On the prediction of impact noise, II: Ringing noise

Abstract The introduction of legislation regarding the limits of noise in factories has led to the need for the prediction of likely noise levels produced by a machine at the design stage. Part I was concerned with the noise produced by impacting bodies due to the high surface accelerations during the contact period. Part II is concerned with the noise arising from the subsequent free vibration. The radiation efficiency of simple components having various modes of vibration is discussed and presented in the form of charts, which it is hoped will enable the machine designer to predict the ringing noise of a machine at its design stage, once the surface area and mean square surface velocity have been established.