Zero
Lattice Element Hit Error Occurs on a Rotated Lattice.
| Anomaly: | The run dies with a zero lattice
element hit error when a lattice is rotated. |
| History: | Submitted by user. |
| Versions affected: | MCNP5, MCNPX, MCNP6 |
| Impact: | Fails to run |
| Work Around: | Modify macrobody surfaces to remove chain warning. |
Steps required to reproduce this anomaly:
Note: Run this example in the RSICC release of each of these codes.
About the Input file:
A three by three xz lattice with a pitch of 20 cm. Each lattice cell is filled with an 8 cm radius sphere of water. A fixed source is volumetrically distributed through each of the nine spheres. A translation card rotates the lattice.
Note the surface definition for surface 7 appears twice. The work-around definition is commented out.
Click here to download the input file, iddt3 (2 kb).
Process to Produce Anomaly:
Verify that the surface definition for surface 7 is the : rpp -10 50 -10 10 -10 50 version of the input file.
Run the input file in MCNP5 and/or MCNPX and/or MCNP6 verify the result.
Work around:
Verify that the surface definition for surface 7 is the : rpp -9.9999 49.9999 -9.9999 9.9999 -9.9999 40.9999 version of the input file.
Click here to download the input file, iddt3a (2 kb).
Process to Demonstrate Work Around.:
Run the input file in MCNP5 and/or MCNPX and verify the result.
Run the input file in MCNP6 and verify the results.
Results obtained from our test:
MCNP6 fails. Notice the two chain errors and that 6 surfaces were deleted. A zero lattice element hit error is displayed:
With the surfaces moved, MCNP6 runs to completion:
Notice the chain errors do not appear and only 2 surfaces were deleted. Runs to completion.
