كد مصرف سوخت راكتورهاي PWR با غناي متوسط كمتر از %5: كد SUDEPLET

Fuel depletion code for PWRs with less than 5% enrichment: SUDEPLET code

در اين پژوهش كد ساده و كارآمد محاسبات مصرف سوخت انواع PWR (با غناي متوسط قلب كمتر از %5) با نام SUDEPLET (Shiraz University DEPLETion code) توسعه يافت. در اينجا مفاهيم فيزيكي و روش¬هاي تقريبي مورد استفاده در آن آورده شده ¬است. توانمندي¬هاي برجسته اين كد شامل انجام محاسبات مصرف سوخت بدون نياز به هندسه پيچيده قلب راكتور، توانايي محاسبه كاهش راكتيويته قلب صرفاً بر اساس مصرف سوخت در طول زمان (كه در بدست آوردن غلظت اسيد بوريك يا مكان ميله¬هاي كنترل در قلب، سودمند است) و نمايش مقادير جرمي پاره¬هاي شكافت بر حسب عدد جرمي و عدد اتمي است. براي راستي آزمايي نيز نتايج SUDEPLET با نتايج كد مستقل ORIGEN2.1 مقايسه شده است.

An efficient fuel depletion code for the PWRs containing less than 5% average enrichment is developed, called SUDEPLET (Shiraz University DEPLETion code), and is released along with the present article. In the current article, SUDEPLET physical concepts and its approximation procedures are given herein. The SUDEPLET execution schemes are explained through the current article, and moreover, the SUDEPLET code is executed for three different typical PWRs (contains less than 5% enrichment), and obtained results are benchmarked with those results using another independent fuel depletion code analyzer such as ORIGEN2.1. The most important capability of the SUDEPLET is its ability to calculate fuel depletion without use the complex geometry of the core and calculate the core reactivity decrease due to only core fuel depletion at any desired burnup which may be used to estimate the control rods’ withdrawn position and/or boric-acid dilution at any cycle-time (to compensate for the whole core decrease of fission rate due to fuel depletion). The SUDEPLET also gives the produced fission fragments’ yields versus their atomic mass number. In addition, among these calculated fission fragments Cs-137, Sr-90, Tc-99, I-129 which are problematic isotopes in the High Level Waste analysis; also Am-241and Np-237 which are actinides (and another long-term heat-emitters in the depleted fuel) are highlighted within all obtained fission fragments and trans-uranic elements.