simtk.org

Greetings,
Someone can explain to me how the "Measure of the nonlinear residual " ( third column in histor.dat file ) and "Logarithm of the residual changeis" (fourth column) are computed?

thx
Mattia

Hi Mattia,

The Measure of the nonlinear residual is computed by substituting in the current solution for velocity and pressure into the Navier-Stokes equations. The non-linear residual that is reported in the histor.dat file is an average residual for the entire domain; the residual divided by the number of nodes in the mesh.

The Logarithm of the residual change is computed as 10*log10(Ri/R1), where Ri and R1 is the L^2 norm of the residual vectors at iteration i and 1 respectively for each time step.

These values are computed in subroutine rstatic() in here https://github.com/SimVascular/svSolver ... routines.f

Cheers,
Dave

Hi Dave,
Thank you

Mattia