Multispecies and star formation?

[Nathan Goldbaum]

Hi all,

My understanding from going over the initializers that handle multispecies simulations is that the in-memory multispecies datasets stored in the BaryonField array are actually densities.

Taking a look at the star formation routines, it looks like only the Density field is modified when new star particles are created. However, to me, that seems inconsistent. Wouldn't one also need to scale the various species Density fields to the cell's new total Density after creating a new star particle? That of course assumes that all of the species contribute equally to the creation of a new star particle.

Does the rescaling actually happen somewhere else? Am I mistaken about the nature of the multispecies density fields?

Thanks for your help with this.

-Nathan

[Geoffrey So]

I'm not sure about the new Enzo, but in the old ~1.5 Enzo, in Grid_StarParticleHandler.C, during the SF and FB routine all fields were divided by baryon Density, at the end converted back

      for (k = GridStartIndex[2]; k <= GridEndIndex[2]; k++) {

for (j = GridStartIndex[1]; j <= GridEndIndex[1]; j++) {

 index = (k*GridDimension[1] + j)*GridDimension[0] +

   GridStartIndex[0];

 for (i = GridStartIndex[0]; i <= GridEndIndex[0]; i++, index++) {

   BaryonField[field][index] *= BaryonField[DensNum][index];

So that should take care of all baryon fields.

At least that's my understanding, correct me if I'm wrong.

From

G.S.

-Nathan

--
You received this message because you are subscribed to the Google Groups "enzo-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email to enzo-dev+u...@googlegroups.com.
To post to this group, send email to enzo...@googlegroups.com.
Visit this group at http://groups.google.com/group/enzo-dev?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.

[Nathan Goldbaum]

Thanks Geoffrey!  That clears it up.  It turns out the rescaling is in the latest versions of enzo as well.