JAEA-Data/Code 2007-004 - Welcome to Research Group for ...

EV = best guess for α or 0.0 when IEVT=2
2 EVM Eigenvalue modifier for the first eigenvalue change
EV 1 = EV 0 + EVM, after the first modification, the linear or the quadratic
extrapolation is internally executed.
3 EPS Convergence criterion (accuracy desired)
(suggested value: EPS=0.0001)
4 BF Buckling factor
Normally enter 1.420892, if so the extrapolation length of group g:
δ = 0.710446 * λ
g tr,
g
ANISN computes a correction factor of the
dimensions. In the evaluation of
2
2
D g B
form for the finite transverse
B , 2 is added to the transverse dimensions.
δ g
D
g
B
2
1
=
3Σ
t,
g
⎪⎧
⎨
⎪⎩
π
2
2
( DY + 2δ
) ( DZ + 2δ
)
g
+
π
2
g
2
⎪⎫
⎬,
⎪⎭
2δ
g
≡ BF * λ
t,
g
= BF / Σ
t,
g
To evaluate B 2 without the extrapolation length 2δ g , enter BF=0.0.
Σ t,g
is a total cross-section if it is prepared by anisotropic calculation routine
ANISN or TWOTRAN, otherwise
Σ t,g is a transport cross-section, because these
cross-sections are stored in the same position in MACRO file.
5 DY Cylinder or plane height (cm) for buckling correction
DY may include extrapolation length when BF=0.0.
6 DZ Plane depth (cm) for buckling correction
DZ may include extrapolation length when BF=0.0.
7 DFM1 Transverse dimension for void streaming correction (Usually DFM1=0.0)
When a void region is included in the system, the evaluation of transverse
leakage by the buckling approximation is not suitable. A simple correction 28) is
provided by removing the angular component of transverse direction in the void
region. As this correction does not introduce the pseudo absorption due to
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