FP6 Design study "DIRACsecondary Beams"

"NUSTAR":Experiments with stored radioactive beams

Goals of Task 6:

•Research and development to handle the energy deposition of high-intensity primary

beams in the production target

•Design and prototype construction of a rotating target wheel

•Feasibility study and prototype construction of a liquid-metal target

Task 6: High-power production targets for fast-extracted beams

K.Sümmerer (GSI)

Super-FRS high-power production target: has to cover two totally different regimes:

1. Slow extraction: ≈ 1 s spills, Pmax = 12 kW (for 1012 238U ions/s)

Rotating graphite wheel

2. Fast extraction: ≈ 50 ns spills, Pmax = 12 kJ/50 ns = 240 GW!

Liquid-metal jet?

FP6 Design study "DIRACsecondary beams"Project "NUSTAR":Experiments with stored radioactive beamsTask 6: High-power production targets for fast-extracted beams

Detailed work packages:

1. 3-dim. theoretical calculations of the energy deposition, temperature and pressure in various materials

2. Technical design of a rotating graphite-wheel target3. Thermo-mechanical calculations for the final design 4. Experimental verification of these calculations5. Feasibility study and prototype construction of a liquid-metal target for fast

extraction

Milestones:

•Conceptual Design Target Wheel (month 24)•Conceptual Design Liquid-Metal Target (month 36)•Prototype Liquid-Metal Target (month 36)

Work package 1:Calculations of energy deposition etc.

1. Calculations for the slow-extraction scheme:

ANSYS Workbench B. Achenbach

2. Calculations for the fast-extraction scheme:

Solid Graphite Target:•BIG2•ANSYS•soon: LS-DYNA•future: AUTODYN

N. TahirB. AchenbachB. AchenbachCERN (R.Wilfinger et al.)

Liquid-Lithium Target:•BIG2•CFDLIB

N. TahirA. Tauschwitz

Work package 2:Engineering design of rotating wheel target

Model: PSI Target E (G. Heidenreich et al.)5 Thickness steps: 1, 2.5, 4, 6, 8 g/cm2 Graphite

Work package 3:Heat deposition in final design

40Ar 136Xe 238U

8 g/cm2 6 g/cm2 4 g/cm2

0.83 kW 6 kW 12 kW

240 ºC 540 ºC 750 ºC

1012 ions/s; 1 Hz rotation frequency, Gaussian profile with σy = 2mm

ANSYS B. Achenbach

Work package 3:Mechanical and thermal boundary conditions

Stress distribution

max. 22 MPa

Temperatures at the hub

max. 35 ºClimit: 150 ºC

Beam:1012 238U/s12 kW

ANSYS B. Achenbach

Work package 4: Experimental verification of temperature and stress

What is the limiting energy density for graphite as a fast-extraction target for high-intensity 238U beams?

ANSYS calculation for 1010 238U ions/50 ns:

P/M = 233 J/gΔT = 230 ºCσmax= 8 MPa << 40 MPa

Temperature and stress in 4 g/cm² graphite cube120 J / 50 ns gaussian beam

(sigma_x = 1 mm, sigma_y = 2 mm)

0.00E+00

2.00E+06

4.00E+06

6.00E+06

8.00E+06

1.00E+07

1.20E+07

1.40E+07

0.0 0.2 0.4 0.6 0.8 1.0

Time [s]

Str

ess

[Pa]

0

40

80

120

160

200

240

280

Tem

p [°

C]

Stress ANSYS [Pa]

Stress (T) = E * alpha (T) * (T - T_0) [Pa]

Tem p [°C]

S334: Accepted SIS experimentMeasurements of stress waves in graphitewith Laser Doppler vibrometer together with R. Wilfinger et al. (CERN)

Work package 5:Feasibility study of liquid-metal jet target

Step 1: Water Jet ModelWater test loop available, measurements have started in Nov. 2006

Step 2: Liquid-Na jetNa test loop being assembled, measurements will start in spring 2007

Step 3: Liquid-Li jetComponents are in house

Leading participant:

L.Stoppel, S.Gnieser, S.Gordeev, M.Daubner, R.Stieglitz and the KALLA team

ANL liquid Li jet: J. Nolen, C. Reed et al.

Work package 5:Feasibility study of liquid-metal jet target

Step 1: Water simulation:

Work package 5:Feasibility study of liquid-metal jet target

Outlook

To Do-list for the work packages in 2007:

1. Theoretical calculations: continue work on fast-extraction scheme (LS-DYNA,

AUTODYN)

2. Report on Technical Design of a Rotating Graphite-Wheel Target due 29-JAN-

2007; build and test prototype

3. Thermal calculations: Work package completed

4. Perform experiment S334: measure thermal stress waves for fast-extracted

SIS18 beams in graphite samples with Laser Doppler vibrometer

5. Continue feasibility studies of a liquid-metal target for fast extraction with

water and liq. Na jets.

Contributors to NUSTAR Task 6:B.Achenbach, K.-H.Behr, A.Bruenle, H.Geissel, C.Karagiannis, A.Kelic, B.Kindler, B.Lommel, K.Sümmerer, N.Tahir, M.Tomut, C.Trautmann, H.Weick, M.Winkler (GSI)C.H.M.Broeders, M.Daubner, S.Gnieser, S.Gordeev, A.Konobeev, R.Stieglitz, L.Stoppel (FZK)J.Maruhn, A.Tauschwitz (Uni Frankfurt)J.Lettry, H.Richter, R.Wilfinger (CERN)

Task 6 "NUSTAR1" Cost Table

NUSTAR1 GSI FZK

total EC Contr. total EC Contr.

Personnel 48 PM 24 PM 48 PM 24 PM

Consumables 140 k€ 70 k€

Total 462 k€ 231 k€ 492 k€ 246 k€