[uorinopuot]

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]

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.

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]

Originally Posted by uorinopuot

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]

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.