[lammps-users] Temperature thermostat of Collision

Hi, Steve,
I am a graduate student in mechanical engineering. I want to simulate the collision of Nanoparticle and CNT using Lammps. But I am really confused with which Temperature thermostat I should use. In my simulation the nanoparticle is given an large initial velocity, but this will cause the temperature really large which is calculated by 3KT=mvv. So, when I use the NVT or NPT, the velocity of nanoparticle will decrease sharply which don’t make sense. And using the NVE will also make the Temperature uncontrollable. Could you please help me to figure out this problem. Thank you very much!

Best,

Rj Zhang

My opinion; I don't think you should use a thermostat at all.
Matt Petersen

Quoting Rongjun Zhang <[email protected]...>:

So, when I use
the NVT or NPT, the velocity of nanoparticle will decrease sharply which
don't make sense.

Thermostats change velocity. If the system is hot and the theromstat
says to cool it, it will reduce the velocities. If you don't want that to
happen, then as Matt said, don't use a thermostat.

Section 4.16 of the manual discusses various ways to compute temperature
and thermostat on various degrees of freedom.

Steve

Hi, all,

I think I get it, thank you very much.

Best,

Rj Zhang

2010/1/26 Steve Plimpton <[email protected]>