Author:
Abbaspur Ali,Norouzi Mahmood,Akbarzadeh Pooria,Vaziri Seyyed Amirreza,Sharghi Melika Mokhtari,Kim Kyung Chun,Kim Mirae
Abstract
AbstractThis paper presents a novel analytical solution for journal-bearing viscoelastic lubrication using the perturbation method. The nonlinear Giesekus model was used for the constitutive equations to study the effects of fluid elasticity, shear-thinning viscometric functions, and strain-hardening elongational viscosity of viscoelastic lubrication. The investigation focuses on the impact of characteristic parameters such as mobility factor, eccentricity ratio, and Weissenberg number on the fluid film pressure distribution, load capacity, and shear stress. Although distinguishing between the normal stress differences and extensional viscosity in mixed viscoelastic flows is complicated, we investigated the role and contribution of these two factors. By increasing the elasticity of the fluid, the portion of both mentioned parameters increases consequently. Furthermore, analyses and comparisons show the contributions of the first normal stress and elongational viscosity to the load capacity of the bearing through the stress ratio and flow type parameter for the first time. The research findings indicate that fluid elasticity enhances the load capacity of the bearing compared to a Newtonian lubricant with the same effective viscosity. Moreover, the bearing load capacity is divided into two regions. In the linear region, the mobility factor and Weissenberg numbers have minimal effects leading to a linear increase in the load distribution, and in the exponential region, the load capacity changes are considerable. This research provides valuable insights into the behavior of viscoelastic lubrication in journal-bearing systems.
Funder
National Research Foundation of Korea
Publisher
Springer Science and Business Media LLC
Reference71 articles.
1. Tower, B. First report on friction experiments. Proceed. Institut. Mech. Eng. 34, 632–659 (1883).
2. Tower, B. Second report on friction experiments. Proc. Inst. Mech. Engrs. 36, 38–70 (1985).
3. Tower, B. Third report on friction experiments 173–205 (Proc. Inst. Mech. Engrs, 1888).
4. Reynolds, O. IV. 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 Trans. R. Soc. London 177, 157–234 (1886).
5. Philipzik, W. Zur hydrodynamischen Theorie der Schmiermittelreibung. ZAMM-J. Appl. Math. Mech. /Zeitschrift für Angewandte Mathematik und Mechanik 36, 51–60 (1956).