Fuel management in a LWR.

Demo of locating and swapping assemblies in a core with Cartesian geometry. Given a burnup distribution, this swaps high burnup assemblies with low ones.

Assembly selection for moving and swapping is very flexible using the ARMI API and the high-level language features of Python. This allows highly complex fuel management algorithms to be expressed and parameterized.

Because the ARMI framework does not come with a LWR global flux/depletion solver, actual flux/depletion results would need to be provided by a physics plugin before actually using ARMI to do fuel management. Thus, this example applies a dummy burnup distribution for demonstration purposes.

=========== Case Information ===========
=========== Input File Information ===========
=========== Reactor Cycle Information ===========
=========== Constructing Reactor and Verifying Inputs ===========
=========== Adding Assemblies to <Core: core id:140495782805024> ===========
=========== Verifying Assembly Configurations ===========
=========== Summarizing Source of Material Data for <Core: core id:140495782805024> ===========
=========== Applying Geometry Modifications ===========
=========== Initializing Mesh, Assembly Zones, and Nuclide Categories ===========
=========== Creating Interfaces ===========
=========== Interface Stack Summary  ===========
===========  Triggering Init Event ===========
=========== 01 - main                           Init            ===========
=========== 02 - fissionProducts                Init            ===========
=========== 03 - xsGroups                       Init            ===========
=========== 04 - history                        Init            ===========
=========== 05 - report                         Init            ===========
=========== 06 - database                       Init            ===========
=========== 07 - memoryProfiler                 Init            ===========
=========== 08 - snapshot                       Init            ===========
===========  Completed Init Event ===========

# Tell the gallery to feature the 2nd image
# sphinx_gallery_thumbnail_number = 2
import math

import matplotlib.pyplot as plt

from armi import configure
from armi.physics.fuelCycle import fuelHandlers
from armi.reactor.flags import Flags
from armi.reactor.tests import test_reactors
from armi.utils import plotting

# configure ARMI
configure(permissive=True)

o, reactor = test_reactors.loadTestReactor(inputFileName="refTestCartesian.yaml")

# Apply a dummy burnup distribution roughly in a cosine
for b in reactor.core.getBlocks(Flags.FUEL):
    x, y, z = b.spatialLocator.getGlobalCoordinates()
    d = math.sqrt(x**2 + y**2)
    b.p.percentBu = 5 * math.cos(d * math.pi / 2 / 90)

# show the initial burnup distribution
plotting.plotFaceMap(reactor.core, param="percentBu")

fuelHandler = fuelHandlers.FuelHandler(o)

candidateAssems = reactor.core.getAssemblies(Flags.FUEL)
criterion = lambda a: a.getMaxParam("percentBu")
candidateAssems.sort(key=criterion)

for num in range(12):
    # swap the 12 highest burnup assemblies with the 12 lowest burnup ones
    high = candidateAssems.pop()
    low = candidateAssems.pop(0)
    fuelHandler.swapAssemblies(high, low)

# re-filter the remaining candidates for more complex selections
candidateAssems = [a for a in candidateAssems if a.getMaxParam("percentBu") < 4.0]
for num in range(8):
    high = candidateAssems.pop()
    low = candidateAssems.pop(0)
    fuelHandler.swapAssemblies(high, low)

# show final burnup distribution
plotting.plotFaceMap(reactor.core, param="percentBu")
plt.close()