20 | | As you can see in the left plot of rho, the density in the ambient, within a fictitious sphere of r=15, is increasing as the simulation progresses, going from darkest blue to lighter shades. This is coincident with increasing speeds in this region, likely due to the gravitational acceleration of a homologous collapse, of sphere r=15, rho=rho_ambient. The free fall time for the ambient is ~ . The boundary of the fictitious sphere is set up I believe from the Poisson boundary conditions or solver... I believe new material is not supplied at either this boundary or any physical boundaries after it is diminished, causing a rarefaction wave to be set up. Any winds coming in or going out from the physical boundary is just set to 0. Along the fictitious bounding sphere of R=15Rbe, material seems to be supplied from the external domain, and then this spherical region (1<r<15) seems to collapse homologously (shrinking and increasing density everywhere) for most of the sim. Speeds however, have a more complicated behavior. Outside of the sphere of r=15, speeds remain close to 0, but immediately within this sphere they continue to increase and move inward, becoming hypersonic near the spherical boundary early on. |
| 20 | As you can see in the left plot of rho, the density in the ambient, within a fictitious sphere of r=15, is increasing as the simulation progresses, going from darkest blue to lighter shades. This is coincident with increasing speeds in this region, likely due to the gravitational acceleration of a homologous collapse, of sphere r=15, rho=rho_ambient. The free fall time for the ambient is ~ 4Myr, or 0.25 in computational time (compare to the tsim = 0.216 above). The boundary of the fictitious sphere is set up I believe from the Poisson boundary conditions or solver... I believe new material is not supplied at either this boundary or any physical boundaries after it is diminished, causing a rarefaction wave to be set up. Any winds coming in or going out from the physical boundary is just set to 0. Along the fictitious bounding sphere of R=15Rbe, material seems to be supplied from the external domain, and then this spherical region (1<r<15) seems to collapse homologously (shrinking and increasing density everywhere) for most of the sim. Speeds however, have a more complicated behavior. Outside of the sphere of r=15, speeds remain close to 0, but immediately within this sphere they continue to increase and move inward, becoming hypersonic near the spherical boundary early on. |