Study on Internal Flow Characteristics and Law of Conrod Small End Bearing for Internal Combustion Engine

This paper establishes a model of flexible multibody dynamics for conrod small end bearing based on extended Reynolds equation considering lubricating oil fill ratio and average flow model. It analyzes internal flow process and characteristics of lubricating oil, discusses oil film formation and distribution mechanism, and acquires influence law of revolving speed and modeled lines on internal flow. Results show the flow of lubricating oil in conrod small end is mainly affected by relative motion of piston pin and bushing, and further spreads circumferentially, and inhales from outside and flows out axially; with revolving speed increases, average volume flow rate is higher, and minimum oil film thickness is reduced; neither the in-cylinder pressure nor change of bushing internal surface molded line affects average volume flow rate significantly.