Vibration and noise relationships: Some simple rules for the machinery design engineer

In a world in which the expert is king, countries become very small and communication between them becomes very difficult. This is so in the world of acoustics; symposia are divided into specialist sections, and experts only want to hear from greater experts than themselves. Unfortunately new technologies develop across such separations, and from time to time it is necessary to try to bridge the gaps in a manner which is simple enough to persuade each group to interest itself more widely. Such a technology is that of trying to design industrial machinery which, while increasing productivity, reduces its noise and minimizes deafness. Machinery noise emanates from heavy impacts between parts. The vibration which results from this is the flow of vibration into parts that can radiate efficiently; the noise radiated depends upon the magnitude and the wave form of this vibration, upon its frequency and upon the balance between the rate of radiation and the rate of absorption in the machine. The seriousness of t...