Re: [ESPResSo-users] lb thermostat

[Stefan Kesselheim]

Hi Dimiry,

On Oct 31, 2014, at 12:24 PM, Dmitry Zablotsky <address@hidden> wrote:

> Hello!
> 
> Is it right that the LB thermostat does not thermalize the rotational degrees 
> of freedom?

yes, that is right. 

> What is the best approach to this in espresso? 
> I could additionally activate the Langevin thermostat and remove its 
> influence on the translational coordinates, but this doesnt look like a good 
> option.

So far, we do not support only the point-like particle-fluid coupling suggested 
by Ahlrichs and Duenweg (ca 1999). It assumes a frictional force proportional 
to the relative velocity of the particle and the interpolated fluid velocity. 
Rotating particles should, of course, also couple their rotational degree of 
freedom, but this is so far not supported. Probably, it would be possible to do 
something similar, thus to assume a torque proportional to the difference of 
the angular velocity and the local vorticity of the fluid calculated by finite 
differences. 

Thus, probably Espresso does not yet support what you need. 
 
Hope that helps.
Cheers
Stefan