Subcritical, subsonic case

General Soln Behavior for this case (different ICs than this run, so just to qualitatively compare):

*Note vr is actually negative for infall

Initial conditions are here: InitialConditions.pdf​

128³, fixed grid

At this resolution (dx=.03125), the critical radius (rcrit=.0158) is contained within the kernel (r_acc=.125), but below the grid scale (r_min=.027). (Note r_min is the radius of the nearest cell to the sink particle). So, the soln doesn't turn over the way it does in the above plots, at this resolution. Instead, the density and radial velocity are monotonic.

A density comparison of the new algorithm (left) vs. the Krumholz algorithm (right):

Density lineouts comparison-

Mach comparison-

Sink mass vs. time-

However, since the density is going up near the sink particle, implies that the sink isn't accreting 'fast enough'. This is reflected as a decrease in the infall around the sink particle as pressure waves from the increased central density propagate outward:

Testing AMR compatibility

Image comparing 128³ fixed grid (left) vs. 64³ + 1 level (right) 20 frames into simulation:

There are slight differences between the runs (peak density/velocity, e.g.)…

Running at higher resolution

At 128³ + 1 level, dx_min=0.015625, which means the critical radius (r_crit=.0158) is slightly above the grid scale (r_min=.0135) and contained within the kernel (r_acc=.0625) . (Note r_min is the radius of the nearest cell to the sink particle).

Here's a lineout of the initial density, radial velocity, and mach number of this flow:

With movies:

Concerns:

-increasing/decreasing Lambda over time?

-mdot onto sink NEQ mass flux into kernel?

-subcycling over kernel before taking hydro step?

-AMR differences in solution?