[drvincentip]

Hi All,

I'm a beginner in learning how to use CFD model in doing hemodynamic analysis.
What I am doing is trying to convert the vessel geometry to CFD for analysis.
I'm using VMTK to extract the vessel geometry from MRA DICOM images and then export it to STL format.

I'm then stuck at this point as I don't know what to do next.
I'm using ANSYS 14.0 and I am able to import the geometry from the STL file I created in ICEM. But I don't know what to do afterwards?

Anyone help?

Thanks,
Vincent

[Ahmed]

Are you a medical student, bio-medical (mechanics) or mechanical engineering student?
That will not change the answer, but will define what language to use.
Blood pressure drop has generally been modeled as some sort of Poiseuille flow in Pipes, so what you need to do is to use ICEM to mesh the inside of the blood vessel, define an inlet and outlet/s boundary conditions (The walls of the vessel are defined as walls by default) then start the analysis Using ANSYS.
If what I wrote is not enough to help you, then I suggest to post again on The Ansys forum and attach an image of your domain or mesh that the fellows there can feel attracted to solve your problem
Good Luck

You can also read the tutorials of ANSYS

[drvincentip]

Thanks Ahmed,
I'm a Neurology Specialist and doing research in CFD now.
I understand what you said and I think my problem is I don't know how to use ICEM to define the different boundaries.
Do you have any good books or tutorials to recommend??

Thanks!

[Ahmed]

Originally Posted by drvincentip

Thanks Ahmed,
I'm a Neurology Specialist and doing research in CFD now.
I understand what you said and I think my problem is I don't know how to use ICEM to define the different boundaries.
Do you have any good books or tutorials to recommend??

Thanks!

That is what I thought (The dr at the beginning of your screen name and the terminology used in your post) anyway, here is my sincere answer:-
1- Glad to know a Neurologist that loves/likes mathematics
2- Defining a Boundary in ICEM or any other mesh generator is a two step procedure

2.1 - collecting the area you want to define as boundary and defining it as a surface (Not needed for the walls, wall boundaries are the default value)
2.2 - Giving a name/tag to that surface.

When the mesh file is read into the solver, you would be able to assign the numerical values, in your case the inlet boundary would be given a constant inlet mass flow. The outlet boundary is already defined by the solver.
3- I guess what you need is some kind of a step by step tutorials,

3-1 Start by reading this,
http://www.vmtk.org/Tutorials/CenterlinesGmsh/
3-2 Read the first tutorials that come with ICEM (personally I never liked this programme, if you can, try using Gambit, it is more humane)
3-3 If you are doing your research at a university, then it might be a good time to reach their mechanical/aeronautical engineering departments and seek the help of a phd student/smart undergrad
Good luck

[diamondx]

Originally Posted by drvincentip

Thanks Ahmed,
I'm a Neurology Specialist and doing research in CFD now.
I understand what you said and I think my problem is I don't know how to use ICEM to define the different boundaries.
Do you have any good books or tutorials to recommend??

Thanks!

When you start icem, it shows you a customer number. use it to get an account in their customer portal. you will get access to a variety of tutorial and traning material... there is a sticky thread in this section of the forum, it gives a link to a very useful channel in youtube when you see meshing techniques...

[Far]

There is example on medical flow analysis and handling STL geometry in ICEM help files installed in your computer. Take a look on it.

[drvincentip]

Thank you very much! I found the tutorial in the help menu and I'll study it.
You guys rock!!!!