[ESPResSo-users] Particle in Fluid, periodic boundary conditions

[Wink, Markus]

Hello everybody,

 

I performed a simple simulation of a particle in a LB fluid. While checking the trajectory of the particle, I noticed a strange behavior. So I put the particle close to the wall and I see a movement towards the middle of the channel. This is expected due to the lift force. Nevertheless, I notice a break-in of the z-component, whenever the particle reaches the end of the microchannel (at position 100). So every time the periodic boundary condition takes place for the particle, I notice that behavior. Does anyone of you noticed the same behavior and can explain it to me? It seems, that the periodic boundary condition in the LB Fluid doesn’t work. If I remove the fluid I don’t see that.

 

Can anyone help me with that? Attached you will find the script as well as a figure, showing the z-coordinate as function of the position of the particle (the x-component seems to be fine).

 

Greetings

 

Markus

 

boundaries.tcl
Description: boundaries.tcl

periodic_LB.tcl
Description: periodic_LB.tcl

trajectory_raw.png
Description: trajectory_raw.png