| The variables represented are as follows. Transmissibility: A non-dimensional ratio of the amplitude of the response of an isolation system in steady state forced vibration to the input of that system. Natural Frequency: The rate at which the system would naturally vibrate expressed in Hz (Hertz) if set into motion and allowed to continue in motion without outside interference. The primary factor determining the natural frequency of any isolation system is the load/deflection characteristic (or spring rate) of the deflectable element chosen for the isolator. The value for the natural frequency of the illustrated system is given by: 1/(2Tf )Vg/K. Forcing Frequency: The frequency (Hz) at which an externally applied excitation or "disturbance" is applied. The forcing frequency is also sometimes referred to as the "disturbing frequency". Forcing to Natural Frequency Ratio: The product of an externally applied excitation (Forcing Frequency in Hz), divided by the system's natural frequency in Hz. Resonance: A condition where the natural frequency of the isolation system and the forcing frequency match. This causes a resonant condition which is very detrimental to the operation of a machine (or many machines). |