Changes between Version 15 and Version 16 of u/erica/OutflowFeedback


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Timestamp:
10/17/17 18:32:41 (7 years ago)
Author:
Erica Kaminski
Comment:

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  • u/erica/OutflowFeedback

    v15 v16  
    2222Now, jets are launched from rotating protostellar systems, so it makes sense to assign a 'spin' to the sink particle, induced from accreting angular momentum from the surrounding gas. While we do not explicitly conserve angular momentum in the code, angular momentum would be reduced in the grid due to the accretion step, and so to be conservative between the gas and sink particle, we assign a total accreted angular momentum to the sink as follows:
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    24 Note, this accreted ngular momentum is the sink's ''spin'' angular momentum, rather than its orbital angular momentum. This is because in addition to enforcing mass, momentum, and energy conservation between the gas and the sink particle, we also conserve the COM of the system.
     24Note, this accreted angular momentum is the sink's ''spin'' angular momentum, rather than its orbital angular momentum. This is because in addition to enforcing mass, momentum, and energy conservation between the gas and the sink particle, we also conserve the COM of the system.
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     26Question -- Why do we conserve the center of mass (COM) of the system -- is it the location of the sink particle (if so, doesn't that coincide with the gravitational potential minimum?).
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     28Question -- What is the spin angular momentum of the sink and how do we calculate it?
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     30So to recap, mass, energy, linear and angular momentum, and the COM is **conserved** between the gas and the sink particle in AstroBEAR's accretion module.
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     32Now we must transition to thinking about injecting some fraction of these conservatively accreted quantities back into the grid. How is this modeled in Astrobear (i.e. what quantities do we use at the sub-grid scale/SGS) and how are these quantities distributed in a conservative fashion throughout the kernel?
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     34== Feedback Kernel Equations ==
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