High amplitude wave liner effects on journal bearing performance

Abstract

Modification on the liner bearing was one of the ways to achieve sufficient lubricant on a journal bearing system. Efforts had shown that the ability to retain some lubricant by introducing wave like grooves on the liner has improved the performance of the bearings. However, the database for the modifications is still lacking. This study aims to establish and correlate modifications of the liner with the performance of the journal bearing. Numerical and experimental work were done to compare and relate several geometries of liner bearing modifications based on previous studies as well as new ones. The previously studied sine wave liner bearing involved investigations with the square and semi circular liners. Plain liner bearing was used as reference. All cases were investigated experimentally by a test rig under low operating loads of 30 N to 450 N with high speed conditions of 1200 RPM to 2800 RPM. Some of the parameters were validated in order to compare the numerical and experimental data. Case studies also included engine oil and palm olein as the lubricants. The performance of the bearings was analyzed by examining the side flow rates, lubricant temperature change, eccentricity ratio, and pressure distributions. The results show that, modifying the shape liner bearing under all operating conditions could increase the lubricant flow rate which was approximately 1.5 times than the plain liner bearing and reduce the lubricant temperature change by about 35%. The bearings with the wave shape liner led to the eccentricity ratio increase but within the acceptable range of 0.6 to 0.9. Majority of the results showed lower a maximum pressure than the plain liner bearing with the exception of the bearing with the square wave shape liner.