1832 - EME5213 01
Dr. Ihab Grace
What is vibration?
Vibration is the oscillation of a system about an equilbrium position.
It is an everyday phenomenon we meet on everyday life.
Can an Engineer avoid vibration in his desi
Viscously Damped Free Vibration
For linear viscous damping, the damping force is linearly
proportional to the velocity
Fd c x
c is the damping coefficient, its units are
force/velocity, i.e., N.s/m, or lb.s/ft.
m cx kx
m cx kx 0
For a mass spring sing system
Kinetic energy is
Gravitational potential energy is
Elastic potential energy is
T mx 2
Vg mg ( x)
Ve k x
Applying the conservation of energy equation
T Vg Ve
0 mx 2 0 mg x mg k ( x