TECHNISCHEUNIVERSITÄTMÜNCHEN

Performance of the new high flux neutron source FRM-II

IGORR10, Gaithersburg, 13. September 2005

PhysicsDepartment

FRM-II

Winfried Petry, Technische Universität München

29. April 1996 1st nuclear license

1. August 1996 begin of construction

13. October 1997 2nd nuclear license

2. May 2003 3rd nuclear license

2. March 2004 first neutrons

21. October 2004 commissioning finished, 52 full power days of

20 MWatt

December 2004 1st Proposal round

29. April 2005 begin routine operation at 20 MWatt

August 2005 2nd proposal round

today 3rd cycle finished,

FRM-II has started its routine operation !

Neutrons, how & where?

FRM-II, the principle

concretet

Radius

20 MW(8 kg 235U)

D2O H2O

Fuel element

control rodBeryllium zone

cooling gap

fuel plate

channel for fuel element

outer tube of fuel element

inner tube of fuel element

8 kg 235Uranium

52 days fuel cycle

2.5

243 mm

229 mm

130 mm

118 mmaktive Zone44.50

2.5

Unperturbed flux distribution in FRM II

high

[cm

]

radius [cm]

cold-, hot-source, converter, beam tubes cause depression

flux depression by 20% 6.4 –6.5 x 1014 n/cm2s at beam hole positions

Cut through the reactor containment

cold neutrons

neutron guide

fast neutronstumor therapyradiology

hot neutrons

thermal neutrons

fission products

ultra cold neutrons

thermal positrons

Neutron guide hall

atom egg neutron guide hall experimental hall

second neutron guide hall in construction

120

60 60 50 50 60 60

170

NL 1 NL 2 NL 3 NL 4 NL 5 NL 6

NL

2a-

uN

L 2

a-o

NL

2b

NL

3b

NL

3c

NL

3a

NL

4b

NL

4a

NL

5a

NL

5b

Neutron guides at SR-1

Schanzer, Borchert

NL

5a

NL

6b

NL

6b

create guide end positions !!!

Neutron guide system

NL 1 NL 2c NL 2a

NL 2b

NL 3a

NL 3bNL 4aNL 4b

NL 5aNL 5bNL 6b

NL 6a

SR 8bSR 8a

SR 5a

SR 5b SR 2

Tunnel

Kasematte

1718

19

2021

12

3

4

56

7

89

10

11

12

14

13

1516

Instrumente:1. MatSci-R 5. Mephisto 9. SANS-1 13. Reflektometer 17. PANDA 21. RESI

2. NSE 6. KWS-3 10. PGA 14. RSSM 18. thermisches TOF

3. TOF TOF 7. KWS-2 11. RESEDA 15. DNS 19. TAS-NSRE

4. REFSANS 8. KWS-1 12. NOSPEC 16. MIRA 20. SPODI

Proofs ?

Anisotropic power density in FRM-II fuel element

Comparison of power densities at different heights in the fuel element after two days at about 50 kWatt thermal power, recalculated and by measuring fission product activities some days after operation. Densities are measured and calculated at an outer segment (thickness 13 mm) as function of the azimuthal angle. A dip in the power density (arrow) is clearly visible near to the azimuthal position of the cold source (center at 98°).

0 50 100 150 200 250 300 350

0,9

1,0

1,1

1,2

1,3

1,4

1,5

1,6

1,7

1,8

Y Ax

is Ti

tle

X Axis Title

1,8

1,7

1,6

1,5

1,4

1,3

1,2

1,1

1,0

0,9

0 50 100 150 200 250 300 350

azimuthal angle [degrees]

po

we

r d

en

sity

[re

lativ

e u

nits

]

20 cmbelowmid plane

mid plane

20 cmabovemid plane

140La 487 keV activity

140La 1595 keV activity

132I 667 keV activity

active core region

collimator detector

Measurement setup

real rod position in very good agreement with 2d-calculation

element provides 52 days + maximal 10 extra days

control rod position

Vertical beam divergence NL1

Karl Zeitelhack

vertical inhomogenityof cold source

Twisted Neutron guide NL2b

Karl Zeitelhack

twisted guide elementtorsion: 2,5° / m

twisted guide vacuum tube

Differential neutron flux at exit of NL2b

Karl Zeitelhack

int. = 1,8x109 n/cm2/s extrapolated to 20MW reactor power

positions

Results

Karl Zeitelhack

Investigation of selected, characteristic neutron guides

Measurement of integral and differential neutron flux NL1: int. = 9,8 109 n/cm2/s (extrapolated to 20MW) ;

NL2b: int. = 1,8 109 n/cm2/s ´´

NL6a: int. = 4,9 109 n/cm2/s ´´

Horizontal and vertical beam divergence, „effective“ reflectivityresults consistent with coatingsinhomogenity of cold source masks divergence distributions

Simulation Calculations based on MCNP + McStasexperimental results in good agreement with simulation

guides under study have good qualityreliable predictions based on simulation calculation feasibletwisted guide: phase space turn confirmed, but clearly needs further investigation

Innovative instrumentation !

First generation of instruments at FRM II

Irradiation facilities Operator

rapid pneumatic irradiation system ttrans ~ 250 ms TUM chemistrypneumatic rabbit system ttrans ~ 5 - 10 s TUM FRM-IIhydraulic rabbit system ttrans > 10 s TUM FRM-IIirradiation position in control rod fast TUM FRM-IIsilicon doping facility 20 cm, length 50 cm TUM FRM-II

Clinical tumor therapy

MeV neutrons TUM medicine

Radio- and tomographywith thermal neutrons TUM physicswith fast neutrons MeV neutrons TUM chemistryprompt gamma analisys Uni Cologne

Diffractometers

material diffractometer HMI Berlinpowder diffractometer TH Darmstadt/LMU Munichthermal single crystal diffractometer Uni Augsburg/LMU Munichhot single crystal diffractometer RWTH Aachenreflectometer for biology GKSS Geesthacht/LMU Munichreflectometer for hard matter MPG Stuttgart

First generation of instrumentation at FRM II

Spectrometer Operator

resonance spin-echo spectrometer TUM physicsback scattering spectrometer FZ-Jülichcold time-of-flight spectrometer TUM physicscold triple-axis-spectrometer TU Dresden/TUM physicsthermal triple-axis-spectrometer Uni Göttingen/TUM physicspolarised triple-axis-spectrometer MPG Stuttgart

Positron source Uni German army

Fundamental researchbeam for nuclear physics TUM physicsbeam for optical experiments TUM physics

Under construction & futuresmall angle camera SANS-1 TUM/Uni Göttingen/GKSS7 instruments from FZ-Jülich FZ-Jülich 3 small angle cameras diffuse scattering spin echo spectrometer high intensity reflectometer thermal inelastic TOF spectrometer bio diffractometer TUM physicsMunich accelerator for fission products (MAFF) MLL Munichultra cold neutrons MLL Munich

4 piston engine driven at 600 rpm

time resolution 1 ms

Schillinger, Brunner, Calzada, FRM-II

Neutrons have wavelength

Bragg equation

n = 2d sin

detector

d

internal stress

d

dE

Optimisation of a crankshaft

Mayer, Achmus, Pyzalla, Reimers - HMI, BMW

0,0 0,5 1,0 1,5 2,0 2,5 3,0 3,5 4,0 4,5 5,0 5,5 6,0 6,5 7,0 7,5

-600

-400

-200

0

200

400

8 kN rolling force

19 kN rolling force

distance from the surface [mm]

axi

al- r

adia

l [M

Pa]

neutrons in the heart

of a university campus