Query about the thermostat

Hello,I have two questions about the the thermostat .
In a heat transfer simulation, the thermostat is used to adjust temperature to a constant value, why do not set the temperature difference for heat transfer simulation in the next line, but rather it usually runs a few steps.Then it will set the temperature difference.Why ?Is it goal to make the system temperature balance ? If it is, which output can be used to judge if the system equilibrium ?

Thanks!

Best regards!

I don't understand your questions.

If you want to monitor equlibration, then plot the
temperature(s) of the 2 reservoirs, and/or the
temperature profile between them.

Steve

2011/9/14 王丹 <[email protected]>:

Hello,I have two questions about the the thermostat .
In a heat transfer simulation, the thermostat is used to adjust
temperature to a constant value, why do not set the temperature difference

no. this is a common misinterpretation of what a thermostat
algorithm does. it (usually gently) tries to adjust properties
(velocities or accelerations) in a way so that that the _average_
temperature remains close to the desired value. this is why
you have a time constant representing the "reaction time".
this time is supposed to be "large", so that the thermostat
algorithm does not modify the dynamics too much and the
simulation properly represents the desired ensemble.

cheers,
     axel.

for heat transfer simulation in the next line, but rather it usually runs a
few steps.Then it will set the temperature difference.Why ?Is it goal to
make the system temperature balance ? If it is, which output can be used to
judge if the system equilibrium ?

i am not an expert in this, but i wold suspect to avoid resonances
in the coupling algorithm.