Effect of Spectral Shift on Conversion Ratio in (Th-233U)O2 Fuel

  • Mahmoud Dorrah Nuclear and Radiological Regulatory Authority, 3 Ahmed El-Zomor Street, El-Zohour District, Nasr City-Cairo 11762, Egypt
  • Abdallah Ibrahim Alexandria University, Hadara, Alexandria, 21544, Egypt
  • Mohsen AbouMandour Alexandria University, Hadara, Alexandria, 21544, Egypt
  • Hanaa Abou-Gabel Alexandria University, Hadara, Alexandria, 21544, Egypt
Keywords: Spectral shift, heavy/light water mixtures, conversion ratio, Th-233U oxides fuel.


Spectral shift principle was applied to modify resonance absorption in 232Th in a (232Th-233U)O2 fueled model of the Czech research LR-0 reactor. The aim was to obtain the best fuel utilization by varying the ratio of D2O/H2O in the moderator. MCNP code was used to model the LR-0 reactor. 11 different D2O / H2O mixtures viz.; 0%, 10%, …., 90%, 100% D2O were investigated. Conversion ratio of 232Th to 233U was maximal at 100% D2O.


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