[ESPResSo-users] flow profile square duct - deviation

[Wink, Markus]

Hello everybody,

 

I performed a simple simulation of a poiseuille flow in a microfluidic square duct. I wanted to check, whether the simulated profile matches with the theoretical one (I found the formula in frank M. White’s “Viscous Fluid Flow”).

 

The simulated values matches the theoretical ones quite good in the middle of the channel. Strangely enough, I have a quite big deviation close to walls of the channel (the last fluid node closest to the boundary nodes), which is even worse in the corners of the channel (about 42% deviation (!!) ). I was wondering, where this deviation comes from. Attached you will find the simulation script as well as the plots showing the deviation.

 

Does anyone have a clue, where the deviation comes from?

 

Greetings

 

Markus

 

 

boundaries.tcl
Description: boundaries.tcl

simulation.tcl
Description: simulation.tcl

plots.pdf
Description: plots.pdf