Positive PN Closures
نویسندگان
چکیده
We introduce a modification to the standard spherical harmonic closure used with linear kinetic equations of particle transport. While the standard closure is known to produce negative particle concentrations, the modification corrects this defect by requiring that the ansatz used to the close the equations is itself a non-negative function. We impose this requirement via explicit constraints in a quadratic optimization problem.
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عنوان ژورنال:
- SIAM J. Scientific Computing
دوره 32 شماره
صفحات -
تاریخ انتشار 2010