Comparison of simplified and standard spherical harmonics in the variational nodal method

Journal Article · Sun Dec 31 04:00:00 EST 1995 · Transactions of the American Nuclear Society

OSTI ID:411645

Lewis, E E ^[1]; Palmiotti, G ^[2]

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1. Northwestern Univ., Evanston, IL (United States)
2. Argonne National Laboratory-West, Idaho Falls, ID (United States)

Recently, the variational nodal method has been extended through the use of the Rumyantsev interface conditions to solve the spherical harmonics (P{sub N}) equations of arbitrary odd order. Here, we generalize earlier x-y geometry work to fit the corresponding simplified spherical harmonics (SP{sub N}) equations into the variational nodal framework. Both Pv and SP{sub N} approximations are implemented in the multigroup VARIANT code at Argonne National Laboratory in two- and three-dimensional Cartesian and hexagonal geometries. The availability of angular approximations through P{sub 5} and SP{sub 5}, and of flat, linear, and quadratic spatial interface approximations allows investigation of both spatial truncation and angular approximation errors. Moreover, the SP{sub 3} approximation offers a cost-effective method for reducing transport errors.

• OSTI ID: 411645
• Report Number(s): CONF-951006--
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Vol. 73; ISSN 0003-018X; ISSN TANSAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CALCULATION METHODS
DISCRETE ORDINATE METHOD
RADIATION TRANSPORT
SPHERICAL HARMONICS
TRANSPORT THEORY