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Add Axial Force Goal from previous solution

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Old   March 24, 2015, 04:35
Default Add Axial Force Goal from previous solution
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Maxime Perelli
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Hello,
I have computed one Design, and I was asked to evaluate the axial force on a piston.
I thought I could create a surface goal with axial force and run the calculation from previous converged solution with only 1 iteration, but the solver doesn t give me the possibility to continue. I can only re-compute.
Is there any workaround for computing the force without recomputing the whole stuff
Thank you
Maxime
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Old   March 24, 2015, 10:03
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Boris Marovic
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Hi Maxime,

There are two ways:

1.
Your way doesn't work because you will have to remesh in order to resolve the goal with the mesh but you can clone the project and use the goal in the second project and then set the initial conditions in the general settings not as user defined but as transferred and select the other project or its FLD file as the initial condition. Then your calculation starts from scratch but initiates with the previous results. You might get a spike at the beginning as the calculation is starting over a few iterations and it doesn't show you that it is converged until it reaches 1 travel but as soon as the fluctuations stop you should see the values stabalize at about the same value as before.

2.
And much easier method, simply use surface parameter on that body just like you would use the goal and see what the forces are.
But please consider the relative pressure for such force calculations. You might need to set it to a different value depending on the calculation results you have.
This way you don't have defined it as a goal and the calculation has converged for it but it also will not be converged for the force if you only calculate for one more iteration.

Boris
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Old   March 25, 2015, 07:21
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Maxime Perelli
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Thank you Boris
I am following your 1st point.
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