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Analysis of the load carrying capacities and the friction force in the gap of the slide journal bearing lubricated with a non-Newtonian oil described by a power-law model

Miszczak A.

Journal of KONES

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2016

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Vol. 23, No. 3

327--335

EN

In this paper, the author presents the results of numerical calculations of load carrying capacities and friction forces in the gap of the slide journal bearing lubricated with an oil on the non-Newtonian's properties. In the studies, the power-law model has been assumed to describe the relationship between the stress tensors and shear rate tensors. The analytical and numerical calculations have been performed for the plain bearing, non-porous with a full wrap angle. It has been assumed isothermal, laminar and steady flow of lubricant in the gap of a slide bearing. Numerical calculations have been performed for the Gumbel’s boundary conditions and dimensionless lengths of the bearings like L=b/R =2;1.5;1; ½ and ¼. The flow-rate index and coefficient of consistency have been adopted based on the results of experimental studies of changes of dynamic viscosity in terms of a shear rate. It has been assumed that the apparent viscosity depends only on the shear rate. Dynamic viscosity of the engine oil, used in a gasoline engine with a capacity of 1800 cm3, has been tested on the Haake Mars III rheometer. The analytical solutions presented in the paper were based on more general derivations carried out by Professor K. Wierzcholski in his article: ‘Non-linear hydrodynamic lubrication in conjugated fields’ (publication in printing). In this paper, the key quantities such as components of vector of the velocity, hydrodynamic pressure and temperature were presented in the form of convergent power series. The values of load carrying capacities and friction forces were determined and compared for the event where the oil has properties of Newtonian and non-Newtonian. Calculations have been made for the dimensionless quantities.

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Effects of a Rayleigh step aspect ratio on the thermohydrodynamic behavior of power law lubricant flows

Jeddi L., Bonneau D., El Khlifi M.

International Journal of Applied Mechanics and Engineering

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2005

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Vol. 10, no spec

233-238

EN

The thermohydrodynamic behavior of the lubricant flow in a Rayleigh step is described by a mathematical model that uses the bidimensional Navier-Stokes and energy equations written in terms of the primary variables u, v, p and T. The non-Newtonian behavior of the lubricant is described by a power law model. The lubricant is assumed to be incompressible and the process is steady-state and laminar. The equations are solved simultaneously using the incremental load method associated with the Newton-Raphson method and the finite element formulation. The effects of a Rayleigh step aspect ratio on the velocities, pressure and temperature patterns for different power law index are investigated.

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Natural convection of power-law fluid

Uściłowska A., Stręk T.

Vibrations in Physical Systems

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2004

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Vol. 21

399--402