Bertalot, Luciano

Fischer, Ulrich

Juarez, Rafael

Serikov, Arkady

KITopen

KIT – The Research University in the Helmholtz AssociationNeutronic effects of Diagnostic Shield Module length on radiation environment of ITER Diagnostic Generic Upper Port PlugDevelopment of the new 3D MCNP neutronics model of the ITER Diagnostic Generic Upper Port Plug (DGUPP) – it is a baseline UP model for insertion into the ITER tokamak standard models (C-lite & C-Model). The model incorporates DGUPP design changes caused by implementation of the ITER Project Change Requests (PCRs) 439 & 709 concerning the design updates of UPP/blanket interface and UP remote handling.Neutronics analysis of DGUPP integrated in UP of the MCNP C-lite Ver. 2 Release R150304 ITER model consisted of 400 toroidal sector. Calculation of radiation 3D maps: neutron flux and Shut-Down Dose Rate (SDDR) in corridors of UPP Inter-Space Structure (ISS), where personnel access is planned 106 seconds (~12 days) of cooling time. Minimization of the SDDR in the DGUPP ISS – parametric analysis of the length of the Diagnostic Shielding Module (DSM) by filling with the DSM shielding material all the UP structure till the UP Closure Plate.Karlsruhe Institute of Technology (KIT)Institute for Neutron Physics and Reactor Technology (INR)Fusion Neutronics GroupHermann-von-Helmholtz-Platz 1D-76344 Eggenstein-Leopoldshafenhttp://www.inr.kit.edu* Corresponding author:arkady.serikov@kit.eduArkady Serikova*, Luciano Bertalotb, Ulrich Fischera, Rafael Juarezca Karlsruhe Institute of Technology (KIT), Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germanyb ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex, Francec UNED, Calle Juan del Rosal 12, Madrid 28040, SpainMain objectives of the workThis work has been funded by the ITER Organization under the ITERcontract Nr. IO/4300000896.The views and opinions expressed herein do not necessarily reflect those ofthe ITER Organization.Poster P0323Conclusions and future workAcknowledgment & DisclaimerDesign development of the ITER Diagnostic Generic Upper Port Plug (DGUPP) is still in progress. 3D maps of neutron fluxes and Shut-Down Dose Rate (SDDR) with iso-surfaces plotted the DGUPP allowed to find the radiation pathways, hot spots - most critical areas from neutronics perspectives.Revealed radiation streaming along the bottom and side gaps and inside the empty space of port structure behind the short Diagnostic Shielding Module (DSM) motivated the need to improve further the design of DSM. In all cases, the shielding design improvement should follow the ALARA principle, using the low activated materials with reduced contents of impurities - parent isotopes contributed to short and long term SDDR (Co, Ta, Ni, Nb).A variant of Long DSM has been analyzed. The engineering implementation of the Long DSM option is still under consideration. Along that, particular attention should be devoted to shielding insertion at the trapezoidal-to-rectangular reshaping of the UP rear structure. At this place neutron streaming could be stopped most effectively. Presented neutronics results were obtained in parametric study of the DGUPP shielding performance. These results are not absolute, they depend on other systems of ITER model C-lite V2 of 2015, which was updated afterwards to .A study has been carried out Neutronic investigation is planning for further DGUPP improvement and SDDR reduction by taking into account the updated ITER C-Model and by aiming to find the realistic engineering design solutions.Fusion neutronics computational methodologyMCNP local model of DGUPP with three constituent parts of the Diagnostic Shielding Module (DSM) used in following two models (a) and (b):(a) Short-DSM DGUPP with only one DSM part (1);(b) Long-DSM DGUPP with three DSM parts (1)+(2)+(3).DGUPP with three variants v1-v3:short DSM v1=14.4 ton, den. 3.3 g/cm3long DSM (v2=20 ton den. 3.3 g/cm3or v3=25 ton with den. 6.2 g/cm3)Neutronics effects on DGUPP radiation environmentTotal neutron flux map of the DGUPPv1 with short DSM in ITER C-lite MCNP modelDGUPP v2 component Volume,  mm^3 Volume, cc Density, g/cc Mass, g Mass, tonDGUPP structure 1.23642E+09 1.23642E+06 7.93000E+00 9.80485E+06 9.80485E+00DFW 3.44980E+08 3.44980E+05 6.34400E+00 2.18855E+06 2.18855E+00DSM original (IO IDM = SZVXHJ_v1_1) 7.41477E+08 7.41477E+05 3.27830E+00 2.43078E+06 2.43078E+00Total 14.4DSM rear‐ext. R3 8.93435E+05 3.27830E+00 2.92895E+06 2.9DSM rear‐ext. R4 1.40669E+06 3.27830E+00 4.61154E+06 4.6….DSM rear‐ext. R5 1.71106E+06 3.27830E+00 5.60935E+066.19501E+00 1.06000E+07 to be 10.6 tonSumdensity in DSM extension should be 25 tonExtension parts (2)+(3) of Long DSMMCNP model of DGUPP in C-lite ver.2-Inter-Space Structure SDDR effect of n‐streaming in gaps around the DGUPP is 77 microSv/h for both the models with or without the neutron cross‐talks from EP & LP.Neutron cross‐talk from Equatorial & Lower Ports (EP & LP): effect of activation by neutrons from EP & LP is 75 microSv/h. ‐ The total weight of the Reference DGUPP (IO IDM ref. SZVXHJ_v1_1) is 14.4 ton – weight settings to the DGUPP components are in Table‐ Volume and material density of the DSM in DGUPP is increased to correspond the 25 ton weight specification.‐ In DGUPP the DSM is described as homogenised dummy – DSM material fractions were adjusted (steel, B4C, water, void) to the new drain density of 6.195 g/cc.Table of weightsState-of-the-art codes approved for ITER applications:SpaceClaim software for CAD processing;SuperMC (FDS, China) for CAD-to-MCNP conversion;Activation and SDDR calculations FISPACT-2007 (CCFE) inventory code; R2SMesh interface code for MCNP-FISPACT;Radiation transport calculations (n/gamma fluxes) MCNP5 v1.60, MCNP6 (LANL) code; FENDL-2.1 (IAEA) neutron cross-section library.MCNP C-lite V2 R150304 ITER model with DGEP design of 2015 and Cryopump LP400 tor. sector of ITER

Neutronic effects of diagnostic shield module length on radiation environment of ITER diagnostic generic upper port plug

https://publikationen.bibliothek.kit.edu/1000075910/4495273

Neutronic effects of diagnostic shield module length on radiation environment of ITER diagnostic generic upper port plug

Abstract

Similar works

Full text

Available Versions

KITopen