Numerical simulation of thermal deformation of a rough slider bearing and its Asperities: special reference on load generation in parallel sliders

Abstract

The present work is an attempt to analyze the influence of thermal deformation on the thermo-hydrodynamic lubrication of
infinitely long tilted pad slider rough bearings. As a consequence of heating the slider is deformed and is assumed to take a parabolic
shape. Also the asperities expand leading to smaller effective film thickness. Two different types of surface roughness are considered:
longitudinal roughness and transverse roughness. Christensen’s stochastic approach is used to derive the Reynolds-type equations.
Density and viscosity are considered to be temperature dependent. The modified Reynolds equation, momentum equation, continuity
equation and energy equation are decoupled and solved using finite difference method to yield various bearing characteristics. From
the numerical simulations it is observed that the performance of the bearing is significantly affected by the thermal deformation of the
slider and asperities and even the parallel sliders seem to carry some load.

Keywords

• Longitudinal roughness,transverse roughness,thermal deformation

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