Dear users,
I was using Hertzian model to calculate forces. I went initially with the default value for Kt used in lammps by specifying NULL which gives a value Kt/Kn=2/7 . I do understand that this is a very good value for Hookean model. However, for Hertzian this gives a value of Poisson’s ration greater than 0.5 (It gives nu=0.9) which is not good. May I know the reason why this ratio has been fixed like this in lammps for Hertzian model.
Yours faithfully,
Sonu Kumar
3rd Year B’Tech
IIT Guwahati
Inertia. Use the value appropriate for your material if you are concerned.
Respected Sir/Ma’am,
Can you please tell why a value of 2/7 for inertia and not any other value? Is there any research paper that cites those values? If possible, can you give me the link to the source.
The reason that ratio of 2/7 is most often used is because of inertia of prior work, so to speak (not the inertia of actual particles). That is to say - It’s used because that’s what folks early on in the area used.
As for references, I suggest doing what every researcher must do and do your own lit search. We’ve all got google these days and the papers aren’t hard to find. Check out the LAMMPS website for example - e.g. Silbert’s paper - if you want a starting place.
BUT to hammer my point of my first e-mail home in response to your first e-mail “May I know the reason why this ratio has been fixed like this in lammps for Hertzian model”
It’s not fixed - you are free to use whatever you like in place of NULL, appropriate for YOUR work.
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