Did you also use the resistance BC for other CFD software packages? You can start with a zero pressure BC for all software packages you want to compare as the baseline. Then consider comparing resistance or RCR. For commercial CFD software packages, did you use a UDF function to implement the resist...

Maybe you can do it in the post-processing. Since the wall nodal velocity is available, apply the membrane linear constitutive relationship to get the wall stress tensor: \sigma=C:\epsilon, where C is the material stiffness tensor and \epsilon is the strain rate tensor. See eqns 32-35 in Figueroa et...

For the resistance BC, we set boundary traction h=T \dot n= (-pI + \mu(\del u + \del U^T) \dot n=-p(R,Q)n=-RQn. My understanding is that the pressure=0 is not exactly satisfied if there is a perturbation in (\delU+\del U^T) even if the traction is 0. It might be more noticeable when the outflow velo...

I haven't used this in svFSI but I think you can apply the static pressure waveform as a Neumann BC at the inlet. Give it a try. In case it doesn't work, prescribing the pressure waveform via coupled BC can be considered. Here is a test case for a more complex closed-loop LPM. https://github.com/Sim...

Hi, 1. The parameters for the 3D geometry can be a resistor or an rcr or several LPMs. For example, you want to create an LPM surrogate for a 3D bifurcation model, you can choose to use 3 resistors to represent the three segments or use 2 resistors or 2 RCR models in parallel to represent the 3D mod...

When you use lumped parameter models (LPMs) to represent your 3D simulations, you have two parts: 1 the LPM for the 3D geometry 2. the LPM for the distal coronary arteries which is kept the same as the outflow BCs used in the 3D simulations. You want to identify the parameters for the 2 part to have...

Yes, using 3D simulations to tune your coronary BCs would be expensive and slow unless you know exactly which parameter should be tuned. There are numerous papers on BC tuning. An easy but effective way is to use a lumped parameter model. For example, you can use several parallel resistors to approx...

In the conventional Neumann boundary condition for the N-S equation, we specify T \cdot n=h(x,t) on the Neumann boundary \Gamma_h , where T=-pI+\mu( \nabla u +\nabla u^T). In the weak form, integrating by parts generates a term for \Gamma_h, which is -\int_{\Gamma_h}w \cdot h d\Gamma. When one wants...

For delP=0, do you mean you want to impose dP/dx=0, dP/dy=0, dP/dz=0? To my knowledge, simvascular doesn't have a way to impose this BC. Can you clarify physically what you want to impose? Simvascular solves Navier-Stokes using finite element methods. The NS eqns are written in a weak form and solve...

I feel the difference between the inflow and total outflow is more likely associated with the 3D solution strategies instead of the boundary condition. The mesh size, number of nonlinear iteration and step size have impacts on the continuity constraint. I don't think the interpolation method between...