Analysis of the Influence of Crankshaft System Vibrations on the Crankshaft Bending Stresses in a V-10 Diesel Engine. 2nd Report. Crankshaft Stresses Induced by Gyroscopic Vibrations of the Crankshaft System.

Abstract

The three-dimensional vibrations of a crankshat system were calculated using the dynamic stiffness matrix method taking into account gyroscopic effects. The dynamic bending stresses at fillets of the No.1 crank journal and the No.1 crank pin were measured. From the experimental and calculated results we found that: (1) the maximum bending stresses are caused by bending vibrations coupled with torsional vibrations, and the second largest bending stresses are induced by bending vibrations caused by the mass-elastic system of the torsional damper about the axis orthogonal to the No.1 crank throw plane and by gyroscopic vibrations of the inertia ring of the torsional damper; (2) forward whirl and reverse whirl of the crankshaft are induced in a crankshaft system with gyroscopic vibrations. With forward whirl, the center of the crankshaft front end traces an elliptical locus in the same direction as that of crankshaft rotation, whereas the direction is reversed with reverse whirl.