Investigation of isotopically tailored boron in advanced fission and fusion reactor systems /
This research examines the use of B^11, in the form of metallic boron and boron carbide, as a moderating and reflecting material. An examination of the neutronic characteristics of the B^11 isotope of boron has revealed that B^11 has neutron scattering and absorption cross sections favorably compara...
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1989.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Summary: | This research examines the use of B^11, in the form of metallic boron and boron carbide, as a moderating and reflecting material. An examination of the neutronic characteristics of the B^11 isotope of boron has revealed that B^11 has neutron scattering and absorption cross sections favorably comparable to those of Be^9 and C^12. Preliminary analysis of the neutronics of B^11 were performed by conducting one dimensional transport calculations on an infinite slab of varying thickness. Results showed that B^11 is superior to graphite as a reflecting and shielding material for both fission and fusion reactor systems. Beryllium is the best of the three materials in reflecting neutrons due primarily to the contribution from (n,2n) reactions. As a shielding material the (n,2n) reaction becomes a liability for beryllium, particularly if 14 MeV neutrons are present. Tailored neutron energy beam transmission experiments were carried out to experimentally verify the predicted neutronic characteristics of B^11. To further examine the neutron moderating and reflecting characteristics of B^11, the energy dependent neutron flux was measured as a function of position in an exponential pile constructed of B4C isotopically enriched to 98.5 percent B^11. After the experimental verification of the neutronic behavior of B^11, further design studies were conducted using metallic boron and boron carbide enriched in the B^11 isotope. The use of materials isotopically enriched in B^11 as a liner in the first wall/blanket of a magnetic confinement fusion reactor demonstrated acceptable tritium regeneration in the lithium blanket. Analysis of the effect of contaminant levels of B^10 showed that B^10 contents of less than 1 percent in metallic boron produced negligible adverse effects on the tritium breeding. A comparison of the effectiveness of graphite and B[^11]4C when used as moderators in a reactor fueled with natural uranium has shown that the maximum k[infinity] for a given fuel rod design is approximately the same for both materials. Approximately half the volume of the moderator is required when B[^11]4C is substituted for graphite to obtain essentially the same k[infinity]... |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Nuclear Engineering." |
| Physical Description: | xii, 125 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |