IAS-Astrophysics / athenak

Performance-portable version of the Athena++ astrophysical AMR-MHD code using Kokkos.
BSD 3-Clause "New" or "Revised" License
34 stars 24 forks source link

edit to Chakrabarti solution - [merged] #554

Closed jmstone closed 3 months ago

jmstone commented 8 months ago

In GitLab by @gonihalevi on Mar 1, 2024, 17:56

_Merges chakrabartisolution -> master

I have modified the GR torus problem generator to add the option of specifying 'n_param' in the input file for a Chakrabarti torus, for which the angular momentum profile is

l = c\lambda^n, where \lambda^2 = l/\Omega

Surfaces of constant \lambda are von Ziepel cylinders. If 'n' is unspecified in the input file, it is calculated (along with 'c') by assuming Keplerian angular momentum at the inner radius. If 'n' is instead specified, the angular momentum at the inner edge is no longer fixed at Keplerian. This allows one to construct equilibrium tori with different thicknesses for fixed inner and outer radius (lower 'n' makes thicker tori).

I have also modified the python script for calculating the location of pressure maxima to take 'n' as an optional input parameter, along with spin and inner and outer radii, so that one can calculate the desired 'r_peak' value.

Example: r_in = 10, r_out = 100, a = 0.9375

If 'n' is unspecified, you get a thinner torus with:

r_peak = 30.15

c = 1.25

n = 0.447

l_in = 3.62

l_peak = 5.78

If 'n = 0.25' is specified, you instead get a thicker torus with:

r_peak = 19.56

c = 2.25

n = 0.25

l_in = 4.08

l_peak = 4.77

Density slices for these two solutions are included below.

dens_nfree_10_100_slice_x1.png

dens_n025_10_100_slice_x1.png

jmstone commented 8 months ago

In GitLab by @gonihalevi on Mar 1, 2024, 18:00

added 1 commit

Compare with previous version

jmstone commented 8 months ago

In GitLab by @gonihalevi on Mar 1, 2024, 18:02

added 1 commit

Compare with previous version

jmstone commented 8 months ago

In GitLab by @jmstone216 on Mar 3, 2024, 09:50

mentioned in commit a4f14884e918a2d26e647ae8106b584f1bee900e