Dear lammps users,

In lj units, dimensionless time is t* = t (epsilon / m / sigma^2)^1/2.

But in granular materials, there is no epsilon kind of thing. So, what

is the dimensionless time in granular materials.

Thanking you

Shantanu

Dear lammps users,

In lj units, dimensionless time is t* = t (epsilon / m / sigma^2)^1/2.

But in granular materials, there is no epsilon kind of thing. So, what

is the dimensionless time in granular materials.

Thanking you

Shantanu

I think it's the same - you can just assume eps = 1.

See the granular papers by Grest on the LAMMPS pub

page - they discuss LJ units for granular materials.

Steve

Hi Shantanu,

As far I understand the \sqrt{d/g} and 1/shear rate, can form the dimensionless time in granular matter. The first one (\sqrt{d/g}) is for simulations having gravity and later one (1/shear rate) is for shearing simulation without gravity. At least Campbellās work on granular material show that. So one can form the non dimensional time as t*=t/ \sqrt{d/g} or t*=\gamma*t, where d is particle diameter, g is acceleration due to gravity and \gamma is the applied shear rate.

Regards,

Vidya