[mrishi]

1. Can we understand the concept of parcel in kinematicCloud as a parcel representing a school of identical fish?What is the relation between "cloud" and parcel?

2. If I use a parcel with properties nParticle =1, does that effectively make it similar in behaviour to solidParticle?

If this holds it will be helpful to me in modelling a bubble swarm problem, where as we change volumetric flow rate, the nature of swarm goes from individual bubbles with a bubbling frequency, to a dense bubble cloud at higher flow rates. nParticle, size distribution and parcelsPerSecond seem to be three parameters apt to model this kind of evolution.

But it counts on the nParticle = 1 hypothesis. I have not been able to formulate a patchInjection for solidParticle so I haven't been able to compare the two scenarios, hence the question.


3. But when would one tune using nParticle vs using parcelsPerSecond? It seems a large number of parcelsPerSec would generate time-averaged statistics with stabler solution (The intermediate eulerian phase timesteps would not have alternating periods of very different agitation; for low parcelsPerSec (1-2), solution diverges, while for 10 it just stops, and for 100 and above it runs to give a reasonably physical result). On the other hand, what significance would it hold on the total number of PARTICLES which get introduced due to this?

[Artur.Ant]

The post is old but I'll try to give an answer, maybe it will help someone.


1. Can we understand the concept of parcel in kinematicCloud as a parcel representing a school of identical fish?What is the relation between "cloud" and parcel?

As I read a parcel is an ensemble of particles with the same characteristics (velocity, ...)
For some solvers, kinematicCloudProperties or kinematicCloudPositions are the files where you can store the information about the behaviour of your parcels.

2. If I use a parcel with properties nParticle =1, does that effectively make it similar in behaviour to solidParticle?

nParticle = 1 means that during the injection in any Parcel will be just one Particle.
To introduce the solid particle in your simulation you must choose the right options, such as density, Young modulus, reactions...

Remember that the parameters nParticle requires parcelBasisType=fixed.

3. But when would one tune using nParticle vs using parcelsPerSecond?

If you use nParticle in your dictionary you must define the parcelsPerSecond, in this way you define how much mass you want to introduce.
Let say that you put nParticle=1, your injection duration is 1e-2 [s] and you want to inject 5e3 particles -> in this case you must choose 5e+05 parcelsPerSecond