1. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 1 EURISOL DS PROJECT Task#2: MULTI-MW TARGET Y. Kadi (AB/ATB) European Organization for Nuclear Research, CERN CH-1211 Geneva 23, SWITZERLAND yacine.kadi@cern.ch

2. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 2 3x100 kW direct irradiation Fissile target surrounding a spallation n-source –>100 kW Solid converters (PSI-SINQ 740 kW on Pb, 570 MeV 1.3 mA / RAL-ISIS 160 kW on Ta, 800 MeV 0.2 mA / LANL-LANSCE 800 kW on SS cladded W, 800 MeV 1.0 mA ) –4 MW Liquid Hg (windowless or jet) EURISOL Target Stations

3. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 3 High-power Targetry Challenges High-power issues –Thermal management Target melting Target vaporization –Radiation Radiation protection Radioactivity inventory Remote handling –Thermal shock Beam-induced pressure waves –Material properties

4. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 4 Thermal Management: Liquid Target with window The SNS Mercury Target Harold G. Kirk et al. (BNL)

5. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 5 Thermal Management: Liquid Target with window F. Groeschel et al. (PSI)

6. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 6 Thermal Management: Liquid Target with free surface High-speed flow (2.5 m/s) permits effective heat removal BEAM DG16.5 Hg Experiments nominal volume flow 10 l/s Close to desired configuration  intermediate lowering of level  some pitting  axial asymmetry

7. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 7 Thermal Management: Target Pitting Issue ESS team has been pursuing the Bubble injection solution. SNS team has focused on Kolsterizing (nitriding) of the surface solution. SNS team feels that the Kolsterized surface mitigates the pitting to a level to make it marginally acceptable. Further R&D is being pursued. After 100 pulses at 2.5 MW equivalent intensity Before Harold G. Kirk et al. (BNL)

8. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 8 Thermal Management: radiation cooled rotating toroidal target toroid at 2300 K radiates heat to water-cooled surroundings rotating toroid proton beam solenoid magnet toroid magnetically levitated and driven by linear motors R.Bennett, B.King et al. Distribute the energy deposition over a larger volume Similar a rotating anode of a X-ray tube

9. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 9 Thermal Management: JET J.Lettry et al. (CERN) TT2A

10. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 10 Thermal Management: Hg- JET tests –BNL&ISOLDE: proton induced shocks –CERN at GHMFL: MHD –no observation of combined effects of proton induced shocks and MHD –one order off nominal parameters ISOLDEGHMFLBNLTT2ANuFact p+/pulse3 10 13 ----0.4 10 13 2.5 10 13 3 10 13 B [T]---20---1520 Hg targetstatic15 m/s jet (d=4mm) 2 m/s jet20 m/s/ jet20 m/s jet (d=10mm) DONE OPTIONDESIGN

11. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 11 Radiation Management The SNS Target Station Core Vessel water cooled shielding Core Vessel Multi- channel neutron guide flange Outer Reflector Plug Target Inflatable seal Target Module with jumpers Moderators

12. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 12 Radiation Management

13. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 13 Radiation Management The JPARC Kaon Target Concrete shield Concrete shield block Service space: 2m(W)  1m(H) Beam ~10m ~18m T1 container Iron shield2m2m Water pump

14. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 14 Thermal Shock When the energy deposition time frame is on the order off or less than the energy deposition dimensions divided by the speed of sound then pressure waves generation can be an important issue. Time frame = beam spot size/speed of sound Illustration Time frame = 1cm / 5x10 3 m/s = 2 µs

15. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 15 Thermal Shock Stress = Y  T U / C V Where Y = Material modulus  T = Coefficient of Thermal Expansion U = Energy deposition C V = Material heat capacity When the pressure wave amplitude exceeds material tensile strength then target rupture can occur. This limit is material dependant.

16. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 16 Objectives The objective is to perform the technical preparative work and demonstration of principle for a high power target station for production of beams of fission fragments using the mercury proton to neutron converter-target and cooling technology similar to those under development by the spallation neutron sources, accelerator driven systems and the neutrino factories. This high power target that will make use of innovative concepts of advanced design can only be done in a common effort of several European Laboratories within the three communities and their proposed design studies. In this study emphasis is put on the most EURISOL specific part a compact window or windowless liquid-metal converter-target itself while the high power design of a number of other more conventional aspects are taken from the studies in the other EURISOL tasks or even in other networks like ADVICES, IP-EUROTRANS. TASK #2 – Multi-MW Target

17. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 17 P4 – CERN P18 – PSI Switzerland P19 – IPUL Latvia C5 – ORNL USA ParticipantsContributor TASK #2 – Multi-MW Target

18. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 18 TASK #2 – Multi-MW Target

19. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 19 Description of work The task will be accomplishment through detailed engineering and theoretical work, off line and on-line testing of the different subsystems as seen from the following 5 subtasks:  Engineering study of the thermal hydraulics, fluid dynamics and construction materials of a liquid-metal converter (window/windowless or jet);  Study of an innovative waste management in the liquid Hg-loop e.g. by means of Hg distillation;  Engineering design and construction of a functional Hg-loop;  Off-line testing and validation of the thermal hydraulics and fluid dynamics;  Engineering design of the entire target station and its handling method. TASK #2 – Multi-MW Target

20. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 20 TASK #2 – Multi-MW Target

21. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 21 Main goals for the first 12-15 months  Provide a first technical design of the liquid Hg proton-to-neutron converter (output to tasks 4 and 5)  Provide a status report on optimum method for continuous extraction of radioisotopes  Provide a preliminary engineering design and cost evaluation of the liquid Hg test loop  Initiate technical study on the integration of the entire target station TASK #2 – Multi-MW Target

22. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 22 Engineering Study of the liquid metal converter  Definition of the main parameters (neutron flux angular and energy distributions, radiation damage, heat deposition, spallation product distributions) as a function of energy (1 – 3 GeV) and type of incident particle (p or d)  Establishment of the operation modes (Hg flow rates, cavitation limits, thermo-mechanical behaviour of the structures under normal operating conditions)  Evaluation of the feasibility of a windowless configuration Breakdown of work (per sub-task)

23. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 23 Innovative waste management in the liquid Hg loop  List of radioisotopes to be extracted  Literature research on the behaviour of these isotopes in Hg and appropriate extraction methods  Theoretical prediction of the chemical behaviour of the isotopes of interest using the MIEDEMA model  Selection of the best method of separation Breakdown of work (per sub-task)

24. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 24 Engineering design and construction of a functional liquid Hg loop  Evaluation of the optimal engineering design of the liquid Hg loop components (electro-magnetic pumps, flow meters, piping, diagnostics and controls)  Design of the experimental Hg loop for tests of pump and other components Engineering design of the entire target station  Initiate technical study on the fission target integration  Initiate technical study of the target enclosure and front end (HV platform)  Initiate technical study of the remote handling equipment Breakdown of work (per sub-task)

25. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 25 TASK #2 – Multi-MW Target 1st year planning

26. EURISOL DS Target Meeting, CERN, CHY.KADIMarch 10-11, 2005 26 TASK #2 – Multi-MW Target Conclusions New physics opportunities are establishing the case for the development of new high-power proton drivers. High-power targets are necessary for the exploitation of these new machines. Target systems have been developed for the initial 1MW class machines, but are as yet unproven. No convincing solution exists as yet for the envisioned 4 MW class machines. A world wide R&D effort is under way to develop new high-power targets.