What are the methods for minimising resonance??
What are the methods for minimising resonance??
How to Avoid Resonance As we’ve seen, resonance occurs when the natural frequency of a system coincides with any expected forced vibration frequencies (such as unbalance) which can lead to severe levels of vibration. If it is determined that resonance is in fact the cause of excessive vibration, what can be done to stop or minimize the effect of a resonant condition?
The natural frequency of a system is dependent upon two main factors; stiffness, and mass. If the natural frequency is w, w = sqrt(k/m).
Where k is the stiffness and m is the mass. Therefore, in order to change the natural frequency, we need to change either k or m or both. Typically, the objective is to increase the natural frequency such that it is above any expected vibration frequencies. If the natural frequency is above or significantly far away from any expected vibration frequencies the resonance will likely no be excited. This theory forms the basis for any structural redesigns implemented to avoid resonance.
In practice, the following rules can be used to shift a natural frequency and minimize the vibration response of a system;
- Adding stiffness increases the natural frequency
- Adding mass decreases the natural frequency
- Increasing damping reduces the peak response but widens the response range
- Decreasing damping increases the peak response but narrows the response range
- Reducing forcing amplitudes reduces response at resonance
As we’ve seen, resonance occurs when the natural frequency of a system coincides with any expected forced vibration frequencies (such as unbalance) which can lead to severe levels of vibration. If it is determined that resonance is in fact the cause of excessive vibration, what can be done to stop or minimize the effect of a resonant condition?
The natural frequency of a system is dependent upon two main factors; stiffness, and mass. If the natural frequency is w, w = sqrt(k/m).
Where k is the stiffness and m is the mass. Therefore, in order to change the natural frequency, we need to change either k or m or both. Typically, the objective is to increase the natural frequency such that it is above any expected vibration frequencies. If the natural frequency is above or significantly far away from any expected vibration frequencies the resonance will likely no be excited. This theory forms the basis for any structural redesigns implemented to avoid resonance.
In practice, the following rules can be used to shift a natural frequency and minimize the vibration response of a system;
- Adding stiffness increases the natural frequency
- Adding mass decreases the natural frequency
- Increasing damping reduces the peak response but widens the response range
- Decreasing damping increases the peak response but narrows the response range
- Reducing forcing amplitudes reduces response at resonance
