output total energy

Submitted by June on Thu, 12/31/2020 - 03:38

Dear LIGGGHTS users,

I want to monitor the change of total energy during dynamic relaxation. But I don't find the command to compute the total energy, and there is no thermodynamic output of the total energy. So how can I output the total energy of the system？

Thank you in advance.

Best wishes
June

Forums:

deepakpawar.2310 | Thu, 12/31/2020 - 10:46

I guess there no straightforward command for calculation of total energy of the granular system

However, the Work-energy balance in DEM SImulation can be summarized by following

Kinetic Energy +Internal Energy =External work done

>> here KE is the Kinetic energy
>> IE is the internal energy which is the sum of friction energy and strain energy
>> External work is the sum of work done by an external force, body force and rigid wall

I think KE's familiarity is well known,
But I think the internal energy calculation is going to be a complicated one because it also requires the calculation of strain energy with a friction force.
If you were able to handle the internal energy measurement, then it would certainly be feasible.

Thanks
Happy learning!

June | Thu, 01/07/2021 - 14:34

Thank you for your comments!
Is there a command in LIGGGHTS to calculate friction energy and strain energy directly? Or could you please provide a method
for calculating these two energies?

Best wishes,
June

deepakpawar.2310 | Fri, 01/08/2021 - 05:53

i have not come any across any such commands yet (probably in premium version of LIGGGHTS, it would be there).
Hence you have to do all the friction energy and strain energy calculations manually (quite possible for smaller system).

Thanks

happy learning !