- #1
ethnscot
- 2
- 1
This is what I hate about MCNP, not a lot of documentation. How do I define all of a universe as a source and a tally? I have a lattice like the below code.
How do I get this code to work with tallies for positions 1,2, and 3 in the lattice; and a source for the 2's. I get the error "sampling efficiency is too low" Since, I have a very, very low efficiency I'm not sure how to fix this.
How do I get this code to work with tallies for positions 1,2, and 3 in the lattice; and a source for the 2's. I get the error "sampling efficiency is too low" Since, I have a very, very low efficiency I'm not sure how to fix this.
One That Doesn't Work:
MCNP Cell File
c Created on
901 0 999 imp:p=0 imp:e=0
902 6 -0.001205 -999 901 imp:p=0 imp:e=0
903 0 -902 u=999 lat=1 imp:p=1 imp:e=1
fill=0:2 0:8 0:4
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 1
4 2 1 1 1 1 1 1 1 1 1 1 1 1 1
904 0 -901 fill=999 imp:p=1 imp:e=1
42 0 -903 u=1 imp:p=1 imp:e=1
43 0 903 u=1 imp:p=0 imp:e=0
1 2 -0.997 -903 u=2 imp:p=1 imp:e=1
101 0 903 u=2 imp:p=0 imp:e=0
2 2 -0.997 -903 u=3 imp:p=1 imp:e=1
102 0 903 u=3 imp:p=0 imp:e=0
3 6 -0.001205 -903 u=4 imp:p=1 imp:e=1
103 0 903 u=4 imp:p=0 imp:e=0
901 rpp 0 71 0 167 0 119
902 rpp -10.0 10.0 -10.0 10.0 -10.0 10.0
903 rpp -10.1 10.1 -10.1 10.1 -10.1 10.1
999 rpp -5 76 -5 172 -5 124
c water
m2 1000 -0.111902
8000 -0.888098
c Air
m6 6000 -0.000124
7000 -0.755268
8000 -0.231781
18000 -0.012827
mode p e
sdef erg=1 par=2 eff=0.0000001 X=d1 Y=d2 Z=d3 cel=d4
si1 -10.0 10.0
sp1 0 1
si2 -10.0 10.0
sp2 0 1
si3 -10.0 10.0
sp3 0 1
si4 L (3<903<904)
sp4 1
f8:e (2<903<904)
e8 0 0.0000001 5.0
f18:e (2<903<904)
e18 0 0.0000001 5.0
nps 1000000