1. Forces transmitted to foundations, casing, or bearing pedestals

Constant, unidirectional force

Constant force, rotational Variable, unidirectional

Impulsive forces Random forces

Constant liner acceleration Rotation in gravitational or magnetic field

Impressed cyclic ground or foundation-motion

Airblast, explosion, or earthquake

Nearby unbalanced machinery Blows, impact

1. Forces generated by rotor motion

Rotating unbalance; residual, or bent shaft Coriolis forces

Elastic hysteresis of rotor

Coulomb friction

Fluid friction

Hydrodynamic forces, static.

Hydrodynamic forces, dynamic.

Dissimilar elastic beam

Stiffness reaction forces

Gyroscopic moments

Present in all rotating machinery

Motion around curve of varying radius. Space applications

Rotary-coordinated analyses

Property of rotor material which appears when rotor is cyclically deformed in bending, torsionally or axially

Construction damping arising from relative motion between shrink-fitted assemblies

Dry-friction bearing whirl

Viscous shear of bearings

Fluid entrainment in turbomachinery

Windage

Bearing load capacity

Voute pressure forces

Bearing stiffness and damping properties

Rotors with differing rotor lateral stiffness. Slotted rotors, electrical machinery, Keyway. Abrupt speed change conditions

Significant in high-speed flexible rotors with discs

1. Applied to rotor

Drive torque

Cyclic forces

Oscillating torques

Transient torques

Heavy applied rotor force

Gravity

Magnetic field: stationary or...