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-   -   oscillation in steady state (http://www.cfd-online.com/Forums/cd-adapco/56757-oscillation-steady-state.html)

Arman August 8, 2008 01:30

oscillation in steady state
 
Hi,

I'm simulating a flow around a barge using steady state setting. However, when I plot the force, it oscillates (600 iterations, maybe more? But the force seems to fluctuates constantly). Does this means that I have a transient motions, e.g. vortex shedding? Or there is more to it?

Eric August 8, 2008 12:13

Re: oscillation in steady state
 
For steady cylinder flow, I know my solution is as converged as position when my residuals start oscillationing about a steady datum. For cylinder flow, that's all vortex shedding, even though I'm running steady state.

I don't know what your barge looks like, but it's not a bad first guess to think that vortex shedding could be causing that force fluctuation.

Just curious, along what line are you plotting force on the barge?

Breivik April 30, 2012 10:44

oscillation of Ct
 
Hi
I'm doing a calculation on a ship in steady state with a multi-phase VOF wave. I'm also experiencing som fluctuation in the Ct value. I don't know why this happens?
I would bemuch obliged if someone could answer this question.


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