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Picking up from NMech's answer: For the step response, integration constants can be expressed in terms of $\zeta$ and $\omega_0$ According to swarthmore.edu Where $\omega_0 = \sqrt{\omega_1\omega_2}$ with $(\omega_1,\omega_2)$ being the two characteristic frequencies, and $K$ is the step amplitude After that, I believe $\zeta$ can be extracted from any two ...


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The logarithmic decrement is not applicable to the overdamped systems because there are no oscillations. Also, there is not (at least to my knowledge) an equivalent to the logarithmic decrement approach to calculate the damping ratio $\zeta$ for overdamped systems. Free vibration measurement As AJN proposed what you can do is given the equation that ...


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In the analysis you are referring to the authors are only concerned about the amplification of the excitation force (they are not concerned about the total force). I.e. they only care about the additional force that the excitation is causing on the supports. (keep in mind that the vibration would still occur even in a zero-g environment if you added a ...


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Monitoring has been continuous for over 30 years in critical equipment in petrochemicals. Our rotating machinery guy liked to do it in two directions; Something about rotor swirl which helped him to predict. There must be substantial info some where .


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I know of no global standards for vibration monitoring. Like all preventive/predictive maintenance items, these things need to be equipment-specific. These are the same considerations you would apply to any preventive checks, including autonomous maintenance checks. Considerations include: process impacts (Loss of production) equipment failure cost ...


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If this is still an issue, I believe the reason for this is that the computer monitor displays the peak-to-peak value and the direct measurement displays the RMS value. 2.5 mm/s (peak-peak) = ±1.25 mm/s (0-peak) RMS(1.25) = 1.25/sqrt(2) = 0.88 mm/s That is, 2.5 mm/s peak-peak = 0.88 mm/s rms. The difference between this 0.88 and the 0.78 is probably due to ...


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