Re: [ESPResSo-users] How to enable lattice Boltzmann hydrodynamics?

[Ulf Schiller]

Chunda Zhou wrote:
> Hi guys,
> 
> I try add some water and added two lines " lbboundary wall dist 1.5
> normal 1. 0. 0.
> lbfluid agrid 1.0 dens 0.1 visc 1.0 tau 15.0 friction 0.01" in my
> script. But it said: "104 LB requires no Verlet Lists". What does this
> mean? I had disabled the thermostat. The full list of error is the
> following:
> 
> =======================================================
> =               ESPResSo Tutorial                     =
> =          Learning ESPResSo in 10 steps              =
> =======================================================
>  
> ESPResSo: 3.0.0
> { Compilation status { FFTW } { LJ_WARN_WHEN_CLOSE } { ELECTROSTATICS }
> { DIPOLES } { MASS } { CONSTRAINTS } { LENNARD_JONES } {
> LENNARD_JONES_GENERIC } { LJ_ANGLE } { SMOOTH_STEP } { SOFT_SPHERE } {
> LJCOS } { BOND_ANGLE_COSINE } { NEMD } { NPT } { DPD } { DPD_MASS_RED }
> { LB } }
> { Debug status { } }
> Simulate PE Solution N=82 at density 0.005
> Simulation box: 403.30593504362076
> background_errors 0 {104 LB requires no Verlet Lists}
>     while executing
> "lbfluid agrid 1.0 dens 0.1 visc 1.0 tau 15.0 friction 0.01"
>     (file "ac8.tcl" line 174)

The lattice Boltzmann implementation in ESPResSo requires Verlet lists
to be switched off because they would break the LB-MD coupling. Add

cellsystem domain_decomposition -no_verlet_list

to your script to avoid the error message.

Regards,
Ulf

-- 
Dr. Ulf D. Schiller                         Building 04.8,  Room 255
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