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negative velocity inlet

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Old   July 22, 2015, 11:51
Default negative velocity inlet
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Hi,

I wrote a field function to control the inlet velocity of a boundary:

cos(${Time}*2*3.14*2)*10

It works until the velocity reaches 0 and then rises again, I never get a negative velocity at the inlet. I ran reports, which showed that the output of the field function was indeed negative, but Star CCM+ turned it into a positive value for the velocity inlet.

It seems like a velocity inlet cannot be used as an outlet by simply putting a minus in front of the value. What would you do to accomplish this?

kind regards,

hebeldebel
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Old   July 22, 2015, 17:33
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maybe try using a mass flow inlet? I know those can go negative.

honestly, this seems like a bug. you may want to submit it to CD-Adapco so they can resolve it.
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