Hi,
I am trying to model endovascular ablation. I checked the video tutorial on tumor ablation, and used some tips from it, but in my case, I also have a laminar (blood) flow within the vessel.
My domains are very simple, a tube to model the vessel, with a spherical electrode in it, all surrounded by tissue.
I tried with Electric Current + Bioheat transfer (which has heat transfer in solids and in fluids) and I get a meaningful result, however this way I won't get the velocity and pressure pattern within the vessel. Adding Laminar Flow as a third physics for some reason does not work, it won't converge to a solution.
So I tried replacing the Bioheat transfer with Conjugated Heat Transfer (default model: Heat Transfer in Biological Tissue).
I added a Fluid, with viscous heating, an inlet (value of velocity) and outlet (no viscous pressure) on the artery, and an initial value of (laminar) velocity for the vessel (and 0 velocity in the tissue). I have also tried 0 velocity for all domains. Either way I get the same error (reported below).
For the Heat Source, I chose Total Power Dissipation Density on the whole domain except the electrode, which I set as "Heat Transfer in Solids".
The Electric Current is Stationary, while the Conjugated Heat is of course time dependent.
This is all identical to what I did for the Bioheat.
But for some reason the Conjugated Heat does not converge to a solution, and I get the error
"Repeated error test failures. May have reached a singularity.
Time : 0
Last time step is not converged."
If I disable the Fluid, then I get a solution, but since I need the velocity profile, I have to keep it enabled.
I can't really understand what I do wrong with the Fluid.
If anyone has any idea, I would greatly appreciate.
Thanks so much in advance!
Rossana
I am trying to model endovascular ablation. I checked the video tutorial on tumor ablation, and used some tips from it, but in my case, I also have a laminar (blood) flow within the vessel.
My domains are very simple, a tube to model the vessel, with a spherical electrode in it, all surrounded by tissue.
I tried with Electric Current + Bioheat transfer (which has heat transfer in solids and in fluids) and I get a meaningful result, however this way I won't get the velocity and pressure pattern within the vessel. Adding Laminar Flow as a third physics for some reason does not work, it won't converge to a solution.
So I tried replacing the Bioheat transfer with Conjugated Heat Transfer (default model: Heat Transfer in Biological Tissue).
I added a Fluid, with viscous heating, an inlet (value of velocity) and outlet (no viscous pressure) on the artery, and an initial value of (laminar) velocity for the vessel (and 0 velocity in the tissue). I have also tried 0 velocity for all domains. Either way I get the same error (reported below).
For the Heat Source, I chose Total Power Dissipation Density on the whole domain except the electrode, which I set as "Heat Transfer in Solids".
The Electric Current is Stationary, while the Conjugated Heat is of course time dependent.
This is all identical to what I did for the Bioheat.
But for some reason the Conjugated Heat does not converge to a solution, and I get the error
"Repeated error test failures. May have reached a singularity.
Time : 0
Last time step is not converged."
If I disable the Fluid, then I get a solution, but since I need the velocity profile, I have to keep it enabled.
I can't really understand what I do wrong with the Fluid.
If anyone has any idea, I would greatly appreciate.
Thanks so much in advance!
Rossana