Three Cylinder Engine Balancing Model

This article presents the dynamic modeling of a three-cylinder engine, known in the literature for high levels of vibrations due to equilibrium conditions. The engine and gearbox assembly were modeled as a rigid element with 4 degrees of freedom (DoF), these being displacement and rotation around the X and Z axes. In the presented study, it was calculated the dynamic responses of two support cushions of the engine, having as excitation the inertial forces related to the reciprocating movement of the pistons and connecting rods, and unbalance of the crankshaft counterweights. The results obtained with the mathematical model were compared with measured data of first order vibration of the engine rotation. Tests were performed at full throttle, WOT condition, in third gear.