DEVELOPMENT OF NEW QUADRATURE SETS WITH THE "ORDINATE SPLITTING" TECHNIQUE

The Discrete Ordinate Method (SN) is one of the most widely used techniques to solve the linear Boltzmann equation. A commonly used technique for the generation of discrete ordinates and associated weights (quadrature set) is the level-symmetric. However, this technique is limited to order S20. To deal with highly angular dependent situations, we have developed different quadrature techniques including PN-EW, PN-TN and a new angular refinement approach referred to as “ordinate splitting”. We have tested these new quadrature sets using the Kobayashi 3-D problem 3, and demonstrated that PN-TN with ordinate splitting is an effective approach for highly directional problems.