Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Gerardo Aliberti Project Name: PROTEUS_APP Division: NE Project title: PROTEUS applications to the analysis of AmBB performances in the ASTRID reactor Associated funding: DOE-NE Nuclear Energy Advanced Modeling & Simulation (NEAMS) Other Systems: NE Division clusters Science: The Evaluation and Screening study performed by the Fuel Cycle Technology Office of the U.S. Department of Energy identified continuous recycling of uranium together with plutonium and/or transuranic elements in fast reactors, either alone or with supporting thermal reactors, as the most promising options for improving resource utilization and reducing high-level waste (HLW) generation. One potential path investigated in France considers Am-only recycle in Americium Bearing Blankets (AmBB) and direct disposal of Np and Cm. This allows recycling Am in a few specific radial blanket assemblies of a fast reactor, minimizing the repository impacts by transmuting Am, minimizing fuel handling impacts from Cm, and minimizing impacts on reactor performance and safety. In this context, reactor physics and fuel cycle analyses are conducted to assess different minor actinide (MA) transmutation strategies and to identify the irradiation experiments needed. Particularly, the AmBB transmutation performances are being evaluated in the 1500 MWth ASTRID and the 1000 MWth Advanced Burner Reactor (ABR). For this type of analysis, it is crucial to get detailed information on the neutronic performances of the Americium Bearing Blankets (AmBB). The current suite of deterministic neutronic codes traditionally used (namely REBUS-3) is poorly suited for performing such analysis, especially for pin-wise depletion calculations. On the other hand, Monte Carlo codes have the potential for providing invaluable information but at the price of large computational cost in order to reduce the statistical uncertainty in a fine-mesh pin-wise model that makes this type of simulations very unpractical o perform. Advanced code systems developed in the framework of the NEAMS project such as PROTEUS appear very promising since they allow detailed modeling while taking advantage of the features of a deterministic approach. Based on applications to simplified reactor models, it has been demonstrated that the PROTEUS code has the capabilities to perform neutronic calculations for detailed geometry models with explicit pin by pin representation, similarly to Monte Carlo codes. Particularly, PROTEUS is able to compute pin by pin neutronic features, such as pin-wise power/flux and neutron spectra. Thus, it is considered of great interest to benefit of the PROTEUS capabilities for the evaluation of the neutronic performances of the Americium Bearing Blankets (AmBB) in the ASTRID reactor. Unfortunately, pin by pin simulations for reactors of the ASTRID size with the PROTEUS code are computationally very demanding in terms of memory and require the use of a significant number of processors. It is a practically impossible to run such simulations on the machines currently available at the NE division. Thus, the accomplishment of the discussed analysis would be possible only through the use of high perfor mant machines, such as the blues supercomputer at Laboratory Computing Resource Center. Project description: A full core calculation of the ASTRID reactor with the use of the PROTEUS code and an explicit pin by pin modeling would be rather impossible to achieve even on the most performant supercomputers currently existing, due to the extremely demanding computational resources both in terms of memory and disk space that would be needed. However, the activity performed in FY2017 demonstrated that this type of study is feasible with the use of simplified models, where the pin by pin description is limited to a target assembly only while all other reactor assemblies are fully homogenized (in the homogenized assemblies, the heterogeneous effects are however taken into account by the cross section processing). To further reduce the burden of the required computational resources, calculations can be performed with the use of broader spatial meshes and lower transport approximations (angular flux expansion, anisotropic scattering order and energy group structure) prov ided that the subsequent impact on the results to be obtained is rather negligible. In fact, the simplifications discussed above were proven to have an impact only on the absolute calculated flux/power values while the effects on the normalized pin-wise flux/power distributions of the target AmBB assembly can be considered quite negligible. After validating the PROTEUS capabilities for the calculation of the pin-wise flux/power profile of the AmBB assemblies, new studies were started on the improvement of the transmutation performances of this type of assemblies in the 1500 MWth ASTRID reactor. In FY 2017, the option was investigated to add small contents of fissile material to the blanket. It was found that increasing the content of fissile added, the total flux in the target assembly increases, as expected, while the pin-wise profile becomes flatter. Based on the results of burnup calculations with the REBUS-3 code, it was found that the minor actinides transmutation in the AmBB assemblies show negligible benefits from the flux increase due to the addition of fissile material. In fact, by adding fissile to the blankets the total flux increase but the neutron spectrum is shifted to higher energies, with a subsequent negative impact particularly on the absorption cross section that plays a significant role in th e transmutation process. To increase the flux at low energies the option is being envisaged to replace some AmBB pins with moderator. However, this is expected to produce a peak power in the outer core, especially in the pins at the interface with the blanket, with consequent design issues. In this scenario the option can be eventually envisaged to load in the AmBB assemblies some absorber pins at the interface with the core. This type of analysis is planned for FY2018. Thus, it is crucial that the use of the LCRC supercomputers be allowed during the next fiscal year as well. In fact, even using simplified models the discussed PROTEUS applications are very demanding in terms of memory and require the use of a significant number of processors. It is a practically impossible to run such simulations on the machines currently available at the NE division. Industry partnership: Project URL: Current FY Hours Used: undetermined amount New FY Requested allocation: 1000000 Q1: 250000 Q2: 250000 Q3: 250000 Q4: 250000 Justification: Current applications of PROTEUS code are highly focused on solving challenge problems for customers and code validation. Past efforts were mostly focused on code development, as there was a major release, and so computational requirements were lower than presently needed. Storage requirements: Thank You, The LCRC Accounts System