Numerical Investigation of Pressure Profile in Hydrodynamic Lubrication Thrust Bearing

Abstract

Reynolds equation is solved using finite difference method (FDM) on the surface of the tilting pad to find the pressure distribution in the lubricant oil film. Different pressure profiles with grid independence are described. The present work evaluates pressure at various locations after performing a thorough grid refinement. In recent similar works, this aspect has not been addressed. However, present study shows that it can have significant effect on the pressure profile. Results of a sector shaped pad are presented and it is shown that the maximum average value of pressure is 12% (approximately) greater than the previous results. Grid independence occurs after 24 × 24 grids. A parameter “ψ” has been proposed to provide convenient indicator of obtaining grid independent results. ψ = |(P refinedgrid − P Refrence-grid)/P refinedgrid|, ψ ≤ ε, where “ε” can be fixed to a convenient value and a constant minimum film thickness value of 75 μm is used in present study. This important parameter is highlighted in the present work; the location of the peak pressure zone in terms of (r, θ) coordinates is getting shifted by changing the grid size which will help the designer and experimentalist to conveniently determine the position of pressure measurement probe.

Experimental and Numerical Investigation of Static and Dynamic Characteristics of Bio-Oils and SAE40 in Fluid Film Journal Bearing

“…Further decreasing the mesh size from here on will only increase the burden on the computational system. As mentioned by [ 18 ], the increase in pressure is observed when the mesh refinement is carried out. An increase of approximately 30% in pressure is observed from a coarser mesh to a finer mesh.…”

“…By changing the grid size, the improvement in accuracy of the results is observed. The average value of pressure is 12% greater than the results obtained by using a coarse grid [ 18 ].…”

Hidrodinamik yağlamada kullanılan mikro-doku yüzeyler üzerinde akışkanın, diskin açısal hızının ve boşluk sayısının direnç azalmasına etkilerinin sayısal incelenmesi

“…They also witnessed that the location of the maximum pressure for the given operating conditions was almost same with the estimated value. Najar et al [9] solved Reynolds equation using finite difference method on the surface pad to determine pressure profile in the lubricant film. Their works assessed pressure at various locations.…”