PSD Profile Random Vibration.



This program calculate the equavalent GRMS value of a random vibration profile

Calculation Reference
Random Vibration
Power Spectral Density

Equivalent GRMS (G root mean square) value is a way to express the overall energy or severity of a random vibration profile. It represents the square root of the average of the squared acceleration values over a specified frequency range. GRMS is commonly used to compare different random vibration profiles or to simplify the random vibration data into a single value for test or analysis purposes.

To calculate the equivalent GRMS value of a random vibration profile, you need to have the power spectral density (PSD) curve, which describes the intensity of the random vibration as a function of frequency. The PSD curve is usually given in units of g²/Hz, where 'g' represents the acceleration due to gravity.

Here are the steps to calculate the equivalent GRMS value from a random vibration profile:

  1. Integrate the PSD curve over the specified frequency range: Calculate the area under the PSD curve within the frequency range of interest by integrating the curve with respect to frequency. The result will be in units of g².

  2. Take the square root of the integrated value: Find the square root of the integrated value obtained in the previous step. The result will be the equivalent GRMS value, expressed in units of 'g'.

The equivalent GRMS value is useful for simplifying random vibration profiles and comparing the overall energy of different random vibration events. It can also be used to design and evaluate test procedures, such as those used in the automotive, aerospace, and electronics industries, to ensure that products can withstand the expected random vibrations during their service life.

Calculation Preview

14 Jan 2014
Last Modified
24 Apr 2023
File Size:
109.50 Kb
File Version:
File Author:
Javid Messian

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Comments: 1
JohnDoyle[Admin] 10 years ago
I have awarded a free 3 month XLC Pro subscription by way of thanks.