Mass transfer modeling for LM blanketsIn this presentation:Mass transfer in the LM flows is one of the key phenomena affecting blanket performance and safetyMain objectives of mass transfer modelingWhat do we need?What tools do we use?CATRIS: MATHEMATICAL MODELSMODELING EXAMPLESRiga experiment 1/11: setupRiga experiment 2/11: resultsRiga experiment 3/11: resultsRiga experiment 4/11: mathematical modelRiga experiment 5/11: material properties*Riga experiment 6/11: modeling resultsRiga experiment 7/11: modeling resultsRiga experiment 8/11: modeling resultsRiga experiment 9/11: modeling resultsRiga experiment 10/11: modeling resultsRiga experiment 11/11: conclusionsTritium transport, 1/6Tritium transport, 2/6Tritium transport, 3/6Tritium transport, 4/6Tritium transport, 5/6Tritium transport, 6/6Slide 26Mass transfer modeling for LM blankets Presented by Sergey Smolentsev (UCLA)with contribution from:B. Pint (ORNL)R. Munipalli, M. Pattison, P. Huang (HyPerComp)M. Abdou, S. Saedi, H. Zhang A. Ying, N. Morley, K. Messadek (UCLA)S. Malang (Consultant, Germany)R. Moreau (SIMAP, France) A. Shishko (Institute of Physics, Latvia)Fusion Nuclear Science and Technology Annual MeetingAugust 2-4, 2010UCLAIn this presentation:•Status of R&D on development of MHD/Heat & Mass Transfer models and computational tools for liquid metal blanket applications•Examples: corrosion & T transportOTHER RELATED PRESENTATIONS at THIS MEETINGTITLE Presenter Oral/PosterTritium Transport Simulations in LM BlanketsH. ZhangUCLAoralModeling Liquid Metal Corrosion S. SaediUCLAposterIntegrated Modeling of Mass Transport Phenomena in Fusion Relevant FlowsR. MunipalliHyPerCompposterMass transfer in the LM flows is one of the key phenomena affecting blanket performance and safety Traditionally, major considerations associated with the LM flows are the MHD effects. But there are more…. Tritium permeation is an issue – no solution has ever been proven Corrosion/deposition severely limits the interfacial temperature and thus represents an obstacle to developing attractive blankets at high temperature operationBlanket: “Hot” leg. Mass transfer coupled with MHD. Corrosion. T production. T leakage into cooling He. Formation of He bubbles in PbLi and trapping T. Ancillary system: “Cold” leg. Turbulent flows. Wall deposition and bulk precipitation. T leakage into environment. T extraction. Cleaning up.Main objectives of mass transfer modeling Blanket:•Revisit maximum PbLi/Fe t (470 ?) and wall thinning (20 m/year ?)•Estimate T leakage into cooling He streams in the blanket Ancillary system:•Estimate T leakage into environment•Model T extraction processes•Model clogging/deposition•Model clean up processes Phenomena, design:•Address “new” phenomena (i.e. He bubble formation in PbLi and trapping T by the bubbles)•Find new design solutions/modificationsChallenge! The whole PbLi loop, including the blanket itself and the ancillary equipment, must be modeled as one integrated systemWhat do we need?•New phenomenological models for: - interfacial phenomena - nucleation/crystallization - particle-particle/wall interaction - MHD effects on mass transfer - T transport physics •New material databases (He-T-PbLi) •New mass transfer solvers and their coupling with existing MHD/Heat Transfer codes He bubble transport and trapping Tby the bubbles is not well understoodWhat tools do we use?•HIMAG as a basic MHD/Heat Transfer solver•Many UCLA research MHD, Heat & Mass transfer codes•CATRIS (in progress) as a basic mass transfer solver•Many thermohydraulic / mass transport codesThe R&D on the development of newphenomenological models and theirintegration into numerical codes is underwayCATRIS: MATHEMATICAL MODELS1. Dilution approximation, Ci<Ci02. Lagrangian particle tracking, Ci>Ci03. Multi-fluid model, Ci>>Ci01Kpp kkdVdtr==�VF( ) ( )ii i i iCC D C qt�+ � =� � +�V1Nii i ijjJtrr=�+�� =��V1Nk k k ki ii i i i i ijjVtrr r=�+� =� + +��VVσ g PMODELING EXAMPLESExample Description Modeling status#1Riga experimentModeling of “corrosion” experiment in Riga, Latvia on corrosion of EUROFER samples in the flowing PbLi at 550 in a strong magnetic fieldGood match with experimental data on mass loss. Addressing groove patterns needs more sophisticated modeling. #2 Tritium transportNumerical analysis of tritium transport in the poloidal flows of the DCLL blanket with SiC FCI under DEMO blanket conditionsAnalysis for the front duct of the DCLL DEMO OB blanket has been done using a fully developed flow model.#3Magnetic trapModeling of extraction of ferrous material suspended in the flowing liquid in a magnetic trapFirst “demo” results have been obtained using Lagrangian particle tracking model under some assumptions for B~ 0.1 T.#4Sannier equationModeling of corrosion of ferritic/martensitic steels in turbulent PbLi flows to reproduce existing experimental data and to address the effect of a magnetic fieldIn progress. Computations are performed using the UCLA corrosion code (Smolentsev). Turbulence in a magnetic field is modeled via “k-eps” model.Riga experiment 1/11: setupSimulation of “CORROSION” EXPERIMENT in RigaPbLi loopEUROFER samplesB=0, B=1.7 TT=550CU=2.5 cm/s, U=5 cm/sTime=2000 hoursRectangular duct, 2.7x1 cm2Two 12-cm sections of 10 samples in a row, one section at B=0 and one at B=1.7 T Courtesy of Dr. Andrej Shishko, Institute of Physics, LatviaRiga experiment 2/11: resultsMacrostructure of the washed samples on the Hartmann wall in 3000 hrs at 550B=0 B=1.7 TUo=2.5 cm/s Uo=5 cm/s# B=0,T B=1.7,T B=0,T B=1.7,T1 376 593 437 7432 245 564 338 7573 303 481 330 6234 193 486 283 6055 223 456 251 5066 257 440 - -7 163 483 248 4828 198 484 310 5129 214 566 321 46310 205 502 314 474Mass loss, mgMass loss is almost doubledin the presence of B-fieldPbLi flowCourtesy of Dr. Andrej Shishko, Institute of Physics, LatviaRiga experiment 3/11: results•In addition to wall thinning, periodic grooves aligned with the flow direction have been observed on the Hartmann wall•Mechanism of groove formation is still not well understood•A. Shishko (Latvia): higher velocity in the surface cavities causes higher corrosion rate. The effect may be related to specimen machining •R. Moreau (France): the grooves are due to instability mechanism associated with induced electric currents crossing the interfaceCourtesy of Prof. Rene