Opened 5 years ago

Last modified 5 years ago

#52 assigned Enhancement

Particle release density

Reported by: pesei Owned by: ignacio
Priority: major Milestone:
Component: FP physics/numerics Version:
Keywords: Cc:

Description

Presently, particles are released homogeneously in 4D space. They represent mass in the forward mode. Under well-mixed conditions, the mixing ratio should be constant. Thus, they should be released proportional to air density.

For not too large release domains, the difference will not be important.

It would also be better to release particles in a way that ensures homogenous filling of the release domain instead of randomly, as done now. For small particle numbers per time step, the randomness may lead to clustering of particles in parts of the domain.

Change History (2)

comment:1 Changed 5 years ago by ignacio

  • Owner changed from somebody to ignacio
  • Status changed from new to assigned

comment:2 in reply to: ↑ description Changed 5 years ago by pesei

Replying to pesei:

Presently, particles are released homogeneously in 4D space. They represent mass in the forward mode. Under well-mixed conditions, the mixing ratio should be constant. Thus, they should be released proportional to air density.

I have thought a bit more about that. It depends on how we treat the well-mixed condition and whether particles represent masses or mixing ratios. There are two concepts

  1. particles carry masses and the particle number density profile under well-mixed conditions should be proportional to the density profile
  1. particles carry mixing ratios and the particle number density profile under well-mixed conditions should be homogeneous

We have to make sure that these concepts are not arbitrarily mixed. I think the initial concept was 1., and then the way particles are released is ok (apart from the randomness which is not good), but what about bwd and domain-filling? 2. would be more natural here but it must be implemented throughout. We need to check carefully.

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