Lubrication Investigation of a Non-Straight Internal Combustion Hydrodynamic Bearing 2009-36-0171
In order to achieve new emission regulations and customer requirements, the peak cylinder pressure (PCP) is steadily being increased and as a consequence, the loads applied on the cranktrain have increased significantly over the last decade. The higher loads have forced a complete revision of the cranktrain design affecting the design of pistons, connecting rods, and crankshafts. Consequently, the concept and performance of the related bearings have to be improved, since they are the key elements that link the cranktrain components.
The purpose of this work is to evaluate the lubrication parameters of a non-straight bearing, so called U-Shape bearing. This development presents two main challenges: one is the simulation of the lubrication parameters and the other is the achievement of an ensemble of bearing dimensions that makes the prototypes construction feasible.
Due to this particular bearing design, the commercial simulation tools do not apply. Therefore, dedicated mathematical models were developed and implemented into a computer code. By solving Reynolds equation with this newly developed computer code, it was possible to evaluate some important bearing parameters such as: peak oil film pressure (POFP) and minimum oil film thickness (MOFT). The values of these parameters were compared with the ones obtained in conventional straight bearings traditionally used in the automotive industry.