Vibration engineering
terms

 

AmplituteA[m]Distance moved by a point on a vibrating body measured from its equilibrium position. The total vibration is therefore twice the amplitude
Frequencyf[Hz]Number of oscillations in a given unit of time. Defined in cycles per second or Hz
Vibration generator frequencyf[Hz]Usually the same as the rotational speed of the machine
Natural frequencyfo[Hz]Number of oscillations of a free-running system per unit of time
Massm[kg]Mass of the vibrating system
Spring forceF[N]The resilient force transferred by a spring to a machine or vice versa
Spring excursion*[m]The deflection of a spring from a neutral position
Spring ratek[N/m]The force required to compress a vibration damper by 1m, expressed in newtons
TuningZThe ratio of vibration generator frequency f to natural frequency fo
Disturbance forceFs[N]The force transferred to the base in the case of a spring-mounted machine
Impelling forceFi[N]The total force transferred to the base in the case of a rigid-mounted machine
Amplification factorBThe degree of efficiency accompanying the transfer of the vibration force, i.e. the ratio of disturbance force Fs to impelling force Fi.
Isolation rateIThe degree of efficiency of vibration damping by means of isolation, (1-B) or, in case B, expressed as a percentage (100-B).
Damping coefficientC[Ns/m]The reference value for linear viscous damping
Critical damping coefficientCkr[Ns/m]The reference value for linear viscous damping for a critical application. A system is critically damped if it returns to its original position after displacement without overshooting displacement without overshooting
ReductionR[db]Reduction of structure-borne sound in dB.

 

EQUATIONS TAKEN AS A BASIS FOR CALCUATIONS
Input data:Gravitational acceleration g= 9.81 m/s²
Mass m [kg]
Impulse time tst [s]
Or shock class
Kinetic energy of excitation:Kinetische Energie der Anregung:
Energy absorption:Energieaufnahme
Stress analysis:Festigkeitsnachweis
Dynamic spring rate:Dynamische Federrate:
Static damper compression:Statische Einfederung
Natural frequency:Eigenfrequenz:
Residual acceleration:Restbeschleunigung
Vibration displacement amplitude:Schwingwegamplitude
Static damper compression
at prescribed
residual acceleration:
Statische Einfederung bei vorgegebener Restbeschleunigung