| ... | ... | @@ -8,7 +8,7 @@ The HCS is the simplest non-trivial particulate gas-solid system. The continuum |
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gas-phase is initially at rest. The particles are uniformily distributed in space
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and have zero momentum in all three directions. However, the particle pecular
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velocity is non-zero, quantified by an initial *granular* temperature,
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:math:`T_0`. The system is periodic in all direcitons and no external forces act
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:math:`T_0`. The system is periodic in all directions and no external forces act
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on the system. Under homogeneous conditions, the granular temperature, :math:`T`,
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is equivalent to two-thirds of the the (massless) mean particle kinetic energy.
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In the HCS, the Eulerian kinetic theory (KT) model of Garzo et al. [GTSH12]_
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| ... | ... | @@ -62,7 +62,7 @@ the ideal :cpp:`BVK2` DNS drag law is applied, see [BvK07]_, [TPKKv15]_. |
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Three replicate systems are simulated with MFiX-Exa 19.08, differing only
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in initial particle locations and pecular velocities. The particle kinetic
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energy is averaged in the simulations (red) and compared to the analytical
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granular temperature (black) of the HCS as a funciton of time in the figure
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granular temperature (black) of the HCS as a function of time in the figure
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above. The kinetic energy :math:`KE / KE_0` decays by two to three orders of
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magnitude in line with the HCS result until clustering and localized mean
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motion cause a drastic deviation. The final result at :math:`t^* = 1000`
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| ... | ... | @@ -78,7 +78,3 @@ of the clustering instability the HCS. |
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Clustered state of the HCS observed by Goldhirsch and Zanetti [GZ93]_
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(left) compared to an MFiX-Exa result (right). |
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