If you use (1) to do the initialization, the pressure and velocities in the domain will be uniform. Supplying a restart file, the initial pressure and velocity are the same as the pressure and velocity in the restart file. Generally, for rigid simulations, initial values are not important. The resul...

Here is a part of histor.dat file. Eq N-i T dB Ri/R0 R/Ri lsIt dB %t ---------------------------------------------------------- FS 1-1 1.9970 [ 0 1.00000 6.53E-3] [ 6 -8 21] MS 1-1 2.1150 [ 0 1.00000 0.00000] [ 0 0 0] FS 1-2 3.8709 [ -15 1.59E-1 6.07E-3] [ 5 -9 10] MS 1-2 3.9870 [ 0 1.00000 0.00000]...

The inlet profile prescribed by bct.dat file should give zero velocity in the non-axial direction. In the domain, probably you won't get 0.0 exactly. 1e-4 doesn't seem too bad. If you want to further reduce it, you can consider extending the pipe. L~10D may not be sufficient.

I think the residual value printed in histor.dat is not exactly the same. It is a root mean square residual i.e. residual norm/sqrt(number of nodes). If interested, you can find the calculation in subroutine rstatic. If you want to non-dimensionalize the residual, you can divide it by the value at t...

Thanks for your plots. Could you please clarify the "velocity in x-dir over centerline of tube"? Is it a time-averaged or instantaneous plot? How did you define the error for pressure. If the flow is fully developed, the velocity profile should be independent of the longitudinal coordinate assuming ...

Can you tell me your mesh size and upload a plot/figure that shows the changes in your quantities of interest vs your mesh size? What are the residuals printed in histor.dat? Do they look ok? Usually it is a very difficult quantity for WSS to reach satisfactory convergence with pulsatile flow with a...

Yes, you can specify flow rates directly without integration. In user.f, the intent for x is INTENT(INOUT). You can directly update x and pass the value out and set the derivative f=0.

I assume the circuit you drew in the upstream of the 3D model is a resistor and the pressure distal to the resistor is P_d. At the bifurcation, you have Q_in=Q_1+Q_2, where Q_1 and Q_2 are the flow to the upstream resistor and the 3D model respectively. The pressure at the bifurcation is equal to th...

If your simulation is interrupted, generally the solver will check numstart.dat file and restart the simulation from the time step shown in numstart.dat. For example, if you start a simulation with 8 processors with restart files saved every 50 time steps and the simulation is interrupted at t=120 t...

If I understand correctly, you plan to use an RLC model to represent the domain between the CFD model outlets and the point with a known pressure. You need to implement a user-defined lumped parameter model linked to the 3D domain using GenBC in Simvascular. I am not sure if it is better than an RCR...