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updated documentation and removed some unncessary vars

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Bryan Herman 2014-09-09 11:51:52 -04:00
parent d1e46a22ec
commit d26b2da8bc
4 changed files with 97 additions and 57 deletions
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136
docs/source/usersguide/input.rst
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@ -1238,14 +1238,26 @@ Currently, it allows users to accelerate fission source convergence during
inactive neutron batches. To run CMFD, the ``<run_cmfd>`` element in
``settings.xml`` should be set to "true".
``<active_flush>`` Element
--------------------------
``<atoli>`` Element
--------------------
The ``<active_flush>`` element controls the batch where CMFD tallies should be
reset. CMFD tallies should be reset before active batches so they are accumulated
without bias.
The ``<atoli>`` element specifies the absolute inner tolerance on the Gauss-Seidel
when performing CMFD calculations. It is only used in the standalone CMFD solver
and not when PETSc is active.
*Default*: 1.e-10
``<balance>`` Element
-------------------
The ``<balance>`` element controls whether exact neutron balance should be enforced
from CMFD tallies before creating CMFD matrices. This changes effective downscatter
cross section and thermal flux to create exact balance. It should be noted that
this option has led to instabilities when performing CMFD. It can be turned on
with "true" and off with "false".
*Default*: false
*Default*: 0
``<begin>`` Element
-------------------
@ -1268,7 +1280,25 @@ The ``<display>`` element sets one additional CMFD output column. Options are:
* "source" - prints the RMS [%] between the OpenMC fission source and CMFD
fission source.
*Default*: None
*Default*: balance
``<dhat_reset>`` Element
-------------------
The ``<dhat_reset>`` element controls whether dhat nonlinear CMFD parameters
should be reset to zero before solving CMFD eigenproblem. It can be turned on with
"true" and off with "false".
*Default*: false
``<downscatter>`` Element
-------------------
The ``<downscatter>`` element controls whether an effective downscatter cross
section should be used when using 2-group CMFD. It can be turned on with "true"
and off with "false".
*Default*: false
``<feedback>`` Element
----------------------
@ -1279,25 +1309,6 @@ It can be turned on with "true" and off with "false".
*Default*: false
``<inactive>`` Element
----------------------
The ``<inactive>`` element controls if cmfd tallies should be accumulated
during inactive batches. For some applications, CMFD tallies may not be
needed until the start of active batches. This option can be turned on
with "true" and off with "false"
*Default*: true
``<inactive_flush>`` Element
----------------------------
The ``<inactive_flush>`` element controls when CMFD tallies are reset during
inactive batches. The integer set here is the interval at which this reset
occurs. The amout of resets is controlled with the ``<num_flushes>`` element.
*Defualt*: 9999
``<ksp_monitor>`` Element
-------------------------
@ -1305,9 +1316,16 @@ The ``<ksp_monitor>`` element is used to view the convergence of linear GMRES
iterations in PETSc. This option can be turned on with "true" and turned off
with "false".
*Default*: false
``<ktol>`` Element
--------------------
The ``<ktol>`` element specifies the tolerance on the eigenvalue when performing
CMFD power iteration.
*Default*: 1.e-8
``<mesh>`` Element
------------------
@ -1376,14 +1394,6 @@ not impact the calculation.
*Default*: 1.0
``<num_flushes>`` Element
-------------------------
The ``<num_flushes>`` element controls the number of CMFD tally resets that
occur during inactive CMFD batches.
*Default*: 9999
``<power_monitor>`` Element
---------------------------
@ -1392,20 +1402,21 @@ This option can be turned on with "true" and turned off with "false".
*Default*: false
``<rtoli>`` Element
--------------------
The ``<rtoli>`` element specifies the relative inner tolerance on the Gauss-Seidel
when performing CMFD calculations. It is only used in the standalone CMFD solver
and not when PETSc is active.
*Default*: 1.e-5
``<run_adjoint>`` Element
-------------------------
The ``<run_adjoint>`` element can be turned on with "true" to have an adjoint
calculation be performed on the last batch when CMFD is active.
*Default*: false
``<snes_monitor>`` Element
--------------------------
The ``<snes_monitor>`` element is used to view the convergence of the nonlinear SNES
function in PETSc. This option can be turned on with "true" and turned off with "false".
calculation be performed on the last batch when CMFD is active. OpenMC should be
compiled with PETSc when using this option.
*Default*: false
@ -1418,6 +1429,41 @@ By setting "power", power iteration is used and by setting "jfnk", JFNK is used.
*Default*: power
``<shift>`` Element
--------------------
The ``<shfit>`` element specifies an optional Wielandt shift parameter for
accelerating power iterations. It can only be used when PETSc is not active.
It is by default very large so the impact of the shift is effectively zero.
*Default*: 1e6
``<spectral>`` Element
--------------------
The ``<spectral>`` element specifies an optional spectral radius that can be set to
accelerate the convergence of Gauss-Seidel iterations during CMFD power iteration
solve. Note this is only used in the standalone CMFD solver and does not affect
the calculation when PETSc is active.
*Default*: power
``<stol>`` Element
--------------------
The ``<stol>`` element specifies the tolerance on the fission source when performing
CMFD power iteration.
*Default*: 1.e-8
``<tally_reset>`` Element
--------------------
The ``<tally_reset>`` element contains a list of batch numbers in which CMFD tallies
should be reset.
*Default*: None
``<write_matrices>`` Element
----------------------------