Browsing Faculty of Engineering by Author "10119582 - Serfontein, Dawid Eduard"
Now showing items 1-9 of 9
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Assessment and reduction of proliferation risk of reactor-gradeplutonium regarding construction of ‘fizzle bombs’ by terrorists
Serfontein, Dawid E.; Mulder, Eben J.; Reitsma, Frederik (Elsevier, 2014)The approximately 23.7 wt% 240Pu in reactor-grade plutonium denatures the 239Pu to the extent that it cannot fuel high yield nuclear weapons. 240Pu has a high spontaneous fission rate, which increases the spontaneous neutron ... -
Different techniques for reducing DLOFC fuel temperatures in a PBMR-DPP-400 core
Tchonang Pokaha, Marius; Serfontein, Dawid E. (Elsevier, 2018)This article addresses the topic of modifying the fuel cycles of Pebble Bed Reactors in order to reduce their maximum fuel temperatures during Depressurised Loss of Forced Coolant (DLOFC) accidents, in order to prevent ... -
A generic method for automatic translation between input models fordifferent versions of simulation codes
Serfontein, Dawid E.; Mulder, Eben J.; Reitsma, Frederik (Elsevier, 2014)A computer code was developed for the semi-automatic translation of input models for the VSOP-A diffusion neutronics simulation code to the format of the newer VSOP 99/05 code. In this paper, this algorithm is presented ... -
Neutron poison distribution in the central reflector to reduce the DLOFC temperature of a Th-LEU fueled OTTO PBMR DPP-400 core
Pokaha, Marius Tchonang; Serfontein, Dawid E. (Taylor & Francis, 2018)In a previous study using a mixture of thorium and 20 a/o% LEU at 16 gram per fuel sphere heavy metal loading and adjusting the effective fuel enrichment to produce the same amount of cumulative energy per fuel sphere as ... -
Optimisation of deep burn incineration of reactor waste plutonium ina PBMR DPP-400 core
Serfontein, Dawid E.; Mulder, Eben J.; Reitsma, Frederik (Elsevier, 2014)In this article an original set of coupled neutronics and thermo-hydraulic simulation results for the VSOP 99/05 diffusion code are presented for advanced fuel cycles for the incineration of weapons-grade plutonium, ... -
Reducing DLOFC fuel temperatures by mixing thorium with LEU in a single-zone six-pass fuel cycle in a PBMR-DPP-400 core
Tchonang, Marius; Serfontein, Dawid E. (ANS (American Nuclear Society), 2016)Many studies have been done in neutronics and thermal-hydraulic simulation of the standard 6-pass fuel recirculation scheme for the standard 9.6 wt % enriched, 9 g per fuel sphere low-enriched uranium (LEU) fuel in the ... -
Sharp reduction in maximum fuel temperatures during loss of coolantaccidents in a PBMR DPP-400 core, by means of optimised placementof neutron poisons
Serfontein, Dawid E. (Elsevier, 2014)In a preceding study, coupled neutronics and thermo-hydraulic simulations were performed with the VSOP-A diffusion code for the standard 9.6 wt% enriched 9 g uranium fuel spheres in the 400 MWth Pebble Bed Modular Reactor ... -
Thorium-based fuel cycles: reassessment of fuel economics andproliferation risk
Serfontein, Dawid E.; Mulder, Eben J. (Elsevier, 2014)At current consumption and current prices, the proven reserves for natural uranium will last only about 100 years. However, the more abundant thorium, burned in breeder reactors, such as large High Temperature Gas-Cooled ... -
Using thorium to reduce the maximum fuel temperatures during depressurized loss of coolant accidents in a once-through-then-out (OTTO) PBMR DPP-400 core
Tchonang Pokaha, Marius; Serfontein, Dawid E. (Taylor & Francis, 2017)This article presents the results for the PBMR-DPP-400, but for a once-through-then-out (OTTO) refueling scheme. An optimization attempt of the axial and radial power profiles is reported. The main aim was to reduce the ...