Numerical analysis of journal bearings lubricated with micropolar fluids including thermal and cavitating effects

• Published in: Tribology international Vol. 39; no. 3; pp. 227 - 237
• Main Authors: Wang, Xiao-Li, Zhu, Ke-Qin
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2006; Elsevier
• Subjects: Applied sciences; Bearings, bushings, rolling bearings; Cavitation; Drives; Exact sciences and technology; Friction, wear, lubrication; Journal bearing; Machine components; Mechanical engineering. Machine design; Micropolar fluids; Thermal effects; Cavitation; Micropolar fluids; Thermal effects; Journal bearing; Non Newtonian fluid; Leak; Temperature effect; Modeling; Thermohydrodynamic lubrication; Micropolar fluid; Energy equation; Size effect; Friction coefficient; Thermal fluid; Coupling; Newtonian fluid; Reynolds equation; Tribology
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2005.01.028

A numerical study of the non-Newtonian behavior for a finite journal bearing lubricated with micropolar fluids is undertaken considering both thermal and cavitating effects. The modified Reynolds equation and energy equation are derived based on Eringen's micropolar fluid theory. The solution to the modified Reynolds equation is determined using the Elord's cavitation algorithm. The effects of the size of material characteristic length and the coupling number on the thermohydrodynamic performance of a journal bearing are investigated. It is shown, compared with Newtonian fluids, that micropolar fluids exhibit the increase in load capacity and temperature, but the decrease in coefficient of friction and side leakage flow. It is also indicated that, in the full film region, micropolar fluids increase the values of non-dimensional density, while in the cavitated region, both micropolar fluids and Newtonian fluids yield the same values of the fractional film content.