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How to set a time varying velocity field as a BC?

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Old   March 16, 2009, 08:10
Default How to set a time varying velocity field as a BC?
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Nabil
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Hello,

I'm trying to simulate blood flow in a arterie and i want to set the pulsating velocity as a boundary condition at the inlet. As i'm new to OpenFOAM and my C++ knowledge is limited at best, i was hoping that somebody here could point me to the right direction.

I was thinking of using the timevaryinguniformfixedvalue, and read from a file, like "inlet.dat" or smth like that. however I'm not sure on how to make it read a field for each timestep, instead of a vector, so any help in that department is really appreciated.

Thanks in advance.
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Old   March 16, 2009, 08:28
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Jose Luis Santos
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Hi,

I think this might help you:

http://openfoamwiki.net/index.php/OscillatingFixedValue

Regards,
Jose Santos
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Old   March 16, 2009, 09:39
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Quote:
Originally Posted by santos View Post
Hi,

I think this might help you:

http://openfoamwiki.net/index.php/OscillatingFixedValue

Regards,
Jose Santos
I thought about oscillating fixed value before, but i want to use the womersley solution to describe the velocity (heart rate) and i'm not sure i can do that using oscillatingfixed value (i figured that i would need to edit the oscillatingfixedvalue.c file to use the womersley eq instead of the one thats used), so i descided to write a small application that would give me the velocity field for a number of timesteps and output it in a file instead. And that is why i was wondering how, or perhaps even If, i could use timevaryinguniformfixedvalue.
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Old   March 17, 2009, 11:13
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Hi Mikro,

I am also calculating blood flow in arterie.

I wonder which viscosity model do you use?

Regards,
Chris
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Old   March 17, 2009, 13:57
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If you want the timeVaringUniformFixedValue, then check this thread:

Transient boundary conditions

and for the file format:

Transient boundary conditions

Dragos
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Old   March 19, 2009, 05:38
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Quote:
Originally Posted by chris_sev View Post
Hi Mikro,

I am also calculating blood flow in arterie.

I wonder which viscosity model do you use?

Regards,
Chris
I plan to use several and compare the diffrences, however i'm setting upp a newotonian case first, and right now the inlett velocity is giving me a pain in the ***...
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