3. Types of Damping
1) Viscous damping
2) Coulomb or dry friction damping
3) Material or solid or hysteretic damping
4) Magnetic damping
4. Viscous damping
It is the dissipation of energy that due to
the movement of bodies in a fluid
medium.
5. Coulomb damping
♦ The damping force is constant in
magnitude but opposite in direction to that
of the motion of the vibrating body.
♦ It is caused by friction between rubbing
surfaces that are either dry or have
insufficient lubrication.
6. The Structural (Hysteresis)
Damping
The damping caused by the friction
between the internal
planes that slip or slide as the material
deforms is called hysteresis
(or solid or structural) damping .
7. ♦ The structural damping is caused by
Coulomb friction at a structural joint. It
depends on many factors such as joint
forces or surface properties
8. Magnetic Damping
Energy of motion is converted to heat by
way of electric eddy currents induced in
either a coil or an aluminum plate (attached
to the oscillating object) that passes between
the poles of a magnet.