Operator‐splitting method for the analysis of cavitation in liquid‐lubricated herringbone grooved journal bearings

Abstract

SUMMARYThis paper presents an operator-splitting method (OSM) for the solution of the universal Reynolds equation. Jakobsson-Floberg-Olsson (JFO) pressure conditions are used to study cavitation in liquidlubricated journal bearings. The shear ow component of the oil ÿlm is ÿrst solved by a modiÿed upwind ÿnite di erence method. The solution of the pressure gradient ow component is computed by the Galerkin ÿnite element method. Present OSM solutions for slider bearings are in good agreement with available analytical and experimental results. OSM is then applied to herringbone grooved journal bearings. The ÿlm pressure, cavitation areas, load capacity and attitude angle are obtained with JFO pressure conditions. The calculated load capacities are in agreement with available experimental data. However, a detailed comparison of the present results with those predicted using Reynolds pressure conditions shows some di erences. The numerical results showed that the load capacity and the critical mass of the journal (linear stability indicator) are higher and the attitude angle is lower than those predicted by Reynolds pressure conditions for cases of high eccentricities.

Issues related to the numerical simulation of herringbone grooved journal bearing including cavitation condition

“…For the same operating conditions and bearing dimensions various authors have reported various values of attitude angle at the same eccentricity ratio. The difference may be because of the cavitation boundary considered, as Rao and Sawicki 12 and Jiankang et al 20 have considered non-dimensional cavitation pressure as P c = 0; and Lee et al 11 and Jang and Chang 9 have considered non-dimensional cavitation pressure are P c = −1. In the present analysis, the cavitation pressure considered is P c = 0, and the attitude angle results although not in complete agreement but are closer to Jiankang et al 20 results.…”

Leakage-free optimization of micro herringbone grooved journal bearings with a virtual node method

“…Jang and Chang (2000) analyzed the performance of a herringbone grooved journal bearing in the spindle motor of a computer hard disk drive including the effects of cavitation by using the finite volume method with mesh fitting the groove profiles. Many other references (Wu et al, 2004;Lee et al, 2004;Chao and Huang, 2005;Chen et al, 2012) also studied the lubrication performance of MHGJB by using the FDM in the non-orthogonal coordinate system with skew mesh. However, it should be pointed out that there exists some numerical singularity for the MHGJB at the critical line of two skew coordinate systems if groove fitting meshes are used, especially for the large skew angle of herringbone grooves.…”