Characteristics of a Torsional Vibration Damper of Viscous-Shear Type Attatched to a Multi-Cylinder Diesel Engine

Abstract

Experimatally, we measured the torsional vibration amplitudes of a diesel generator set (4 cycle, 7 cylinders, 600 PS). Analysing 24 series of data, of different damper size and of different silicone oil viscosity, we obtained the following results : (1) It has been confirmed that the damper gives approximately a viscous damping. When the damping of enine system is properly estimated, the calculated amplitude will be practically the same as the value actually servayed. (2) We can expect a sufficient damping even when the silicone oil viscosity somewhat differs from the optimum value, since the effect of the viscosity on the amplitude is slight in the neighbourhood. (3) It is appropriate to design the damper inertia amouting to 10 to 50% of the effective inertia of the entire system.