Momentum tracer methods

In Stokesian dynamics (Section VIII), a direct simulation is made starting with a randomly chosen initial particle configuration. The structure is allowed to evolve as part of the detailed fluid-mechanical solution, and the hydro-dynamic particle interactions are determined at least to the extent of assuming pairwise additivity of these interactions. The momentum tracer method (Section VIII) is characterized by the interesting feature that the particulate phase of the suspension is at rest. The static configuration of this suspension is... 

There are two exceptions to the use of the method described above, in which the flow field calculation can be disabled during the species calculation. First, if the sliding mesh model is used, the flow field data are required for each time step, so it is not possible to disable the flow field calculation to perform the species transport calculation. Second, if the tracer is to be added through an inlet or dip tube for a finite period of time, after which the inlet flow is disabled, calculation of the flow field should resume at that time, especially if the inlet delivers a jet of significant momentum to the vessel. 

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