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This paper analyses the steady-state performance behaviour of a new type of journal bearing, i.e. the non-circular cylindrical floating ring journal bearing. It consists of a floating ring in between the shaft and the upper and lower lobes of a two-lobe bearing. The journal and the inner surface of the ring are cylindrical while bearing surfaces are non-circular. The classical Navier-Stokes equations in the modified form together with the continuity equation are being solved by the finite element method. The cylindrical coordinates form of the Navier-Stokes equation and continuity equation are used in the present analysis to compute the important proposed bearing characteristics. In this analytical study, the finite bearing approximation (L/D¼1) with a C 2 /C 1 value of 0.70 and 1.30 are being used to simulate the behaviour of non-circular cylindrical floating ring journal bearing. The Reynold's boundary condition is used to enumerate the performance of the proposed bearing. In the present analysis, the steady-state parameters in terms of an inner and outer film eccentricity ratio, a speed ratio, attitude angle, load capacity, friction coefficient parameter, axial oil flow and rise in temperature variable are determined. The results reveal that the steady-state performance of the non-circular floating ring journal bearing is superior to a plain cylindrical floating ring journal bearing.

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The present paper investigates the turbulence effect on the steady-state performance of a new variety of journal bearing, i.e. the noncircular floating ring bearing. This particular bearing consists of the journal, floating ring, as well as lower and upper lobes. The shaft and the floating ring are cylindrical while surfaces of the bearing are noncircular. The classical Navier–Stokes equations and continuity equation in cylindrical coordinates are being satisfactorily adapted with the linearized turbulent lubrication model of Ng and Pan. These improved equations are being solved by the finite element method using Galerkin’s technique and an appropriate iteration strategy. The proposed bearing has a length-to-diameter ratio of 1 and operates over different values of the ratio of clearances (i.e. 0.70 and 1.30). The steady-state performance parameters computed are presented in terms of an inner and outer film eccentricity ratios, load-carrying capacity, attitude angle, speed ratio, friction coefficient variable, oil flow, and temperature rise variable for the Reynolds number up to 9000. The present analysis predicts better performance in the turbulent regime as compared to the laminar regime for the noncircular floating ring bearing.

The performance of a noncircular cylindrical floating ring bearing under the laminar flow condition has been analyzed. The noncircular cylindrical floating ring bearing is a modified version of the plain cylindrical floating ring bearing in which the outer bearing of the cylindrical floating ring bearing is changed in the form of lobed pattern. The noncircular patterns are known for its better stability and stiffness behavior according to the magnitude of applied loads. The finite element analysis has been used to solve the classical Navier–Stokes equations in the cylindrical coordinates of the modified form along with the continuity equation that represents the fluid flow field in the clearance space of the noncircular cylindrical floating ring bearing. The numerical data are for a proposed bearing with the length to diameter ratio of 1.0, and values of the ratio of film clearances of 0.70 and 1.30. Performance characteristics of a finite noncircular cylindrical floating ring bearing has been studied in terms of the inner and outer film eccentricity ratio, Sommerfeld number, attitude angle, stiffness and damping coefficients, equivalent support stiffness coefficient, whirl frequency ratio, and critical journal mass at various values of the outer film eccentricity ratios. The proposed analysis disseminates that the dynamic performance parameters of the noncircular cylindrical floating ring bearing are much better than the plain cylindrical floating ring bearing.