Page 5 - Vibrations
P. 5
Bearings are much better than they used to be !
In this module we shall be looking at the nature of
vibrations in devices with moving parts (machines).
A vibration is the displacement of a mass from its normal
resting position and then recovering to its resting
position.
Simple Harmonic Motion
The basic model for vibrations.
A mass m is attached to a spring
of stiffness k.
The mass is displaced and
released.
It oscillates and the varying
distance it oscillates is x.
The restoring force on the mass
once it has been displaced a
distance x is
= −
However force is related to acceleration,
2
=
2
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