Subject: Re: STRUC -Extraction of Impact force results Author: Randy Smith Date: 2002-09-25 09:56:00When performing a dynamic analysis the impact force would need to account for the static force plus the dynamic force. The dynamic force would be comprised of the added components of mass times acceleration and damping times the velocity. The static force is ok at 1 loadstep/iteration where the velocity matches at the next loadstep/iteration. That is the damping will offset the timing of the impact force. Do you have damping in your structure?
Randall Smith Manager Analytical Sales and Training Essig Research, Inc. 74 Carnegie Way Cincinnati, OH 45246 rsmith@e...
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-----Original Message----- Sent: Wednesday, September 25, 2002 5:10 AM To: xansys@yahoogroups.com
PS: Sorry that I forgot to end the previous mail properly...thanks.
Hi all,
I'm doing impact analysis of a sphere with a composite panel. I need to obtain the compressive force experienced by the panel but I've queries on how to obtain the impact force. There are some ways which I obtain:
1) Force experienced by the constraints (summation of the nodal forces) 2) Force experienced by the constraints (summation of the element forces) 3) Force experienced by the contact elements on the panel surface (but should I just choose those elements which comes into contact with the sphere?). 4) Force experienced by the panel elements on the panel surface.
>From these, I feel that the force should not be obtained using the 1st 2 methods since the panel is in dynamic motion and not stationary unless we're talking about the force experienced at maximum deflection (where the panel and sphere are stationary for a while). The movement of the panel suggest that the reaction force is not equal to the impact force. But I'm not sure if I were to get the force from the elements, which elements should I choose? Those on the surface only? Can anyone help?