Transport SP₃ based on pin by pin is an important anticipant in next generation reactor physics numerical methods. The nodal method for pin by pin calculation is not efficient because higher order flux and source expansion is assumed for large nodal size. Since reactor core heterogeneous happens usually in radial direction, a radial 2D plane flux fused with axial traditional nodal method is proposed for 3D pin by pin transport SP₃ calculation. A nodal iterations strategy based on nodal face current is adopted in all three directions. With IAEA 2D/3D and typical transport benchmark problem, the method is demonstrated correct and feasible for core transport and diffusion calculations.

A classical semi-analytical nodal method for neutron diffusion equation with second order neutron flux expansion in radial pin by pin level and 4th order expansion for axial neutron flux is used. A full core coarse mesh finite difference (CMFD) acceleration is adopted in order to achieve good calculation accuracy and efficiency. With IAEA 2D/3D benchmark problem and self-define 3D pin by pin reference problem numerical calculation, it is demonstrated that the proposed methodology achieve anticipated accuracy and with very good CMFD acceleration.