Discussion Forum

The system describes capillary flow up a microchannel.

Everything seems to be working fine until I increase the max time bound to 5 seconds instead of 0.3 seconds, at which point I get an inconsistent initial conditions error and an error about producing complex numbers. Is there something I can do to the time step function or maybe use a different scheme to solve it? I'm at a loss for what I can do to solve the system for anything longer than 0.3 seconds. I was thinking of successively solving my system by saving the state of the system every 0.3 seconds and loading that into the next simulation, but I don't know how to do that and it also seems like an unnecessarily long process.

Also, isn't there a way to adaptively change the step size? I learned about this in my undergrad with dormand-prince, but using dormand-prince for my solver gives me different kinds of errors and those have also led to dead ends.

Thanks,

Rick P.