negative volume Flow rate
Saludos,
I have a problem with my simulation Standings and is giving me a negative volume Flow rate
Does anyone know why this happens?
thanks
Fernando Bernal
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Re: negative volume Flow rate
Normally the direction of the flow is indicated by the sign, relative to the reference axis. So, my guess is that would indicate flow in the negative X direction.
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Re: negative volume Flow rate
into the computational domain = positive
out of the computional domain = negative
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Re: negative volume Flow rate
thanks for reply, the problem was with a goal GG Mass Flow Rate, which stopped the simulation at a very small value of airflow
Muchas gracias y saludos
Fernando Bernal
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Re: negative volume Flow rate
Hi Fernado, that one sounds like a different issue. Maybe another posting? When you have a chance, can you note this one as answered? Thanks!
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Re: negative volume Flow rate
Hello
I was also searching for answer on this topic. I agree to disagree with Jared.
After testing Jared answer
"into the computational domain = positive"
"out of the computional domain = negative"
I understand now that this is not true! Because either you look for results in computational domain or not, mass flow is always negative. You can test this easily, just extend computational domain and re-run simulation.
I found in SolidWorks knowledge base 100% accurate answer:
S-022094
"Mass entering a system is positive and mass leaving a system is negative."
(System, not computational domain!)
Regards,
Ivan
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Re: negative volume Flow rate
i should note that people should be careful about this because things like porous mediums or fans can be counter intuitive, you have to consider what the system is
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Re: negative volume Flow rate
I've been confused by this issue in the past too, because when I pick an arbitrary surface that is completely enclosed by the domain, the volume and mass flow rates are almost always negative. I had always just assumed it had to do with the direction of flow and the normal vector of the surface.
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