Analysis of the evolution of the actinides composition and their reaction rates in GFR600

Abstract

The present report explains the work done and the results achieved in the framework explained at the Introduction section. This work is the author’s Master Thesis that concludes the Industrial Engineering university career performed at ETSEIB (Escola Tècnica Superior d’Enginyeria Industrial de Barcelona), UPC (Universitat Politècnica de Catalunya). It also concludes the specialization on Nuclear Engineering performed at the ‘Department of Physics and Nuclear Engineering’ at the same institution. Thanks to the ENEN framework (European Nuclear Education Network) and the students exchange program within European universities (Erasmus), this Thesis could be developed at BME (Budapest University of Technology and Economics), Budapest, Hungary. The Thesis is useful as well as the required work in order to apply for the EMSNE (European Master of Science in Nuclear Engineering) next year. Based on SCALE (Standardized Computer Analyses for Licensing Evaluation) [4] simulations for the GFR600 (IV Generation Nuclear Reactor) and their output data files, the Thesis analyses how the reaction rates and the actual amounts of the different actinides (former elements of the fuel) evolve during the years of usage in the reactor. These simulations use to take very long time to be ready and this prevents to be able to calculate different input compositions results in a short time. The idea that pushes the Thesis is the thought that is possible to develop a linear model that could give similar results to those gotten with the original exponential model used in SCALE code with a much quicker calculation. The Thesis treats basically two fields: - the creation of an understandable linear model able to calculate the burn-up for the fuel within acceptable tolerance margins. - the actinides reaction rates evolution analysis in dependence with their relative mass in the core, in order to study the so called self-shielding, and predict their cross sections without using SCALE’s given ones. The results achieved in the Thesis will be a support data for the analysis of the fuel cycle of a symbiotic nuclear energy system consisting of GFR600 and LWR units. When performing this report there was the thought that it is a part of a greater project, and because of that it has been understood that the software created for this Thesis will be useful for anybody who might continue the study for such a problem (MAs transmutation capabilities of a symbiotic nuclear energy system consisting on GFR600 and LWRs). This is why there has been put a lot of effort on explaining subroutines created for example. The development of this work has required a quick learning of FORTRAN and MATLAB programming languages. FORTRAN has been selected because other pieces of work within this symbiotic nuclear energy system project will be developed with the same language; MATLAB has been selected in order to visualize graphically large amount of data. An ANNEX report has been added with the FORTRAN code created. Next chapter points out the specific objectives of this work, and will be a starting point on evaluating the conclusions at the end.