EFFECT OF THE UNIFORM FISSION SOURCE METHOD ON LOCAL POWER VARIANCE IN FULL CORE SERPENT CALCULATION

One of challenges the Monte Carlo full core simulations is to obtain acceptable statistical variance local parameters throughout whole reactor at a reasonable computation cost. The tends be larger in low-power regions. To tackle this problem, Uniform-Fission-Site method was implemented code MC21 and its effectiveness demonstrated on NEA performance benchmark. very similar also Serpent under name Uniform Fission Source (UFS) method. In work effect UFS studied BEAVRS benchmark which based real PWR with relatively flat radial power distribution 3x3 mini-core simulated thermo-hydraulic thermo-mechanic feedbacks. It shown that application has no significant but equalizes axial power.