Shock Pulse -Equivalent Static load for FEA
Shock Pulse -Equivalent Static load for FEA
(OP)
Hi,
Shock testing (such as MIL-STD-810)normally involves applying an acceleration over a short time interval (example: 40g over 10 ms or something like that).
If you have access to basic FEA software, this can be applied as an equivalent static G load but it doesn't consider the dynamics.
Does anyone know how to make use of the shock amplification factor (assuming I can find natural frequencies of the structure using the same FEA software)to arrive at a reasonable estimate for the G load for a static analysis ??
Any simple example would be highly appreciated.
thank you,
DonkeyDude
Shock testing (such as MIL-STD-810)normally involves applying an acceleration over a short time interval (example: 40g over 10 ms or something like that).
If you have access to basic FEA software, this can be applied as an equivalent static G load but it doesn't consider the dynamics.
Does anyone know how to make use of the shock amplification factor (assuming I can find natural frequencies of the structure using the same FEA software)to arrive at a reasonable estimate for the G load for a static analysis ??
Any simple example would be highly appreciated.
thank you,
DonkeyDude





RE: Shock Pulse -Equivalent Static load for FEA
I am also pretty certain much of the details you will need are classified (you should be carfull about your examples). Although it has been a while since I left that world.
RE: Shock Pulse -Equivalent Static load for FEA
Oh really.
DonkeyDude-you'll find a lot of threads on this in the acoustics/vibration forum. Have a read of them. I am 99% sure that Harris Handbook of vibration includes the very graph you need.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Shock Pulse -Equivalent Static load for FEA
Has the most complete discussion of your problem I've seen, but keep in mind that it assumes a single degree of freedom system undamped.