Dillip Kumar Panigrahi
PhD Scholar
Research Area:
Thrust Pad Bearing with Surface Texture.
Surface texturing has been recognized as one of the effective means to improve tribological performance of mechanical components. This technique can have a large variety of industrial applications, such as biomechanical components, solar cells, hydrodynamic bearings, mechanical seals, piston ring, cylinder-liner contacts and magnetic media disks, etc. Under full film lubrication condition, each micro dimple of the textured surface acts as a Rayleigh step, which could develop hydrodynamic pressure and thereby, will enhance the total load carrying capacity. In this situation, pressure in the lubricant may fall below gas saturation pressure or evaporation pressure at the divergent zone (i.e., trailing edge), leading to the occurrence of cavitation. It was found from literature that higher cavitation pressure significantly alters the hydrodynamic (positive) pressure development, so as the load carrying capacity and friction parameter. Therefore, an attempt has been made to investigate the cavitation phenomenon of positive textured surfaces under full film lubrication condition on parallel thrust bearings, where the cavitation zone profile, cavitation pressure, frictional force, load carrying capacity and oil film thickness are determined both experimentally and theoretically. It is found from the experimental results that with increasing speed, both (-ve) cavitation and (+ve) hydrodynamic pressure increases which can be correlated to the observed reduction in recess pressure and increment in film thickness. On the whole, higher cavitation at the trailing edge of the textures helps and/or enhances the (+ve) hydrodynamic pressure development.
