Changes between Version 12 and Version 13 of u/EricasLibrary


Ignore:
Timestamp:
09/06/11 16:21:53 (13 years ago)
Author:
Erica Kaminski
Comment:

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  • u/EricasLibrary

    v12 v13  
    3030=== Tests ===
    3131Tests included collapse of Bonner Ebert and singular isothermal spheres.
     32
     33[[CollapsibleEnd]]
     34
     35[[CollapsibleStart(Foster and Chevalier (‘93))]]
     36
     37=== Summary ===
     38
     39Authors ran simulations with an outer density of 1/1000 the density at the outermost edge of the clump, whereas my simulations used 1/100. The ambient therefore had a large sound speed throughout the constant pressure medium (pressure = pressure in sphere at edge), and since the ambient region was very large, the pressure remained nearly constant throughout. They found that if the sphere was initialized with the Larson-Penston solution, it followed the analytical LP soln'. If grid was initialized to by the singular isothermal sphere, it followed Shu's solution.
     40
     41=== Stability Tests ===
     42
     43The 'marginally stable sphere' had a xi=xiCrit=6.451. A density enhancement of 1% above equilibrium value was needed to bring out expected stability behavior:
     44
     45* xi = 3, flow oscillated about v=0 for ~ 15 free fall times
     46* xi = 6.451, collapse happened in 5 ff times
     47* xi = 20, collapse happened in 6 ff times
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     49
    3250
    3351[[CollapsibleEnd]]