The very rapid deceleration on impact of the platen (tup) in a drop forging machine is shown to be an important source of impulsive noise. An ‘explicit’ finite-difference method is used to calculate the sound pulse radiated by a platen in the form of a solid cylinder undergoing a deceleration given by
where T is the impact time. The results are presented in dimensionless form, enabling the pulse to be calculated for a wide range of platen sizes and impact times.
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