218
M. Yamanaka
(a) Fuel “F” shown in Fig. 8.1(a)
(b) Fuel “f” shown in Fig. 8.1(b)
Polyethylene (PE)
(19.25”)
Unit cell
(1/4”)
1/8”PE
1/16” EU 2
(1/8”)
Polyethylene (PE)
(596.90 mm)
20 mm Al plate
1/4”PE+19”PE (19.25”)
1/2”PE 9+19”PE
(23.5”)
Reflector 20.04”
(Lower)
Fuel 15”
(Unit cell 60 times)
Reflector 24.96”
(Upper)
Void (1.46”)
Polyethylene
(19”PE)
Unit cell
(7/16”)
1/8”PE+1/4”PE
(3/8”)
1/16” EU
(1/16”)
Polyethylene
(19”PE+1/2PE 2 = 20”)
20 mm Al plate 1/2”PE 2 (1”)
1/2”PE 5+1/8”P 5
(25/8”) + Void (1/3”)
Reflector 20.784”
(Lower)
Fuel 15.75”
(Unit cell 36 times)
Reflector 23.462”
(Upper)
Fig. 8.2 Description of fuel rods in A-core shown in Fig. 8.1 (Refs. [1, 2])
Fig. 8.3 Neutron spectra of
EE1 and E3 cores shown in
Figs. 8.1a, b, respectively
(Refs. [1, 2])
10
-3 10
-2 10
-1 10
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
0
0.01
0.02
0.03
0.04
0.05
Neutron energy [eV]
Neutron flux / lethargy [Arbitrary units]
EE1 (1/8"P60EUEU)
E3 (3/8"P36EU)