Changes between Version 30 and Version 31 of u/BonnorEbertMatched
- Timestamp:
- 06/18/12 12:41:03 (12 years ago)
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u/BonnorEbertMatched
v30 v31 7 7 8 8 9 :[[Image(lightparams.png, 3 7%)]], :[[Image(domainParamsMatched.png, 39%)]]9 :[[Image(lightparams.png, 30%)]], :[[Image(domainParamsMatched.png, 31%)]] 10 10 11 11 '''Computational Scales:''' 12 12 13 :[[Image(sCALESmatched.png, 3 5%)]]13 :[[Image(sCALESmatched.png, 30%)]] 14 14 15 15 '''Results:''' 16 16 17 Note the line marking 'dx' denotes the size of the smallest cells in the grid, those within the BE sphere's center most regions (dx~0.06). The cells outside a radius of 150% Rbe (radius of BE sphere), however, made up the coarsest level grid (see below movies of the mesh) and had dx~1.62 pc for smaller grid and dx~3 pc for larger grid. The last time frame of data included in these plots and the movies below is the time before the collapse was no longer resolved adequately with the refinement criteria used. Since the aim of this study was to look at the initialization of the collapse, the refinement used here was sufficient. The time in which the sphere's P (Rbe) > Pcrit was t~0.15 myr, ~ 4% of a crossing time (and how much of the free fall time?).17 Note the line marking 'dx' denotes the size of the smallest cells in the grid, those within the BE sphere's center most regions (dx~0.06). The cells outside a radius of 150% Rbe (radius of BE sphere), however, made up the coarsest level grid (see below movies of the mesh) and had dx~1.62 pc for smaller grid and dx~3 pc for larger grid. The last time frame of data included in these plots and the movies below is the time before the collapse was no longer resolved adequately with the refinement criteria used. Since the aim of this study was to look at the initialization of the collapse, the refinement used here was sufficient. The time in which the sphere's Pram(Rbe) > Pcrit was 2.3<tc<3 myr, ~ 67%<tff<88% (see below calculation in approximations section). 18 18 19 :[[Image(vrad.png, 45%)]] [[Image(VradM.png, 45%)]] 19 '''''Radial Velocity-''''' 20 21 :[[Image(vrad.png, 40%)]] [[Image(VradM.png, 40%)]] 22 23 '''''Density-''''' 24 20 25 :[[Image(rho.png, 47%)]] [[Image(rhoM.png, 43%)]] 21 26 22 27 It is interesting to compare these plots to those of a similar collapse study in which the critical BE sphere in a light medium (same density and homogeneity as in the light ambient of this study) was triggered to collapse with a density enhancement above equilibrium values [https://clover.pas.rochester.edu/trac/astrobear/wiki/u/BonnorEbert#Collapse (click here)]. 23 28 29 '''''Thermal Pressure-''''' 24 30 25 31 The horizontal line in the following plots is the value of Pcrit, where Pcrit~1.14 Cs^8^/G^3^*M^2^ and characterizes the maximum external pressure a critical BE sphere can withstand before collapsing. Note that both the thermal and ram pressure at the Bonnor Ebert surface, Rbe, is BELOW the threshold under light ambient medium conditions, whereas in the "matched" ambient medium case both of these pressures EXCEED the threshold. 26 32 27 33 :[[Image(ThermalP.png, 47%)]] [[Image(thermalPM.png, 43%)]] 34 35 '''''Ram Pressure-''''' 36 28 37 :[[Image(RamP.png, 45%)]] [[Image(ramPM.2.png, 47%)]] 29 38