A spherical harmonics—Finite element discretization of the self-adjoint angular flux neutron transport equation
نویسندگان
چکیده
The spherical harmonics (PN) method is widely used in solving the neutron transport equation, but it has some disadvantages. One of them omes from the complexity of the PN equations. Another one comes from the difficulty of dealing with the vacuum boundary condition exactly. In his paper, the PN method is applied to the self-adjoint angular flux (SAAF) neutron transport equation and a set of PN moments equations coupled ith each other are obtained. An iterative method is utilized to decouple them and solve them moment by moment. The corresponding vacuum oundary condition is derived based on the Marshak boundary condition. The spatial variables are discretized on unstructured-meshes by use of he finite element method (FEM). The numerical results of several problems demonstrate that this method can provide high precision results and void the ray effect, which appears in the discrete ordinate (SN) method, with relatively high computational efficiency.
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