436
M. Arif et al.
Fig. 2 Computational domain for journal bearing
shows the computation domain of journal bearing used for numerical analysis. The
hydrodynamic pressure produced in bearing was obtained with the use of Reynolds’s
equation. For incompressible and Newtonian fluid, Reynolds’s equation was derived
with neglecting inertia forces. Expressions are given in Eqs. (1) and (2) signify the
momentum in x and z directions with the same assumptions as discussed above.
d
2 u
dy 2 =
d p
μRdθ
(1)
d
2
w
dy 2 =
d p
μdz
(2)
Following boundary conditions is used for solving above equations.
z = 0, u = U z = 0, w = 0
z = h, u = −b
∂u
∂ x
z = h, w = −b
∂w
∂z
The modified Reynolds’ equation for non-wettable (slip) surface is shown below:
∂
∂ x
h
3
1 +
3b
[h + b]
∂ P
∂ x
+
∂
∂z
h
3
1 +
3b
[h + b]
∂ P
∂z
=
∂
∂ x
6μU h
1 +
b
[h + b]
(3)
M. Arif et al.
Fig. 2 Computational domain for journal bearing
shows the computation domain of journal bearing used for numerical analysis. The
hydrodynamic pressure produced in bearing was obtained with the use of Reynolds’s
equation. For incompressible and Newtonian fluid, Reynolds’s equation was derived
with neglecting inertia forces. Expressions are given in Eqs. (1) and (2) signify the
momentum in x and z directions with the same assumptions as discussed above.
d
2 u
dy 2 =
d p
μRdθ
(1)
d
2
w
dy 2 =
d p
μdz
(2)
Following boundary conditions is used for solving above equations.
z = 0, u = U z = 0, w = 0
z = h, u = −b
∂u
∂ x
z = h, w = −b
∂w
∂z
The modified Reynolds’ equation for non-wettable (slip) surface is shown below:
∂
∂ x
h
3
1 +
3b
[h + b]
∂ P
∂ x
+
∂
∂z
h
3
1 +
3b
[h + b]
∂ P
∂z
=
∂
∂ x
6μU h
1 +
b
[h + b]
(3)