insert particles from files when resume the simulation

[wanqing0421]

If I want to insert particles through particlePhasicFlow but not delete the particles that already exist in the previous simulation, is there any way to do that?

[PhasicFlow]

setFields
{
   
    defaultValue 
    {
        velocity        realx3  (0 0 0);         // linear velocity (m/s)

        acceleration    realx3  (0 0 0);         // linear acceleration (m/s2)

        rVelocity       realx3  (0 0 0);         // rotational velocity (rad/s)

        shapeName       word    sphere1;         // name of the particle shape 
    }

    selectors
    {

    }
}

positionParticles                                // positions particles 
{
    method         ordered;                      // other options: random and empty

    mortonSorting  Yes;                          // perform initial sorting based on morton code?   

    orderedInfo
    {
        distance  0.004;                         // minimum distance between particles centers

        numPoints 30000;                         // number of particles in the simulation 

        axisOrder (z y x);                       // axis order for filling the space with particles
    }

    regionType      box;                         // other options: cylinder and sphere  

    boxInfo                                      // box information for positioning particles 
    {
        min (-0.08 -0.08 0.015);                 // lower corner point of the box 

        max ( 0.08  0.08 0.098);                 // upper corner point of the box 
    }
}

This is a sample dictionary. I think we must define a new keyword here to mange operations between starting from scratch and appending new particles to already existing particles.

action    new; // append and new are options 

The other matter is the fact that what would the behavior of setFields be? It applies the field values to the new particles or all particles (new + old)?

What if the new particles are being read from the file, do we have to delete particles which are in contact with previous ones?

The distance is defined in positioning particles, should we assume that it remains unchanged from previous to new one? of we just assume that the distance is valid for new particles and we check contact only for new particles?

we should consider all the states and find the best solution.

[wanqing0421]

Thanks for your solution,

1. setFields should be applied in the append particles.
2. We don't need to consider the collision between new particles and old particles, user should be responsible for the particle position to ensure that there are no overlap between new particles and old particles.

I think the dictionary should be add a new keywords based on the time, so that we can append new particles based on the existing time folders.

[PhasicFlow]

1. The particles are added to the time folder that is specified by startTime in settingsDict, so we dont need to specify further keyword here.
2. We can put the option for collision check with previous particles too. What do you think? checkCollision or checkCollisionWithExisiting

One more thing, do we check for collision when we are reading positions from file? If not, do we really need to do that?