Leichtle, Dieter

Richiusa, Maria Lorena

Čufar, Aljaž

English

KITopen

Introduction• Limiters play a crucial role in the operation of DEMO• Upper limiter integration was done in several steps(Talk: M. L. Richiusa et al – P6A4, Thursday afternoon)• Simplistic models used in initial analyses• Radial dependence of the nuclear loads (“1D”) – to investigate the general behavior and determine suitable cooling channel density• Effect of different shielding mixtures on the deposited nuclear loads • Effect of different shielding mixtures on the neutron/gamma shielding performance• Detailed models based on initial results used in more detailed analyses• More detailed modelling, but still simplistic, i.e. cooling channels not explicitly modelled• Detailed 3D maps of the nuclear loads – to study local behavior• Design of the cooling solution was optimized based on these results(Poster: A. Froio et al – PS3-3, Thursday)• This work is part of ISFNT paper: M. L. Richiusa et al, The Integrated Engineering Design Concept of the Upper Limiter within the EU-DEMO LIMITER SystemConclusions• Simple model for initial investigations, detailed model to determine local behavior• No problems found with shielding performance• Detailed 3D maps of nuclear heating, DPA, and He production• Integral and peak values of nuclear loads informed future design directions1. Tolls used• SuperMC [1] for CAD to MCNP  geometry conversion• MCNP5 v1.60 [2] and JEFF 3.3 [3] nuclear data for analyses4. Detailed model of upper limiter• More realistic geometry• 3 plasma facing layers + attachment layer• Shielding block still homogenized – basedon plate design5. Analyses using a detailed model• Nuclear loads of interest• Nuclear heating in limiter (total per component and mesh based)• DPA, He production in limiter• Peak nuclear heating in TFC: 6 W/m3 (limit 50 W/m3) – good shielding properties• DPA in vacuum vessel (VV): 0.2 DPA / 6 FPY (limit 2.75 DPA) – VV is far from the limiterAljaž Čufar1, Maria Lorena Richiusa2,3, Dieter Leichtle41 Reactor Physics Department, Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia 3 UKAEA-CCFE, Culham Science Centre, Abingdon, Oxon, OX14 3DB, UK2 Department of Engineering Science, Oxford Thermofluids Institute, University of Oxford, Oxford, OX2 0ES, UK 4 Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Karlsruhe, GermanyNeutronic analyses for EU DEMO upper limiterBox design Plate design Alt. plate designPFC-1 Tungsten (100 vol%)PFC-2 – tube layerTungsten (39.5 vol%), CuCrZr (17.0 vol%),oxygen free Cu (13.5 vol%), water (30 vol%)PFC-3 – bottom layerEurofer (39.5 vol%), tungsten (21.0 vol%),void (39.5 vol%)Shielding block Eurofer (53 vol%), water (47 vol%, at 0.92 g/cm3)Eurofer(87.5 vol%), water (7.4 vol% at 0.92 g/cm3), void (5.1 vol%)Eurofer(87.5 vol%), water (7.4 vol% at 0.7 g/cm3), void (5.1 vol%)3. Analyses using simple limiter model• Total nuclear heating of each layer• Radial dependence of nuclear heating• For different SB configurations and TBB concepts • Minor differences in deposited energy for HCPB• Significantly different heating radial profile in WCLL2. Simple limiter model• Initial simulations carried out using simple model• 3 plasma facing layers• Shielding block (homogenized water-Eurofer mix)• Shield block (SB) configurations – homogenized• Box design – Eurofer box with water filling• Plate design – Eurofer plates cooled by water channels• Analysis of radial dependence of nuclear heating• HCPB and WCLL tritium breeding blanket (TBB)6. Further work• Upper limiter as a reference for other limiters• Initial work already done on• Outboard midplane limiter (OML)• Outboard lower limiter (OLL)References[1] Y. Wu, FDS Team, CAD-based interface programs for fusion neutron transport simulation, Fusion Engineering and Design 84 (2009), 1987-1992.[2] F. Brown et al, Verification of MCNP5-1.60, LA-UR-10-05611, Los Alamos National Laboratory (2010).[3] JEFF 3.3: https://www.oecd-nea.org/dbdata/jeff/jeff33/Layer Material compositionPFC-1 (20 mm) Tungsten (100%)PFC-2 – layer with cooling pipes (17 mm)Cu (11.70 vol%), CuCrZr (14.81 vol%), water (26.33 vol%, at 0.935 g/cm3), tungsten (47.17 vol%)PFC-3 (3 mm) Tungsten (100%)PFC attachmentlayer (23 mm)Eurofer (21 vol%), void (79 vol%)Shielding block Eurofer (92.85 vol%), water (5.28 vol% at 0.7 g/cm3), alumina (1.87 vol%)0,00E+005,00E+001,00E+011,50E+012,00E+012,50E+013,00E+010 5 10 15 20 25 30 35 40Nuclear heating density [w/cm3 ]Radial distance from front surface [cm]Box design - HCPB Alter plate design -HCPBBox design - WCLL Alter plate design - WCLLNuclear heating [MW]Box design Plate design Alternative plate designHCPB WCLL HCPB WCLL HCPB WCLLPFC-1 1.99 2.57 2.00 2.56 2.00 2.60PFC-2 1.04 1.34 1.02 1.32 1.02 1.32PFC-3 1.06 1.38 0.88 1.11 0.87 1.09SB 4.55 9.35 4.47 5.77 4.35 5.54Sum 8.64 14.6 8.37 10.8 8.24 10.5Fig 4: Nuclear heating [W/cm3]Layer Nuclear heatingPFC-1 2.35 MWPFC-2 1.46 MWPFC-3 0.376 MWPFC attachment layer 0.171 MWShielding block 5.18 MWPFC cooling pipes (outside of PFC)29.2 kWPFC cooling liquid (outside of PFC)34.4 kWSum 9.60 MWFig 5: Neutron induced damage in tungsten [DPA/FPY] Fig 6: Neutron induced damage in Eurofer [DPA/FPY]Fig 3: Detailed model of the upper limiterTab 4: Total nuclear heating per componentFig 1: Simple model of the upper limiterTab 1: Material composition of analyzed cases for the simple limiter designFig 2: Radial dependence of the nuclear heating for different analyzed casesusing simple upper limiter modelTab 2: Total nuclear heating per layerTab 3: Material composition of layers for the detailed limiter design.Fig 7: Simple neutronics model used for initialOML and OLL analyses.

Neutronic analyses for EU DEMO upper limiter

https://publikationen.bibliothek.kit.edu/1000163094/151500618

Neutronic analyses for EU DEMO upper limiter

Abstract

Similar works

Full text

Available Versions

KITopen