A new fuel depletion code based on group-wised energy Bateman ODEs; SUDEPLET code for point-like PWR core

Abstract

A new efficient fuel depletion code for the PWRs (containing less than 5% average enrichment) is developed based on the Bateman five-energy groups coupled ODEs, and is called SUDEPLET (Shiraz University DEPLETion code). In the current article, SUDEPLET physical concepts and its approximation procedures are given, and also the SUDEPLET.exe file are attached and released as user friendly software without any limiting-access. The SUDEPLET execution schemes and inputs are explained, and the SUDEPLET is executed for three different suggested PWRs to find its verification. The SUDEPLET results (which include more than 200 tracked isotopes) are benchmarked with those results using other familiar fuel depletion analyzers such as ORIGEN 2.1 and/or MCNPX 2.6 (based on the BURNS card). Lack of a complicated input is the main improvement of the SUDEPLET code. Actually, thermal power, the BOC uranium isotopes masses, and cycle-time (in terms of days) are the main necessary input parameters for SUDEPLET executions. Another capability of the SUDEPLET is its ability to calculate the whole core average EXCESS reactivity due to uranium depletion of the core, temperature defects, and mixed burnable poisons in the fuel (or BARs). Among hundreds tracked isotopes; Cs-131, Cs-135, Cs-137, Sr-90, Tc-99, I-129 (which are problematic isotopes in the High Level Waste analysis); also Am-241 and Np-237 (which are most important problematic actinides in the HLW analysis) are highlighted and tabulated in the “Principle Window” of the SUDEPLET. Obviously, time-dependent uranium and plutonium isotopes masses are the main elements which are tracked during the cycles.