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Natural Frequency as output parameter?

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adilch

Civil/Environmental
Joined
Apr 17, 2012
Messages
11
Location
DE
Hi all,
I am in a big trouble. As i am stuck with my research. Please help me with this problem.

I have some values of natural frequencies from a experiment on a pressure hose from lab. Now I want to validate it from Ansys model and simulation. I am able to get pretty close results from simulation and experiment.
Now I want to do Probalistic Design. Problem is this I don't know how I can set difference of resulted natural frequencies and experimental natural frequencies as my output parameter??? What is the parameter for getting the natural frequencies from ansys results??
From below code you can understand what i am trying to do.


!----------------------------------------
! sensitivity analysis
!----------------------------------------
!+++ experimental values
fe_2exp=5.54
fe_3exp=11.51
fe_4exp=21.42
fe_5exp=39.23
fe_6exp=81.14
fe_7exp=119.60

!+++ FEM result values

fe_2fem=?
fe_3fem=?
fe_4fem=?
fe_5fem=?
fe_6fem=?
fe_7fem=?

!+++ differences

P2_out= min(fe_2fem - fe_2exp)
P3_out= min(fe_3fem - fe_3exp)
P4_out= min(fe_4fem - fe_4exp)
P5_out= min(fe_5fem - fe_5exp)
P6_out= min(fe_6fem - fe_6exp)
P7_out= min(fe_7fem - fe_7exp)

I do not know to get values marked as '?'. Please help me with this :( Thanks
 
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