The problem of unsteady oscillatory flow and heat transfer in a horizontal composite porous medium is performed. The flow is modeled usi ng the Darcy-Brinkman equation. The viscous and Darcian dissipation terms are also included in the energy equation. The partial differential equations governing th e flow and heat transfer are solved analytically using two-term harmonic and non-harmonic functions in both regions of the channel. Effect of the physical parameters such as the porous medium parameter, ratio of viscosity, oscillation amplitude, conductivity r atio, Prandtl number and the Eckert number on the velocity and/or temperature fields are shown gr aphically. It is observed that both the velocity and temperature fields in the channel d ecrease as either of the porous medium parameter or the viscosity ratio increases while they increase with increases in the oscillation amplitude. Also, increasing the thermal co nductivity ratio is found to suppress the temperature in both regions of the channel. The effects of the Prandtl and Eckert numbers are found to decrease the thermal state in the channel as well.

https://www.journals.vu.lt/nonlinear-analysis/article/download/14503/13434

Unsteady Oscillatory Flow and Heat Transfer in a Horizontal Composite Porous Medium Channel

Hydrodynamic lubrication of porous journal bearings using a modified Brinkman-extended Darcy model

In this report, we discuss the unique features which are introduced into the theory of hydrodynamic lubrication of bearings when the bearings are permeable and tolerate a flow of oil. The subject of the analysis is not entirely new, and a few aspects of the problem have been treated by several authors [1, 2, 4, 5, 9].

Lubrication of a Porous Bearing—Reynolds’ Solution

Numerical study of the thermo-hydrodynamic lubrication phenomena in porous journal bearings

Theoretical study of porous slider bearing with couple stress fluid as lubricant is made and the lubrication qualities of couple stress fluid are examined. The lower surface is covered by a thin porous material and the upper one, having arbitrary shape, moves in its own plane with constant velocity. Analytical expressions for load capacity, frictional force and the centre of pressure are derived. It yields increase in, load capacity and ensures the decrease in coefficient of friction. The problem is also discussed in the context of various geometries viz, (1) Rayleigh step bearings and (2) inclined slider bearings. Bounds on flow rate, frictional coefficient, centre of pressure and time-height relation are obtained and compared with classical case, Gross [1]. Suitable design parameters are predicted for the efficient lubrication of slider bearings.

Porous slider bearing with couple stress fluid

The theory of the operation of porous metal bearings as given in the 1957 Conference on Lubrication and Wear has now been extended. The analysis of a 360° porous bearing leads to a critical value o...

A. Cameron

Papers

Critical Conditions for Hydrodynamic Lubrication of Porous Metal Bearings