1,720,974 research outputs found
ADS-Demo Fuel Rod Performance: Multivariate Statistical Analysis
No full textAmerican Nuclear Society, La Grange Park, IL, 200
LBE-XADS Fuel Rod Performance: Steady State and Transient Analysis
No full textAtomic Energy Press, 200
Thoria and Inert Matrix Fuels for a Sustainable Nuclear Power
No full textNuclear power to be sustainable requires the fulfilling of peculiar constraints, which include addressing the proliferation risk. One possible route for sustainability is that to adopt a fuel cycle based on thorium. However, comparison with uranium cycle indicates that thorium cycle utilization is premature. Instead, a promising short-term option is the use of inert matrix fuels, possibly containing thoria, in a once-through cycle. Irradiation tests performed in the Halden reactor show encouraging behaviour under irradiation. Furthermore, these fuels are very well suited for a direct disposal in a geological repository
Review stato programma Halden Project e definizione linee di R&S di interesse nazionale
No full textTechnical Report RdS/2011/22
Plutonia-Thoria Fuel Cycle as Starting Solution for a wider Thorium Use
Full text linkThis paper is focused on a description of thoria fuel option. Our opinion is that this option, beyond being a valuable way to exploit the energy content of plutonium without further breeding it, may be a starting point for introducing an Uranium-Thorium fuel cycle, based on a different strategic context with respect to past proposals. The option is based on the adoption of current or advanced PWRs, the latter characterised by a reduced fuel power density, always adopting conventional fuel rods and assemblies. A three-batches full core loading scheme is assumed. The thoria-plutonia composition is determined by the constraints to obtain at Beginning Of Life (BOL) a non positive void coefficient, and to reach a burnup as high as possible. Different fuel compositions and pellet radius are considered. The plutonium content is in the range of 4.5÷15%, mainly depending on the plutonium quality, namely Weapon Grade (WG) or Reactor Grade (RG). The results are in terms of dynamic coefficients, life duration, plutonium consumption and final isotopic compositions. These fuels show the capability to destroy about 40÷60% of total plutonium for RG, while this figure rises to 65÷70% for WG. These values are well above those obtained by MOX option. A variant to eliminate any proliferation concern foresees the addition of small quantities of 238U at the expenses of a reduction of the fuel burnup and its capacity in burning RG plutonium, while the opposite occurs for WG.
The low boron worth is not different from the MOX one, being related mainly to the plutonium content, and much less to the chosen fertile isotope. Therefore, modifications of control devices for a full core strategy is not expected to be different in the two cases.
The results confirm the viability of this proposal, apt to future variants, including those connected to accelerator actinide burning solution. An irradiation experiment, expe-cted to take place at Halden HWBR in the context of the ENEA participation to the Halden Project, is the main part of the Inert Matrix – Thoria fuel R&D activity presently underway as a Polytechnic of Milan–ENEA co-operation
Preliminary Analysis by means of the TRANSURANUS Code of Mixed Oxide Fuel Rod for Gen IV Lead Fast Reactor
No full textThree fast reactors (FR) are included in the Generation IV (GEN IV) nuclear system concepts: Sodium-cooled Fast Reactor (SFR), Gas-cooled Fast Reactor (GFR) and Lead-cooled Fast Reactor (LFR). FRs have a unique role in the actinides management due to
effective fissioning of the transuranic actinides (TRU) recovered from LWRs spent fuel. These GEN IV systems are capable, in principle, to operate with a complete recycle of all the uranium and TRU isotopes, providing a considerable increase in the available fuel resources and a decrease in the long term nuclear waste burden. These innovative systems can operate by using a wide range of fuel types including oxide, carbide, nitride, metal and dispersion fuels with different cladding material options. Concerning fuel technology, most of the gained experience refers to oxide fuels. Cross-cutting and generic open issues concerning fuel and cladding applicable to GEN IV nuclear systems will play an important role in the future nuclear fuel science. In this paper, a preliminary thermo-mechanical study, by means of the TRANSURANUS code (TU), is performed on mixed oxide fuel rods (MOX) operating in a LFR environment. To this purpose the design of the European Lead-cooled SYstem (ELSY), under study in the context of the EURATOM 6th FP, was used as reference. In ELSY, main GEN IV goals are pursued (sustainability, economics, safety and reliability, proliferation resistance and physical protection). The reference fuel rod is similar to that of a classical SFR with MOX, except for cladding material that in ELSY is assumed to be the ferritic-martensitic steel T91. At the next step, the minor actinides (MA) bearing (2-5 wt%) MOX will be considered, while a nitride fuel is the long term option. This preliminary ELSY fuel pin
analysis aims at investigating the expected deviations of its performances caused by moving from the reference MOX to a MA-containing mixed oxide fuel relevant for a closed fuel cycle option. Even if the empirical approach of this analysis relies on the carefully tested modelling of TRANSURANUS code, it must be noted that the calculations have been partly performed beyond the validated burnup domain of the code, therefore next due step will be the review of this “blind” introductory analysis to GEN IV LFR fuel rod on the basis of an experimental irradiation in the burnup domain of interest
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