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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
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R. C. Lloyd, E. D. Clayton
Nuclear Science and Engineering | Volume 60 | Number 2 | June 1976 | Pages 143-146
Technical Paper | doi.org/10.13182/NSE76-A26870
Articles are hosted by Taylor and Francis Online.
A series of experiments was performed providing new criticality data on plutonium-uranium nitrate solutions in cylindrical and spherical geometry. For the experiments in cylindrical geometry, the plutonium content of the total uranium plus plutonium was ∼30 wt%; whereas, in the case of the water-reflected spheres, measurements were performed with both 15 and 30 wt% plutonium. The uranium in the mixture was slightly depleted, containing 0.66 wt% 235U. The plutonium concentration covered by these experiments ranged between 12.4 to 97.3 g Pu/ℓ (uranium plus plutonium concentrations between 30 to 310 g/ℓ. The 240Pu content of the plutonium was 5.6 wt% in the first case and 4. 7 wt% in the second. The experiments were analyzed using ENDF/B-III cross-section data, and criticality factors were computed in each case. Some comparative calculations also were made, showing the differences obtained with ENDF/B-II, ENDF/B-III, and GAMTEC cross sections. The KENO code, with ENDF/B-III cross sections, as well as the HFN code, provide conservative results on the criticality factors for these systems. The average value of the computed keff for the cylinders, using KENO, was 1.022, and for the spheres, 1.024 using HFN. Thus, using these methods and cross-section data, the computed critical masses and volumes would be expected to be smaller than those measured by ∼2% in terms of keff.