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KVSlab / VaMPy

A collection of tools for pre-processing, simulating, and post-processing vascular morphologies.
https://kvslab.github.io/VaMPy
GNU General Public License v3.0
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Bug in computing hemodynamic indicies #147

Open keiyamamo opened 5 months ago

keiyamamo commented 5 months ago

Same problem as https://github.com/KVSlab/VaSP/issues/157

hkjeldsberg commented 4 months ago

@keiyamamo Any updates on this? A fix for P1 elements would be of great interest!

keiyamamo commented 4 months ago

Hi @hkjeldsberg Fixing the problem of wall shear stress magnitude having negative value should be easy. You just need to replace tawss = project(inner(tau, tau) ** (1 / 2), U_b1) as follows.

https://github.com/KVSlab/VaSP/pull/160/files

This should work for P1 since we are just taking the magnitude of dofs instead of using project.

To me, the other problem is that VaSP and VaMPy produce different values. I tested VaSP implementation against analytical solution and it is integrated as pytest. Therefore, I’m pretty confident that the implantation in VaSP is correct, but I might be wrong. Additionally, the old (see below) and current implementation of wall shear stress seems different in VaMPy . Maybe they produce the same result anyway, but it is unclear why or how these changes are made.

Screenshot 2024-05-06 at 9 34 33