Relation Between Noise and Basic Structural Vibration of Diesel Engines

This paper describes the relation between the diesel engine structure design, its characteristics of vibration, and emitted noise. Special techniques developed for the investigation of the origins of noise and modes of vibration are discussed. On in-line engines the effect on noise and vibration of various design alternatives, such as wet and dry-liner, underslung crankshaft and skirted crankcases, intermains and without intermains crankshaft, designs, engine size, and number of cylinders are explored.

On vee engines the origins of noise and the basic modes of vibration are established and the significance of the contribution of noise by covers is shown.

A new form of in-line engine structure design has been investigated giving 10 dbA overall reduction of noise.