Cummulate heat and output

Dear All.

I have tried to get cummulate heat.

So I used NEMD

Heat Source

fix HOT hot nvt temp 400 400 1

Heat Sink

fix COLD cold nvt temp 200 200 1

and get the cummulate heat

fix ave/time command to set f_nvt_left f_nvt_right .

but the result shows that f_nvt_left are f_nvt_right all increasing positive value as time goes by.


TimeStep f_nvt_left f_nvt_right

502000 671.674 493.083
504000 3398.89 1994.32
506000 6497.95 3774.62
508000 9764.41 5656.12
510000 13164.8 7579.8
512000 16618.2 9528.75
514000 20068.8 11504.9
516000 23518.4 13485.2
518000 26998.6 15464.7
520000 30475.5 17452.7
522000 33936.6 19453.2

Should f_COLD the eliminating heat be, right(negative) ?

and I could not find the output information (f_npt or f_langevin) when these are used in ave

please, Could you let me know any the number of manual section?

Best regard

There is too much information missing.

Is your system properly equilibrated before starting data accumulation?

Is your system stable? and your force field and simulation settings sound?
After equilibrating the system to a single global temperature, you should be able to continue running for quite some time with fix nve and without a thermostat and the temperature and total energy should not drift or extremely little.

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Thanks for your reply.

Oh. I did nvt at room temp before set heat sink and source.

but. I did not nve. as your comment, I should have run nve for stabilization.

I will try it! thanks so much :slight_smile:

Best regards.

That says nothing about whether this was done for a sufficient amount of time and whether the system is stable. You need to visualize your system, monitor energies and when posting here, provide a complete input, logfile and - if needed - before/after visualization images.

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