MATRIX-TYPE HIGHER-ORDER FUNDAMENTAL-SOLUTIONS TO 3-DIMENSIONAL 2-GROUP NEUTRON DIFFUSION-EQUATIONS

The zero-order and the higher-order fundamental solutions for the 3-D two-group neutron diffusion equations have been derived in such a way that these solutions satisfy the first and the second group equations simultaneously. Each degree of the solutions has a 2 x 2 matrix form b ased on two types of function, r(p) exp(-iBr) and r(p) exp(-kr). Singu larities of type (1/r) are only found at the diagonal components of th e zero-order solutions; however, no singularities are found at any com ponents of the higher-order solutions. These solutions can be used for applying the multiple reciprocity boundary element method to 3-D two- group neutron diffusion problems. (C) 1997 Elsevier Science Ltd.