Transient1
Mechanical
- Jan 31, 2007
- 267
My modal analysis indicates participation factors of less that .01 for X,Y,X-rotation and Z directions. It has a participation factor for the first mode of .37 in the Z-rotation and -.41 for the 3rd mode in the Y-rotation.
The first three modes are 919 Hz,1042 Hz,1562 Hz.
The Sine sweep does not show these resonances, but shows resonances at about 400-600 Hz depending on which axis is being monitored. Of course, some of my modeling assumptions could be wrong or my mesh not refined enough (which I don't think is the issue). My question is, if in the range of interest there are only dominant rotational modes, how do they present themselves in a sine sweep X,Y,Z axis response graph. Is there some constitutive relationship between the resonance peak in three axes that would add up to the modal analysis results?
What would be a good reference for vibration FEA? Is there any book that clearly spells out the do's and do nots of such an anlysis?
The first three modes are 919 Hz,1042 Hz,1562 Hz.
The Sine sweep does not show these resonances, but shows resonances at about 400-600 Hz depending on which axis is being monitored. Of course, some of my modeling assumptions could be wrong or my mesh not refined enough (which I don't think is the issue). My question is, if in the range of interest there are only dominant rotational modes, how do they present themselves in a sine sweep X,Y,Z axis response graph. Is there some constitutive relationship between the resonance peak in three axes that would add up to the modal analysis results?
What would be a good reference for vibration FEA? Is there any book that clearly spells out the do's and do nots of such an anlysis?