Anguiano, M.

Arbeiter, F.

Becerril, S.

Carvajal, M. A.

Hernández, R.

Moreno, J. A.

Mota, F.

Oliver, C.

Palma, A. J.

Qiu, Y.

Ternero, M.

Vila, R.

Álvarez, I.

English

KITopen

Neutron fluence rate [10¹⁴ n/cm²s] Model CLC.v1.0 CLC.v2.0Beam RIG 43 26 43 2620x5 cm²LayoutMin 1.58 -44.8% 0.76 -29.5% 1.77 -42.7% 0.78 -30.9%Max 4.54 58.7% 1.60 48.1% 4.84 56.6% 1.50 38.9%Average 3.12 9.1% 1.16 7.4% 3.23 4.5% 1.15 1.8%SPND 2.86 1.08 3.09 1.1310x5 cm²LayoutMin 1.03 -36.4% 0.62 -23.9% 1.16 -31.4% 0.63 -27.2%Max 2.83 74.7% 1.16 42.2% 2.95 74.6% 1.23 41.2%Average 1.72 6.2% 0.88 8.6% 1.81 7.1% 0.89 2.3%SPND 1.62 0.81 1.69 0.87Quantification of the uncertainties in the determination of the final dose of the High Flux Test Module (HFTM) samples in IFMIF-DONESI. Álvarez ¹, M. Anguiano ¹, F. Mota ², F. Arbeiter ³, S. Becerril ⁴, M. A. Carvajal ¹, R. Hernández ²,  J. A. Moreno ¹, C. Oliver ², A. J. Palma ¹, Y. Qiu ³, M. Ternero ¹, R. Vila ²¹ University of Granada, UGR, Granada, Spain² Centro de investigaciones energéticas, medioambientales y tecnológicas, CIEMAT, Madrid, Spain³ Karlsruhe Institute of Technology, KIT, Karlsruhe, Germany⁴ IFMIF-DONES España, Granada, Spainiac@ugr.es• IFMIF-DONES is a neutron irradiation facility which aims at providing the irradiationmaterials data required for the construction of future fusion reactors.• The HFTM is designed to expose material specimens to high neutron flux conditions,generated by a deuteron beam directed at a lithium target.• The neutron damage will depend on different factors such as the irradiated material, thedose received, the neutron spectra, the dose rate and the temperature. So, thedetermination of the neutron fluence to which the specimens in the HFTM of DONESare exposed is a fundamental parameter for further specimen analysis.• Using Self Powered Neutron Detectors (SPNDs) in each rig inside the HFTM is possibleto obtain the neutron flux and estimate the dose absorbed by the specimens. The fluxwill be different in the 32 SPND.• Two different specimen distribution have been designed: CLC.V1.0 and CLC.V2.0. Theacronym comes from capsule loading configuration. The principal characteristics arepresented in the table.This project has been financed by the European Union’s FEDER program, IFMIF-DONES Junta de Andalucia’s program at the Universidad de Granada.This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No101052200 — EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neitherthe European Union nor the European Commission can be held responsible for them.Characteristics of specimen distributionCLC.v1.0 CLC.v2.0Eurofer volume [%] 48.16 84.77Liquid metal (Na) [%] 21.86 12.92Specimens per rig 101 120• Online detector which measures neutron and photon flux• Gives an electrical signal in proportion to the incident fluxes of neutronand/or photon• Multi-layered design: emitter, insulator and collector• Main nuclear processes to create current: (n, β-), (n, γ, e-), (γ, e-)IFMIF-DONES SpecimensSelf-powered neutron detectors (SPNDs)Use the detailed SSTT payload in HFTMEstimate the dose in samples in HFTM with MCNPEstimate the dose in samples depending on the detectors availableHomogeneous rigs modelQuantify the uncertainties in the measurement of the doseThe first estimation of the current in the SPND has been obtained taking onlyinto account the process (n, β-), that means the 95% of the signal for a RhSPND.Variation of neutron fluence rate [n/cm²s] in specimens and SPNDsFor the calculation, the material are ¹⁰³Rh,alumina and Inconel600. The spectrum dataare for the SPND in CLC.v1.0 model. Asobserved in the table, the electrical currentvalues are higher when the SPND is fartherfrom the neutron source.Specimen areaHigh Flux Test Module (HFTM)Specimens distributionHorizontal cut-plane of specimen capsulesSpainRig numeration11264345For both sample models, neutron fluence rate have been obtained using twodifferent IFMIF-EVEDA beam sizes, 20x5 cm² and 10x5 cm². Two rigs with a highgradient have been selected to compare the different cases: 43 and 26. For eachrig, the maximum, minimum and average neutron fluence rate values received bythe specimens inside the rig, as well as the value reaching the SPND, have beenobtained. As can be seen, the values vary significantly from one rig to anotherand also with changing beam size. Relative differences have been calculated withrespect to the SPND value, and substantial fluctuations in flux values areobserved within the same rig, where a single SPND per capsule is employed as areference point.Conclusions and next stepsElectrical current estimation (μA)RIG 45 26 1120x5 cm² 1.79 2.97 9.9510x5 cm² 1.61 3.66 11.8Neutron fluence rate [n/cm²s] 1∙10¹³ 2∙10¹³ 5∙10¹³ 1∙10¹⁴ 2∙10¹⁴ 5∙10¹⁴CLC.v1.0 CLC.v2.0► The estimated electric current in the SPND is lower when the SPND is closer tothe neutron source. This is because there are more fast neutrons than thermalneutrons, and β- generation is more likely in this case.► This information needs experimental validation in order to enhance the accuracyof the simulation model and the response of different emitter SPND materials willbe studied for the IFMIF-DONES neutron spectrum.► The spread of the fluences within a specimen set is relatively high and thedifference vs. the single SPND value of the same capsule can be up to +75%.Additional assumptions or measurements (i.e. activation) are necessary for ameaningful dose assessment of individual specimens. However, the SPNDvalue reflects the average dose in the rig quite well.The graphic shows the neutron spectrums in different SPND with different beamsizes (left axis) and the neutronic capture for the ¹⁰³Rh cross-section (right axis).SPND SPNDBeamSPND details

Quantification of the uncertainties in the determination of the final dose of the High Flux Test Module (HFTM) samples in IFMIF DONES

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Quantification of the uncertainties in the determination of the final dose of the High Flux Test Module (HFTM) samples in IFMIF DONES

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