Re: [ESPResSo-users] Simulation of fluid using LB-method

[Stefan Kesselheim]

Hi,
please try 
lbboundary wall normal 0 0 1 dist [expr $agrid]
lbboundary wall normal 0 0 -1 dist [expr -$l-$agrid]
Cheers
Stefan


On Jan 30, 2014, at 3:23 PM, "Wink, Markus" <address@hidden> wrote:

> Hello,
> 
> Well in the case of the a_grid=0,5 I chose in my tcl-script:
> 
> "
> set l 51.5
> setmd box_l $l $l $l
> [...]
> set agrid 0.5
> 
> lbboundary wall normal 0 0 1 dist [expr 1.5*$agrid]
> lbboundary wall normal 0 0 -1 dist [expr -$l+1.5*$agrid]
> 
> [...]
> "
> 
> So I changed it, didn't I. Still puzzled, why it doesn't work.
> 
> Markus Wink
> 
> 
> 
> -----Ursprüngliche Nachricht-----
> Von: address@hidden [mailto:address@hidden Im Auftrag von Ulf Schiller
> Gesendet: Donnerstag, 30. Januar 2014 15:12
> An: address@hidden
> Betreff: Re: [ESPResSo-users] Simulation of fluid using LB-method
> 
> On 01/30/2014 03:03 PM, Wink, Markus wrote:
>> Hello everybody,
>> 
>> I tried to think about of the real position of the wall:
>> "The (0, 0, 0) node of the LB lattice in Espresso is placed at (agrid/2, 
>> agrid/2, agrid/2)."
>> In my case, I chose a_grid =1, so I put the walls at 1.5 and 51.5 in the 
>> simulation box. Thus the length of the simulation box is 53 in my case, 
>> gibing a channel width of 50.
> 
> In that case the actual locations are 2.0 and 51.0, if I'm not mistaken 
> (Georg?). Then the width is 49.0 which would bring your v_max*50/49 
> close to the theoretical value.
> 
> Best,
> Ulf
> 
> -- 
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>