Dynamics and Lubrication Problem Analysis of Main Bearings for IC Engines Based on Coupling between a Crankshaft and a Flexible Whole Engine Block

The article presents the solution to the interconnected problem of main bearings dynamics for the forced internal combustion (IC) engine. For the crankshaft main bearings system of the (IC) engines it is necessary to consider the cross-coupling effect of the tribounits arising from elastic links of bearings and journals (by means of an engine crankcase and a crankshaft). The technique is based on the iterative scheme of the solution of four tasks given above. It analyzes not only the influence of macrogeometry parameters of each main bearing and the influence of non-Newtonian properties of lubricant, but also elastic characteristics of a crankshaft and crankcase and supports displacements caused by the thermal deformation of an engine crankcase. The influence of technological coaxiality tolerance for bearings and necks of a crankshaft is also estimated. The modeling results of two types of engines are compared to various design of a crankcase. The research shows the necessity of applying the integrated approaches which allow considering simultaneously both the features of autonomous bearings and many facts of their interaction.