The Magnetohydrodynamic Journal Bearing

1963 ◽  
Vol 85 (3) ◽  
pp. 424-427 ◽  
Author(s):  
Dennis C. Kuzma

An analysis of an infinite journal bearing is presented for the case of an electrically conducting fluid in the presence of a magnetic field. The magnetohydrodynamic form of Reynolds’ bearing equation is derived and solved for the pressure distribution. The load carrying capacity is determined from the pressure distribution. Numerical data are presented for nonconducting bearing surfaces. These data are compared with the data from the ordinary journal bearing. It is shown that the load carrying capacity is increased by the application of a magnetic field.

1964 ◽  
Vol 86 (3) ◽  
pp. 445-448 ◽  
Author(s):  
D. C. Kuzma

An analysis of a finite journal bearing is presented for the case of an electrically conducting fluid in the presence of a radial magnetic field. The magnetohydrodynamic form of the two-dimensional Reynolds equation is derived and solved numerically for the pressure distribution. The load-carrying capacity and torque are determined from the pressure distribution. Numerical data for nonconducting bearing surfaces are compared with the data from the ordinary journal bearing. It is shown that the load-carrying capacity and torque are increased by the application of the magnetic field.


1962 ◽  
Vol 84 (1) ◽  
pp. 197-202 ◽  
Author(s):  
William T. Snyder

An analysis is presented of the slider bearing using an electrically conducting lubricant, such as a liquid metal, in the presence of a magnetic field. The solution permits the calculation of the load-carrying capacity of the bearing. A comparison is made with the classical slider bearing solution. It is shown that the load capacity of the bearing depends on the electromagnetic boundary conditions entering through the conductivity of the bearing surfaces. Numerical data are presented for nonconducting surfaces with the emphasis on a comparison between the classical bearing and the magnetohydrodynamic bearing characteristics. It is shown that a significant increase in load capacity is possible with liquid metal lubricants in the presence of a magnetic field.


2019 ◽  
Vol 895 ◽  
pp. 152-157 ◽  
Author(s):  
B. Narasimha Rao ◽  
A. Seshadri Sekhar

Magneto Rheological (MR) fluids are a class of smart materials where the shear stress is not directly proportional to rate of shear. The viscosity of fluid changes as magnetic field changes and hence this phenomenon is very useful in bearing-rotor system for attenuating the vibrations. In the present study the application of MR fluid as lubricant instead of Newtonian fluid in the journal bearing is explored through steady state, dynamic characteristics and stability. MR fluid film has been modeled as per Bingham rheological model. FEM with three node triangular elements has been used to solve the Reynolds equation both for the Newtonian fluid film and MR fluid film. The results show the load carrying capacity in the case of MR fluid journal bearing is higher than that of using the Newtonian fluid. The load carrying capacity increases with the increasing magnetic field for all eccentricity ratios. The results also show better stability of the bearing using MR fluid at higher eccentricity ratios. The unbalance response of the rotor mounted on the journal bearing using MR fluid is also estimated to be lower than that of with the Newtonian fluid.


1969 ◽  
Vol 91 (1) ◽  
pp. 199-202
Author(s):  
M. V. Korovchinski

The behavior of an infinitely long journal bearing using an ionized gas lubricant in which a magnetic field is applied axially and an electric field is applied transversely to the fluid film is investigated theoretically. It is found that in the absence of an applied electric field the behavior of the bearing with the ionized gas is not much different from that of a bearing using a neutral gas even at large Hartmann numbers. However, by application of the crossed magnetic and electric fields the pressure distribution in the lubricating film can be altered significantly. Various curves showing the effect of the Hartmann, Hughes, and Harrison numbers on the pressure distribution, film load-carrying capacity, and the locus of the journal center in the bearing are presented and discussed.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Ramesh B. Kudenatti ◽  
Shalini M. Patil ◽  
P. A. Dinesh ◽  
C. V. Vinay

This paper theoretically examines the combined effects of surface roughness and magnetic field between two rectangular parallel plates of which the upper plate has roughness structure and the lower plate has porous material in the presence of transverse magnetic field. The lubricating fluid in the film region is assumed to be Newtonian fluid (linearly viscous and incompressible fluid). This model consists of mathematical formulation of the problem with appropriate boundary conditions and solution numerically by finite difference based multigrid method. The generalized average modified Reynolds equation is derived for longitudinal roughness using Christensen’s stochastic theory which assumes that the height of the roughness asperity is of the same order as the mean separation between the plates. We obtain the bearing characteristics such as pressure distribution and load carrying capacity for various values of roughness, Hartmann number, and permeability parameters. It is observed that the pressure distribution and load carrying capacity were found to be more pronounced for increasing values of roughness parameter and Hartmann number; whereas these are found to be decreasing for increasing permeability compared to their corresponding classical cases. The physical reasons for these characters are discussed in detail.


1969 ◽  
Vol 91 (3) ◽  
pp. 380-386 ◽  
Author(s):  
S. Kamiyama

A theoretical analysis of an infinite full journal bearing is presented for the case of an electrically conducting fluid in the presence of a radial magnetic field. The analysis is based on general external loading conditions. The pressure distribution is obtained under the Reynolds’ boundary conditions in which the cavitation occurrence in the low-pressure region is taken into account. The characteristics of the magnetohydrodynamic journal bearing, namely, load-carrying capacity, altitude angle, and journal driving torque are determined. Furthermore the influence of the wall properties on the load capacity is clearly shown.


1988 ◽  
Vol 110 (2) ◽  
pp. 375-377 ◽  
Author(s):  
E. A. Hamza

The motion of an electrically conducting fluid film squeezed between two parallel disks in the presence of a magnetic field applied perpendicular to the disks is studied. Analytic solutions through use of a regular perturbation scheme are obtained. The results show that the electromagnetic forces increase the load carrying capacity considerably.


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