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Transient Flow, Transient Pressure in Work Bench

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Old   May 4, 2007, 10:11
Default Transient Flow, Transient Pressure in Work Bench
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We are modeling a rotating fan that undergoes relatively large changes in pressure as it rotates. In order to get the mapping to work in the same global coordinate system in Workbench, I rotate the stationary components in Pre and set up definition files for multiple time steps/angle of rotations. When each pressure is applied at successive time steps, the Resultant loads map at 100% and appear correct. The only problem is that the stress levels gradually increase to a much higher value than predicted in the static analysis. The overall magnitude of the pressures individually would not yield such a high stress. It is as if the pressures are additive, as opposed to only applied at those time steps. Is there a CMD file in Workbench that would ensure the CFX pressures are only applied at their own individual time steps? Could there be something else?

Thanks for your help,

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Old   May 8, 2007, 11:55
Default Re: Transient Flow, Transient Pressure in Work Ben
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Our Ansys Support office gave us a work around. There are Ansys commands available to turn on and off the pressure loads at their respective time steps. Otherwise, the pressures are seen as additive...

Thanks Ansys Support!

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