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 uorinopuot November 29, 2009 16:11

Fluid residence time

Hello,

I am modelling blood clotting in a vessel. I want to couple the residence time of the blood in my geometry with my viscosity, whose i know the formula. How can i calculate the residence time of the blood in my geometry?

I tried using a new volumetric variable and assign it to a subdomain, but i do not know wether the values i get are right.

 ghorrocks November 29, 2009 17:58

Yes, I think your approach should work. Use an additional variable with convection activated (but not diffusivity) and put a source term on it to increase its value by the timestep size each time step.

Quote:
 but i do not know wether the values i get are right
Well, you are going to have to work that one out. How do we know if your values are right?

 kingjewel1 November 30, 2009 05:53

Quote:
 Originally Posted by uorinopuot (Post 238096) Hello, I am modelling blood clotting in a vessel. I want to couple the residence time of the blood in my geometry with my viscosity, whose i know the formula. How can i calculate the residence time of the blood in my geometry? I tried using a new volumetric variable and assign it to a subdomain, but i do not know wether the values i get are right.
Could you use particle pathlines to do this?

 ghorrocks November 30, 2009 17:29

If you want to link the fluid residence time to viscosity the additional variable approach is much easier. It is tricky to do this with particles..... but not impossible.

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