleshooting of Centrifugal Heat-Pump Compressor", 45thTurbo-machinery & 32nd pump symposia, Huston, Texas, 12-15, 2016, George R. Brown Convention Center.
Yongping SUN, Minghui HAO, Baoyu SONG, "Bearing capacity and temperature rise characteristics analysis of herringbone groove hydrodynamic lubricating bearing", 2nd International Forum on Electrical Engineering and Automation (IFEEA 2015).
Srinivasan V. “Analysis of Static and Dynamic Load on the Hydrostatic Bearing with Variable Viscosity Affected by the Environmental Temperature”, Journal of Environmental Research and Development 2012, Vol. 7, No. 1A, 346-353.
Srinivasan V. “Analysis of Static and Dynamic Load on Hydrostatic Bearing with Variable Viscosity and Pressure”, Indian Journal of Science and Technology 2013, Vol. 6 (6s), 4777-4782.
Shigang Wang, Xianfeng Du, Mingzhu Li, Zhongliang Cao, Jianjia Wang, Analysis of temperature effect on the lubricating state of hydrostatic bearing, Journal of Theoretical and Applied Information Technology 2013, Vol. 48, No. 2, 817-821.
Xibing Li, Xun Wang, Ming Li, Yunshi Ma and Ying Huang, The Research Status and Progress of Heavy/Large Hydrostatic Thrust Bearing, Hidawi Publishing Corporation, Advances in Mechanical Engineering, volume 2014, Article ID: 982584. http://dx.doi.org/10.1155/2014/982584.
N. B. Naduvinamani and Archana K. Kadadi, 2013, “The effect of viscosity variation on the micro-polar fluid squeeze film lubrication of a short journal bearing”, Advances of Tribology Journal, Vol. 2013, Article ID 743987.
B. Bouchehit, B. Bou-Saïd and M Garcia, 2016, “Static and dynamic performances of refrigerant-lubricated foil bearings”, 7th international conference on advanced concepts in mechanical engineering.
Yuan Kang, Jian-Lin Lee, Hua-Chin Huang and Ching-Chu Huang,” Design for static stiffness of hydrostatic plain bearings: Constant compensations”, Journal of Industrial Lubrication and Tribology 2011, Vol. 63, No. 3, pp: 178-191.
G Jaya Chandra Reddy, C Eswara Reddy, K Rama Krishna Prasad,” Effect of viscosity variation on the squeeze film performance of a narrow hydrodynamic journal bearing operating with couple stress fluids”, Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 2008, Vol. 222, No. 2, pp: 141-150.
Jun Sun, Xinlong Zhu, Liang Zhang, Xianyi Wang, Chunmei Wang, Hu Wang and Xiaoyong Zhao,” Effect of surface roughness, viscosity-pressure relationship and elastic deformation on lubrication performance of misaligned journal bearings”, Journal of Industrial Lubrication and Tribology 2014 Vol. 66, · No. 3, pp: 337–345.
Chuan-Chieh, Sheng-Yen Hu, Chao-Ping Huang and Yuan Kang, “Influences of Lubricant Viscosity Ratio on Static Characteristics of Hydrostatic Thrust Bearing”, MATEC Web of Conferences 2017, 114, 01006.