Farklı sıcaklıklar altında BSR yakıt demetinin efektif çoğalma faktörü ve yakıt sıcaklığı katsayısı hesaplamaları

Bu çalışmada, Westinghouse tipi basınçlı su reaktörü (BSR) yakıt demeti için, çeşitli sıcaklıklarda farklı yanabilir zehirler ve ağırlık yüzdeleri kullanılarak efektif çoğalma faktörü (keff), doppler katsayı sonuçları ve yoğunluk hesaplamaları sunulmaktadır. Reaktör parametreleri olan keff ve doppler katsayıları, ZrB2 ile kaplanmış integral yakıtlı yanabilir zehir çubukları ve Gadolina-Uranyum (UO2-Gd2O3) integral yakıtlı yanabilir zehirler göz önüne alınarak hesaplanmıştır. Farklı sıcaklıklarda elde edilen sonuçlar, yanabilir zehiri kullanılmayan yakıt demeti sonuçları ile karşılaştırılmıştır. Artan sıcaklık değerlerinde, yakıt demetlerinde reaktiflik azalmış doppler katsayıları ise artmıştır fakat doppler katsayıları her sıcaklıkta negatif değerlerde kalmıştır. Sıcaklığın 1500 K’de olduğu durumda yanabilir zehirli olmayan temel yakıt demetinde efektif çoğalma faktörü 1.46985 iken ağırlık yüzdesi %2 ve %8 olan Gd2O3 ile IFBA yanabilir zehirli yakıt demetinin efektif çoğalma faktörü sırasıyla 1.38976, 1.37574 ve 1.30337olarak bulunmuştur.

Effective multiplication factor and fuel temperature coefficient calculations of PWR assembly under different temperatures

This paper presents effective multiplication factor (keff) with different burnable absorbers and weight percentages at different temperatures as well as doppler coefficient results and number density calculations for Westinghouse type pressurized water reactor (PWR) Assembly. Integral fuel burnable absorber rods coated with ZrB2 and Gadolinia-Uranium (UO2-Gd2O3) integral burnable absorbers were considered to calculate reactor parameters (keff and doppler coefficient). The results compared with base fuel which does not contain burnable absorber at different temperatures. The results show that reactivity was decreased with increased temperature and doppler coefficients increased with temperatures but remained negative at all temperatures. At 1500 K, the effective multiplication factor for base fuel was found to be 1.46985 while the effective multiplication factors for 2% with Gd2O3, 8% with Gd2O3, and IFBA rods were 1.38976, 1.37574, and 1.30337 respectively.

Keywords:

Burnable absorber, Doppler coefficient, reactor parameters fuel assembly,

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