Theoretically, the absolute pressure is undetermined up to a constant. The pressure map doesn't look right. You can use a coarse mesh (<1 M elements) to run 1-2 cycles and check if the inflow waveform is correctly imposed on the inlet. If there is flow streaming from the inlet to outlets, the pressu...

Assume the restart file for the last step in a rigid simulation is restart.100.0. Copy it to your current simulation dir. and rename it as restart.0.1 In your svpre file, remove "initial_pressure 0" and "initial_velocity 0.000 0.000 0.000". Rerun the presolver script in the command line by typing "s...

You should provide volumetric flow rate waveform (e.g. cm^2/s) instead of velocity waveform. Simvascular calculate the nodal velocity U(x,y,z,t) based on the volumetric flow rate waveform and the velocity profile you choose.

You can use some software to process the PCMRI data (usually in Dicom format) to obtain volumetric flow rate vs time. For example, http://medviso.com/segment/ Once you have time vs flow rate, you can copy and paste them into a text editor (e.g. vim or gedit) and save them as .flow file. Similarly, f...

If the outlet pressure and flow do not agree with the analytical solution, it seems the boundary condition is not correctly imposed. You may check the presolver script (.svpre) and the solver.inp to see if the outlet ids are tagged and listed correctly in the solver.inp. If IDs 1, 2 and 3 are assign...

What are the RCR values for the descending aorta? First I think you can verify if RCR is prescribed correctly on the outlets. For each outlet, use the outlet flow data and RCR values to calculate the analytical outlet pressure. The 3D outlet pressure should be the same as this analytical expression....

The inlet flow such as Figure 8: Aortic inflow waveform is usually obtained by PCMRI (phase contrast) that gives you flow rate vs time for a imaging plane. If you don't have your own measurements, you can obtain the inflow waveform data from some MRI studies. To plot pressure/flow vs time, you can u...

Here is a cylinder example using ALE-FSI. https://www.dropbox.com/s/tjyrzzlcb7uvm6u/cylinder_ALE_FSI.zip?dl=0 The structural domain is created by using meshmixer (extrude a fluid cylinder). By importing the wall model (stl file) back to simvascular, you can mesh the structural domain. Then use the i...

This boundary condition might not be well imposed. Under this setting, the inflow condition can fluctuate a lot if the pressure is not stable. Under converged conditions, dpdt should be very small and having a 0D-3D coupling like this might be OK. But this is not better than prescribing the inflow c...

By default, an RK4 time integration is used to integrate ODE from t to t+dt, for any time t_{0d} between t and t+dt, the 3D pressure "p" is interpolated by solutions P_n and P_{n+1}. Therefore, for each RK point, the corresponding 3D p is not exactly the same. You can find more details in another fi...