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Volume 15, December 2017, Pages 50-64
Effects of velocity-slip and
viscosity variation in hydrostatic step-seal
Rajarapu R. Rao
Department of Mathematics, College of Natural Sciences, Abaya Campus, Arba Minch University, Arba Minch, Ethiopia
Abstract
A generalized form of Reynolds equation for two symmetrical surfaces is
taken by considering velocity-slip at the bearing surfaces. This
equation is applied to study the effects of velocity-slip and
viscosity variation in squeeze film lubrication of hydro static
step-seal. Expressions for the load capacity are studied
theoretically for various parameters. The load capacity decreases
due to slip. The Load Capacity increases due to the presence of high
viscous layer near the surface and decreases due to low viscous
layer and it has been shown that the load capacities of squeeze film
bearings decrease and those of step seals increase with an increase
in the step height. With a hydrostatic step seal, the load capacity
increases as the flow behaviour index of the fluid increases.
Keywords
Reynolds equation; Velocity-slip; Viscosity variation; Squeeze film lubrication; Load capacity; Squeezing time
Full Text
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