Criticality Analysis of Fuel Salt Composition and Enrichment Level in a 50 MWth Chloride-Based Molten Salt Fast Reactor

Abstract

Achieving high fuel utilization efficiency in Molten Salt Fast Reactors relies on the determination of an appropriate molten fuel salt composition. In this context, this study investigates the neutronic performance of a chloride-based NaCl–UCl₃ molten fuel salt for a 50 MWth cylindrical Molten Salt Fast Reactor (MSFR), which is a Generation IV nuclear energy system. Through analyses conducted using the MCNP6.3.1 Monte Carlo code and the ENDF/B-VIII.1 continuous-energy data library, the effects of varying heavy metal (UCl₃) molar ratios and initial ²³⁵U enrichment levels ranging from 19.75% to 35% on core criticality (keff) were examined. The findings indicate that UCl₃ molar ratios between 30% and 40% fail to satisfy the targeted criticality condition (keff > 1), whereas increasing the heavy metal fraction to 45% and above allows the reactor to reach the criticality limit.

Keywords

• Molten Salt Fast Reactor (MSFR)
• core criticality (keff)
• chloride-based molten salt

Ethical Statement

The authors of this article declare that the materials and methods they use in their work do not require ethical committee approval and/or legal-specific permission.

Thanks

This study was supported by the Scientific and Technological Research Council of Türkiye (TUBITAK) under the Grant Number 125M611. The authors thank TUBITAK for their support.

50 MWth Klorür Esaslı Ergimiş Tuz Hızlı Reaktöründe Yakıt Tuzu Bileşimi ve Zenginleştirme Oranının Kritiklik Analizi

Abstract

Ergimiş Tuz Hızlı Reaktörlerinde yüksek yakıt kullanım verimliliğinin sağlanması, uygun ergimiş yakıt tuzu bileşiminin belirlenmesine bağlıdır. Bu kapsamda, bu çalışmada 4. Nesil nükleer enerji sistemlerinden biri olan 50 MWth gücündeki silindirik bir Ergimiş Tuz Hızlı Reaktörü (ETHR) için klorür esaslı NaCl–UCl₃ ergimiş yakıt tuzunun nötronik performansı incelenmiştir. MCNP6.3.1 Monte Carlo kodu ve ENDF/B-VIII.1 sürekli enerji veri kütüphanesi kullanılarak gerçekleştirilen analizlerde, farklı ağır metal (UCl₃) molar oranları ile %19,75–35 arasında değişen başlangıç ²³⁵U zenginleştirme seviyelerinin kor kritikliği (keff) üzerindeki etkileri araştırılmıştır. Bulgular, %30–40 aralığındaki UCl₃ molar oranlarının hedeflenen kritiklik koşulunu (keff > 1) sağlayamadığını, buna karşılık ağır metal oranının %45 ve üzerine çıkarılmasıyla reaktörün kritiklik sınırına ulaştığını göstermiştir.

Keywords

• Ergimiş Tuz Hızlı Reaktörleri (ETHR)
• kor kritikliği (keff)
• klor bazlı ergimiş tuz

Ethical Statement

Bu makalenin yazarları çalışmalarında kullandıkları materyal ve yöntemlerin etik kurul izni ve/veya yasal-özel bir izin gerektirmediğini beyan ederler

Thanks

Bu çalışma, Türkiye Bilim ve Teknolojik Araştırma Konseyi (TÜBİTAK) tarafından 125M611 numaralı proje ile desteklenmiştir. Projeye verdiği destekten ötürü TÜBİTAK'a teşekkürlerimizi sunarız.

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