After enabling beta features as described in Introduction, you can access expert options for the quadrature method of moments (QMOM). These options appear in the text user interface (TUI) under the following text menu:
define/models/multiphase/population-balance/expert/qmom
The available options are:
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inversion-algorithm Enables the use of the advanced moment inversion algorithm [1] for the solution of population balance equations. You can select from the following options:
0: the product-difference algorithm. See section “The Quadrature Method of Moments (QMOM)” in the Ansys Fluent Theory Guide for details.1: the Wheeler algorithm [2].
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realizable-moments? Ensures the reailzability of the moments of the PBE.
The product-difference algorithm is used to compute the weights and abscissas from the moments of the particle size distribution (see section “Numerical Method” in the Ansys Fluent Theory Guide for details). Typically, positive values of the weights and abscissa ensure that the distribution function also remains positive. The positive moments are called "realizable". To avoid non-physical values of the corresponding weights and abscissa, the moments should always remain realizable.
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print-realizable-moment-warning? When enabled, prints diagnostics for the realizable moments during the QMOM solution. This command is valid only when the
realizable-moments?option is enabled.