Add a new property of particles

Hi All,

Anyone could please instruct me how to add a new property of particles, such as moisture around the particles. I think it could be similar as define a property like temperature of particle, which is already in the LIGGGHTS. But I have no idea about the procedure of working on a new property. Any help or hint would be highly appreciated! If possible, a detailed example is best for me to learn it.

Thanks so much!

Kun
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Hi All,

As previous post, following fix_heat_gran.h/.cpp and fix_heat_gran_conduction.h/.cpp, property of particle moisture could be defined in coding similar as temperature (temp). Then I would like to continue coding as when two particle contact, moisture will transfer between these two particle, and fix_scalar_transportation_equation is also modified as:

if(capacity_flag)
{
for (int i = 0; i < nlocal; i++)
{
if (mask[i] & groupbit){
capacity = fix_capacity->compute_vector(type[i]-1);

if(fabs(capacity) > SMALL) {quantity[i] += (flux[i] + source[i]) * dt / (rmass[i]*capacity);} else {quantity[i] += (flux[i] + source[i]);}

}
}
}
So I set capacity=0 to use:
quantity[i] += (flux[i] + source[i]);

And flux=0.01 as trial case defined in fix_MC_gran_liquid_bridge in my own file.

However, when two particles with diameter of 0.02 and timestep of 0.0005 are used, the flux for the first contact is 0.1, which is 10 times as defined. And when particle diameter is defined as 0.03, the flux for the contact is 0.13, which is 10 times as defined. It seems the flux depend on diameter and timesteps which is not desirable.

Could anyone please let me know where to find out this bugs?

Thanks!

Kun