Abstract
A computational module was developed in this work for the calculation of thermochemical equilib-ria bearing in mind the application of the module to chemical phenomena in nuclear fuel. Gibbs energy minimization principles set forth by Gunnar Eriksson in the SOLGASMIX program were applied for the calculation of thermochemical equilibria along with some improvements published in the literature. The underlying theory behind Gibbs energy minimization is presented, and the pro-gram applying this theory developed in this work is described in detail.
To increase understanding of the chemical phenomena to be modelled with the program, chemis-try of nuclear fuel in operation was reviewed. In the review, the chemistry of the actinides uranium and plutonium along with the fission products formed in irradiated nuclear fuel were explored.
Published thermochemical treatments of irradiated nuclear fuel and the applications of thermo-chemical modelling to nuclear fuel were reviewed to gain knowledge of state of research in this matter. Thermodynamic data for this system in the form of the Royal Military College of Canada Fuel Thermochemical Treatment was found to be publicly available, and this data was applied in this work.
The program developed in this work was tested and in many cases was found to calculate results comparable to other, established programs. Even difficult cases possible in the application of irra-diated nuclear fuel were evaluated with the new program. Finally, a simulation of oxygen potential in a nuclear fuel rod under irradiation was performed with the new program with fission product amounts generated by the point depletion code ORIGEN and temperatures and pressures in the fuel rod calculated with the fuel performance code FRAPCON.
To increase understanding of the chemical phenomena to be modelled with the program, chemis-try of nuclear fuel in operation was reviewed. In the review, the chemistry of the actinides uranium and plutonium along with the fission products formed in irradiated nuclear fuel were explored.
Published thermochemical treatments of irradiated nuclear fuel and the applications of thermo-chemical modelling to nuclear fuel were reviewed to gain knowledge of state of research in this matter. Thermodynamic data for this system in the form of the Royal Military College of Canada Fuel Thermochemical Treatment was found to be publicly available, and this data was applied in this work.
The program developed in this work was tested and in many cases was found to calculate results comparable to other, established programs. Even difficult cases possible in the application of irra-diated nuclear fuel were evaluated with the new program. Finally, a simulation of oxygen potential in a nuclear fuel rod under irradiation was performed with the new program with fission product amounts generated by the point depletion code ORIGEN and temperatures and pressures in the fuel rod calculated with the fuel performance code FRAPCON.
| Original language | English |
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| Qualification | Master Degree |
| Awarding Institution |
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| Supervisors/Advisors |
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| Award date | 17 Sept 2014 |
| Place of Publication | Espoo |
| Publisher | |
| Publication status | Published - 2014 |
| MoE publication type | G2 Master's thesis, polytechnic Master's thesis |