N.B. Naduvinamani, Siddharam Patil and S.S. Siddapur
Nowadays, the use of Newtonian fluid as a lubricant is diminishing day by day, and the use of non-Newtonian fluids has gained importance. This paper presents an analysis of the…
Abstract
Purpose
Nowadays, the use of Newtonian fluid as a lubricant is diminishing day by day, and the use of non-Newtonian fluids has gained importance. This paper presents an analysis of the static characteristics of Rayleigh step slider bearing lubricated with non-Newtonian Rabinowitsch fluid, which has not been studied so far. The purpose of this paper is to derive the modified Reynolds equation for Rabinowitsch fluids for two regions and to obtain the optimum bearing parameters for the Rayleigh step slider bearings.
Design/methodology/approach
The governing equations relevant to the problem under consideration are derived. The modified Reynolds equation is derived, and it is found to be highly non-linear and hence small perturbation method is adopted to find solution.
Findings
From this study it is found that there is an increase in the load-carrying capacity, pressure and frictional coefficients for dilatant fluids as compared to the corresponding Newtonian case. Further, for dilatant lubricants the maximum load-carrying capacity is attained for the slightly larger values of entry region length of Rayleigh step bearing as compared to Newtonian and pseudoplastic lubricants.
Originality/value
Rabinowitsch fluid is used for the study of lubrication characteristics of Rayleigh step bearings. The author believes that the paper presents these results for the first time.
Details
Keywords
Pentyala Srinivasa Rao and Amit Kumar Rahul
This paper aims to investigate the effect of surface roughness (radial and azimuthal) and viscosity variation on a squeeze film of a conical bearing with a non-Newtonian lubricant…
Abstract
Purpose
This paper aims to investigate the effect of surface roughness (radial and azimuthal) and viscosity variation on a squeeze film of a conical bearing with a non-Newtonian lubricant by using Rabinowitsch fluid model.
Design/methodology/approach
The main objective is to determine the stochastic nonlinear modified Reynolds equation for rough conical bearing. Later, first-order closed-form solutions are obtained using a small perturbation method and are numerically solved using the Gauss quadrature method.
Findings
The findings of this paper, numerical calculations, are analyzed for pressure, load carrying capacity and response time. The simulated results indicate that the influence of surface roughness increases the pressure, load carrying capacity and response time, whereas the viscosity variation factor decreases the pressure, load and response time.
Originality/value
According to both types of surface roughness with viscosity variation, the performance of a squeeze film rough conical bearing was improved by using Rabinowitsch fluid model. As it is inevitable to consider viscosity variation for bearing designer, it leads to a long life period of conical bearing.