Question of lattice boltzmann temperature

Hi there,

I am currently using lattice boltzmann method coupled with molecular dynamics to simulate a vesicle in lattice boltzmann fluid. The hydrophilic part(head beads of lipids) are integrated using lattice boltzmann by fix lb/fluid command while the hydrophobic part (tail beads) is integrated using ‘fix nvt’ command. Both fix command set equilibrium temperature of 310K, But the final equilibrium temperature is well below that , only 166K. The iteration is 500000 steps. So 166K is equilibrium temperature. I am also using fix lb/rigid/pc/sphere command so that the hydrodynamic force can be transferred from fluid to vesicle. I’m really confused why the equilibrium temperature is much lower than the set value.

Thank you,

For the LAMMPS part (fix nvt), you have to be

sure you are thermostatting the correct degrees

of freedom and particles and that what you are printing

out (with thermo ouput) is the same as what

the thermostatting fix (fix nvt) is using.

For the LB part, if you have questions, please contact

the author listed for the USER contributed package.


Hi Steve,

I’m sorry I don’t get your explanation for the molecular dynamics part.
And how to use lammps website to contact authors of user contributed package? (what do you mean by authors of user contributed package)?

Thank you

Lattice Boltzmann in LAMMPS is in a user-contributed

package. All the files are in src/USER-LB. As is

a README file that tells you how to contact them.

doc/Section_packages.html and doc/Section_start.html

explain the difference between standard and user packages.