Effects of non-Newtonian micropolar fluids on the squeeze-film characteristics between a sphere and a plate surface

The aim of this paper is to presents a theoretical analysis on squeeze-film characteristics of a rough porous circular stepped plate in the vicinity of pressure-dependent viscosity and lubrication by micropolar fluids. A closed-form expression for non-dimensional pressure, load, and squeezing time is derived based on Eringen’s theory, Darcy’s equation, and Christensen’s stochastic approach. Results indicate that the effects of pressure-dependent viscosity, surface roughness, and micropolar fluids play an important role in increasing the load-carrying capacity and squeezing time, whereas the presence of porous media decreases the load-carrying capacity and squeezing time of the rough porous circular stepped plates.

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Non-Newtonian Micropolar Fluid Squeeze Film Between Conical Plates

Zeitschrift für Naturforschung A ◽

10.5560/zna.2012-0036 ◽

2012 ◽

Vol 67 (6-7) ◽

pp. 333-337 ◽

Cited By ~ 3

Author(s):

Jaw-Ren Lin ◽

Chia-Chuan Kuo ◽

Won-Hsion Liao ◽

Ching-Been Yang

Keyword(s):

Micropolar Fluid ◽

Reynolds Equation ◽

Fluid Model ◽

Load Capacity ◽

Numerical Results ◽

Squeeze Film ◽

Micropolar Fluids ◽

Newtonian Case ◽

Film Characteristics ◽

Film Lubrication

By applying the micropolar fluid model of Eringen (J. Math. Mech. 16, 1 (1966) and Int. J. Mech. Sci. 31, 605 (1993)), the squeeze film lubrication problems between conical plates are extended in the present paper. A non-Newtonian modified Reynolds equation is derived and applied to obtain the solution of squeeze film characteristics. Comparing with the traditional Newtonian case, the non-Newtonian effects of micropolar fluids are found to enhance the load capacity and lengthen the approaching time of conical plates. Some numerical results are also provided in tables for engineer applications

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Squeeze Film Theory for Micropolar Fluids

Journal of Lubrication Technology ◽

10.1115/1.3452749 ◽

1976 ◽

Vol 98 (1) ◽

pp. 139-144 ◽

Cited By ~ 27

Author(s):

J. Prakash ◽

P. Sinha

Keyword(s):

Thin Films ◽

Flow Behavior ◽

Film Theory ◽

Continuum Theory ◽

Squeeze Film ◽

Micropolar Fluids ◽

Fluid Theory ◽

Film Characteristics ◽

Analytical Expressions ◽

Circular Disks

Needs’ experimental results on thin films deviate considerably from those predicted by the classical theory when the film thickness is less than 0.00127 mm. In recent years there has been a tendency to attribute this deviation to the inadequacy of the classical continuum theory to describe the fluid flow behavior when confined to narrow passages. In this paper the micropolar fluid theory is applied to the squeeze films for circular disks to explain Needs’ findings. An excellent qualitative agreement is found to exist between the results based on this analysis and Needs’ results. Analytical expressions are obtained for various squeeze film characteristics and effect of microstructure elaborated through graphs.

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