Application of stabilized term in free boundary problems for optimizing bi-directional-rotation herringbone-grooved journal bearings

Abstract

• Using an artificial term in Reynolds equation helps to solve free boundary problems. • Few studies have investigated reversible rotating journal bearings. • The load capacity and side leakage of miniature RHGJBs are optimized. • Geometrical appearance of a miniature RHGJB can be effectively optimized. • The number of full-factorial tests is greatly reduced from 5 9 to 450 runs. In order to deal with the free boundary problems occurred in cavitation region, this work incorporates an artificial term in Reynolds equation to stabilize the solution. The current result shows that adding the extra term gives accurate pressure distribution and benefits the selection of the groove shape and size. In addition, this study utilizes herringbone grooves on a reversible rotating journal bearing (RHGJB) and numerically analyzes the characteristics of miniature journal bearings with an inner diameter of 0.6 mm. Miniature journal bearings are limited in that the load capacity is significantly reduced with decreased bearing size, and therefore, the performances (load capacity and side leakage) of miniature RHGJBs are optimized. The optimum geometrical appearance of miniature RHGJBs is calculated by evaluating several groove parameters. Using the Taguchi parameter design methodology greatly reduces the number of full-factorial experimental design tests required to determine the optimal design parameters of the RHGJB from 5 9 (1,953,125) to 450 runs.