7. Assembly Parameters

This document lists all of the Assembly Parameters that are provided by the ARMI Framework and included plugins.

Assembly Parameters from Framework

Name	Description	Units
powerDecay	List of decay heats at each time step specified in decayHeatCalcTimesInSeconds setting.	W
orientation	Triple representing rotations counterclockwise around each spatial axis. For example, a hex assembly rotated by 1/6th has orientation (0,0,60.0)	degrees
arealPd	Power in assembly divided by its XY cross-sectional area. Related to PCT.	MW/m^2
buLimit	buLimit
chargeBu	Max block-average burnup in this assembly when it most recently entered the core. If the assembly was discharged and then re-charged, this value will only reflect the most recent charge.	%FIMA
chargeCycle	Cycle number that this assembly most recently entered the core. If the assembly was discharged and then re-charged, this value will only reflect the most recent charge.
chargeFis	Fissile mass in assembly when it most recently entered the core. If the assembly was discharged and then re-charged, this value will only reflect the most recent charge.	kg
chargeTime	Time at which this assembly most recently entered the core. If the assembly was discharged and then re-charged, this value will only reflect the most recent charge.	years
multiplicity	The number of physical assemblies that the associated object represents. This is typically 1, but may need to change when the assembly is moved between containers with different types of symmetry. For instance, if an assembly moves from a Core with 1/3rd symmetry into a spent-fuel pool with full symmetry, rather than splitting the assembly into 3, the multiplicity can be set to 3. For now, this is a bit of a hack to make fuel handling work; multiplicity in the 1/3 core should be 3 to begin with, in which case this parameter could be used as the primary means of handling symmetry and fractional domains throughout ARMI. We will probably roll that out once the dust settles on some of this SFP work. For now, the Core stores multiplicity as 1 always, since the powerMultiplier to adjust to full-core quantities.	None
daysSinceLastMove	daysSinceLastMove
kInf	kInf
maxDpaPeak	maxDpaPeak
maxPercentBu	maxPercentBu
numMoves	numMoves
timeToLimit	timeToLimit
detailedNDens	High-fidelity number density vector with up to thousands of nuclides. Used in high-fi depletion runs where low-fi depletion may also be occurring. This param keeps the hi-fi and low-fi depletion values from interfering. See core.p.detailedNucKeys for keys.	atoms/bn-cm
notes	A string with notes about the assembly, limited to 1000 characters. This parameter is not meant to store data. Needlessly storing large strings on this parameter for every assembly is potentially unwise from a memory perspective.	N/A
assyAxialSwellingSF	Assembly axial swelling due to stress-free swelling	mm
fuelVent	Boolean option to turn on/off vented fuel pins in TWR design	None
crCriticalFraction	The insertion fraction when the control rod assembly is in its critical configuration. Note that the default of -1.0 is a trigger for this value not being set yet.
crCurrentElevation	The current elevation of the bottom of the moveable section of a control rod assembly.	cm
crInsertedElevation	The final elevation of the bottom of the control material when fully inserted. Note that this should be considered a lower elevation than the crWithdrawnElevation by definition and modeling semantics.	cm
crRodLength	length of the control material within the control rod	cm
crWithdrawnElevation	The initial starting elevation of the moveable section of a control rod assembly when fully withdrawn. Note that this should be considered a higher elevation than the crInsertedElevation by definition and modeling semantics.	cm
THdeltaPNoGrav	?	Pa
THdeltaPPump	Pumping pressure rise required to pump the given mass flow rate through the rod bundle	Pa
THdeltaPTotal	Total pressure difference across the assembly	Pa
THcoolantOutletT	The nominal average bulk coolant outlet temperature out of the block.	°C
THmassFlowRate	The nominal assembly flow rate	kg/s
THlocalDTout	Maximum delta-Ts for outlet temperatures of all assemblies	°C
THlocalDToutFuel	Maximum delta-Ts for outlet temperatures of fuel assemblies	°C
THorificeSetting	The ratio of pressure drop over mass flow rate squared, through an orifice	Pa/$(kg/s)^2$
THorificeZone	orifice zone for assembly; should be location specific	None
type	The name of the assembly input on the blueprints input	?
nozzleType	nozzle type for assembly	None
Pos	?	?
Ring	?	?
THcoolantInletT	?	?
assemNum	?	?
axExpWorthPT	Axial swelling reactivity	pcm/%/cm^3
coolFlowingWorthPT	Flowing coolant reactivity	pcm/%/cm^3
coolWorthPT	Coolant reactivity	pcm/%/cm^3
dischargeTime	?	?
fuelWorthPT	Fuel reactivity	pcm/%/cm^3
hotChannelFactors	Definition of set of HCFs to be applied to assembly.	None
radExpWorthPT	Radial swelling reactivity	pcm/%/cm^3
structWorthPT	Structure reactivity	pcm/%/cm^3
AziMesh	?	?
RadMesh	?	?