1. REACTOR CORE

fuel-moderator material 8 wt% uranium 
91 wt% zirconium 
1 wt% hydrogen
uranium enrichment 19.8% Uran-235
fuel element dimensions 3.75 cm in diameter 
72.24 cm in length
cladding  0.51 mm steel
active core volume  max. 49.5 cm diameter, 38.1 cm high
core loading  3 kg of uranium-235

2. REFLECTOR

material graphite with aluminum cladding
radial thickness 30.5 cm
top and bottom thickness 56 cm

3. CONSTRUCTION

reactor shielding construction  heavy and standard concrete 
6.55 m high, 6.19 m wide, 8.76 m long
reactor tank 1.98 m in diameter 
6.40 m in depth

4. SHIELDING

radial:  30.5 cm of graphite; 
45.7 cm of water 
206 cm of heavy concrete
vertical: above the core 4.90 m of water and 10.2 cm graphite; 
underneath the core 61.0 cm water, 10.2 cm graphite and at least 91 cm standard concrete

5. IRRADIATION DEVICES

(1) four beam holes 15.2 cm in diameter 
(2) one central irradiation tube (center of core) 
(3) five reflector irradiation tubes 
(4) one pneumatic transfer system (near core edge) 
(5) one thermal column with cross section 1.22x1.22 m and length 1.68 m 
(6) experimental tank with surface area 2.44x2.74 m and depth 3.66 m;
        connected to the reactor by means of a neutron radiography collimator
        0.61x0.61 m in cross section and 1.22 m long. 

6. CONTROL SYSTEM 

  • Two boron carbide control rods with electric motor and rack and pinion drive.
  • One boron carbide pulse rod with compressed air drive (5 bar).
  • Maximum reactivity insertion rate - time rate of change (excluding pulse operation ): 0.04% δk/k per second
  • Total rod worth about 4.8% δk/k.

 

7. CHARACTERISTICS IN CONTINUOUS OPERATION
Thermal power output: 250 kW
Fuel element cooling: natural convection of the tank water below 100 kW, pump circulation cooling above 100 kW
tank water cooling: heat exchanger
thermal flux:  central irradiation tube: 1x1013cm-2s-1
in the irradiation tubes: 1.7x1012 cm-2s-1
prompt temperature coefficient: -1.2x10-4 δk/k°C
mean prompt neutron lifetime: 6.0x10-5 s.

8. EIGENSCHAFTEN BEIM IMPULSBETRIEB
peak power 250 MW
prompt pulse energy yield 10 MW s
prompt pulse lifetime 40 ms
total energy yield  12 MW s
minimal period 10 ms
maximum reactivity insertion 1.6% δk/k = 2$
maximum repetition frequency  12/h
number of fissions during a pulse 3x1017
maximum fuel temperature: during the pulse 240 °C 
9 seconds after the pulse 360 °C

9. BRIEF STATISTICAL DATA
average during last 5 years  
power produced (MWh) 300
irradiation experiments 200
beam hole experiments 15
number of reactor pulses 10
number of visitors 2500