journals are used to support high loads high speed rotating turbo machinery elements mainly shafts and

attached components and also for enhancing the quality of these machines. In this work, the importance of

journal bearing and an overview of the Reynolds hydrodynamic equation in three dimensions have been studied

using the Boundary Value finite-difference method. The second-order nonlinear partial differential equation

has been solved using numerical iterations approach with MATLAB software. The numerical solution of the

transient Reynolds equation has been studied to investigate the Pressure distribution, pressure gradient as well

film lubricant thickness on journal bearings. A numerical solution using ANSYS FLUENT has been applied to

investigate the main parameters that have the main influence on the performance of the journal bearing and

bearing performance.

The main purpose of journal bearings is to support

rotating shafts in a large number of applications

mainly turbo machinery, crankshafts, and camshafts

applications such as in internal combustion engines,

axial flow compressors, and axial flow turbines,

[1].

between rotating and stationary elements are

governed by complex three-dimensional Nervier

stokes equations in both Cartesian cylindrical

lubricant volumetric flow rate, type of load, and

minimum film thickness, [3].

slider bearing has been used. The bearing curvature

effect has been neglected which means a plane

factors have a great effect on the journal

performance. If the eccentricity is large, there is a

metal-to-metal contact especially at high dynamic

loads causing premature fatigue, [6].

of changing . Load-carrying capacity, lubricant film

thickness, Coefficient of static and dynamic friction

factors, and Pressure distribution using a continuity

equation. The separation of variables method has

Reynolds equation have been solved using

numerical methods such as finite difference and

finite element depending on the specified special

cases of boundary conditions and geometry.

equation in one and two dimensions has been

studied for specified cases of the independent

variable. Boundary conditions that correspond to oil

film thickness for both maximum and minimum

data were specified for different independent

and stress constitutive equations. The velocity

components for the two-dimensional flow of a non-

Newtonian fluid were obtained. For different

solutions obtained, differentiation and integration

techniques have been applied for different cases of

boundary conditions they found that the

performances of journal bearings lubrication with a

non-Newtonian fluid can be compared with the case

of Newtonian lubricant through the variation of the

non-Newtonian parameter, i.e., the nonlinear

perturbation method has been proposed to find

pressure distribution through the entire length of the

bearing. Pressure coefficient, shear stress, as well as

friction factor, and fluid film pressure distribution

were calculated and analyzed as a function of

azimuthal position factor, dimensionless bearing

Somerfield number, minimum film thickness, and

eccentricity ratio .

Reynolds was restricted to incompressible fluids as

shown in Figure 1. Thus, it had been developed

generally enough to incorporate the results of

compressibility and dynamic loading and was

aforementioned to be Generalized Reynolds

Equation . So, the main form of the Generalized

Reynolds Equation was as given in three dimensions

is given by:

Fig. 1: Journal Bearing Layout

profiles (11).

Using parameters from Table 1, the pressure

function from equation 7 and the following

parameters variables: μ=0.02756 Pa .s, R=19 mm,

c=0.038, ho=0.016 mm, e=0.022 mm, Ø=53o and

angle (θ) on pressure can be obtained as illustrated

in Figure 3 and Figure 4 respectively. Figure 6

shows the relation between pressure and cleannce at

constant rotational speed. Figure 8 shows the

Figure 14, Figure 15, Figure 16 and Figure 17.

Fig. 3: pressure and rotational speed at a constant

angle

Fig. 4: pressures with the angle at constant

rotational speed

Fig. 7: The chart between pressure with Attitude

0.1%

diameter of 15 mm, and dynamic viscosity of

magnitude of [0.007 pa.s], and a radial clearance of

0.03mm as shown in Figure 13.

Fig. 13: Journal Bearing

Fig. 17: Total pressure

Journal bearings are one of the most important

applications of hydrodynamic lubricant devices, The

investigating the pressure gradient and pressure

firstly 30 elements. The pressure distribution and

comparison between the transient and steady-state

bearing performance characteristic parameters

velocity distribution, and turbulence effect, all

[12] Michael Deligant Pierre Podevin Georges

[14] Michael Degant, Pierre Podevin, George