Abstract—The performance characteristics of a thin film lubricated journal bearing are investigated by means of three-dimensional computational fluid dynamics analysis. The 3D Navier Stokes compressible equations were integrated to simulate the flow. Turbulence effects were included in the computation of unsteady transient analysis of journal bearing, taking into account gravity. The Journal bearing is designed in Gambit software, the journal is modeled as a ‘‘moving wall’’ with an absolute rotational speed of 3000rpm. The flow is simulated using Ansys Fluent software. Design parameters like relative eccentricity, dimensionless load carrying capacity, dimensionless wall shear stress, friction coefficient, Reynolds number, Sommerfeld number, strain rate, pressure distribution, temperature distribution and lubricant flow properties like turbulent viscosity, and velocity magnitude are considered for the analysis. It is assumed that the flow of lubricant is laminar and isothermal. Unsteady transient analysis is carried out for the journal bearing with different L/D ratios of 0.25, 0.5, 1, 1.5, and 2 and the corresponding results: relative eccentricity vs. Sommerfeld number, Dimensionless load carrying capacity vs. relative eccentricity, and dimensionless friction coefficient vs. relative eccentricity are presented in the analysis.
Index Terms—Eccentricity, journal bearing, load carrying capacity, turbulent dissipation rate, unsteady, wall shear stress.
Authors are with Department of Mechanical Engineering, NIT Silchar,Assam, India, (email:firstname.lastname@example.org).
Cite: K. M. Panday, P. L. Choudhury, and N. P. Kumar, "Numerical Unsteady Analysis of Thin Film Lubricated Journal Bearing," International Journal of Engineering and Technology vol. 4, no. 2, pp. 185-191, 2012.