40818
Aerospace
- Sep 6, 2005
- 459
Thought i'd post in this forum rather than in the FE one.
Does anyone have any decent references which help with the determination of a local or global normal mode.
Apart from looking visually at the deformed shape, strain energy and the percentage modal effective mass fraction.
Oh, and anybody know at what percentage level the modal effective mass fraction changes from a local to a global normal mode??
I have seen documents that use ranges from 2% up to 10% but with little or no theory behind the transition point.
Any ideas?
Does anyone have any decent references which help with the determination of a local or global normal mode.
Apart from looking visually at the deformed shape, strain energy and the percentage modal effective mass fraction.
Oh, and anybody know at what percentage level the modal effective mass fraction changes from a local to a global normal mode??
I have seen documents that use ranges from 2% up to 10% but with little or no theory behind the transition point.
Any ideas?