6 show the film thickness distributions along the X axis in
Y¼0 plane and along the Y axis in X¼0 plane. The results for
smooth surfaces are compared with those for rough surfaces
(σ̅
¼1 105 and σ̅
¼3 105
). As shown, increasing the surface
roughness increases the film thickness. This is due to the contribution
of the asperities in carrying the contact load (which
decreases the part carried by the fluid) as well as their influence
on the flow behavior (which is accounted for by the flow factors in
the modified Reynolds equation), However, increasing the roughness
decreases the film parameter Λ which is the ratio of the
minimum film thickness to the combined surface roughness
(Λ ¼ hmin=
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
σ2
1 þσ2
2
q
Þ. This parameter is Λ¼1.3 for σ̅
¼1 105
and Λ¼0.6 for σ̅
¼3 105
.
It