coolPlant

COOLPLANT user inputs

Name Type Variability Description/Comments
cpSched OFFAVAILONVC Start of hour schedule, hourly choice of OFF, AVAIL (default), ON.
cpTsSp TEMP Start of hour supply temp cooling setpoint, hourly variable, default 44.
cpPipeLossF number Start of phase
  • pipe "loss": heat gain equal to this fraction of largest stage <-- CHANGE **
  • capacity will be used in any subhour when any chiller runs. default .01.
cpTowi TI input time
  • subscript of [TOWERPLANT][towerplant] supporting this [COOLPLANT][coolplant]. Input as name "[cpTowerplant][cptowerplant]". RQD.
  • [COOLPLANT][coolplant] stages: 7 arrays, each input as list of up to 7 chiller names, or ALL_BUT, comma, and up to 6 names, or ALL.
  • Internally, subscripts, TI_ALLBUT, and TI_ALL are stored, with 0 after and of lists (poss garbage after TI_ALL).
cpStage1[index] TI Array [8] Start of phase defaulted by code, if NO cpStage values entered:
cpStage2[index] TI Array [8] Start of phase defaulted by code, if NO cpStage values entered:
cpStage3[index] TI Array [8] Start of phase ... stage 1: TI_ALL. stages 2-7: none(0).
cpStage4[index] TI Array [8] Start of phase ... stage 1: TI_ALL. stages 2-7: none(0).
cpStage5[index] TI Array [8] Start of phase
cpStage6[index] TI Array [8] Start of phase
cpStage7[index] TI Array [8] Start of phase
  • CAUTION: code may access stages by subscripting, assuming they follow cpStage1 in order.
  • CAUTION: code may use internal subscript 0-6 to access variables named cpStage1-7. Potentially confusing!

COOLPLANT setup time

Name Type Variability Description/Comments
ch1 TI Start of run subscript of 1st CHILLER in this COOLPLANT. Next is CHILLER.nxCh4cp.
ah1 TI Start of run subscript of 1st AH with CHW coil served by this COOLPLANT. Next is AH.ahcc.nxAh4cp.
nxCp4tp TI Start of run subscript of next COOLPLANT using same TOWERPLANT. 1st is TOWERPLANT.c1.
mwDsCoils DBL Start of run
  • MFLOW
  • sum of dsgn flows of connected CHW coils, accum by COOLCOIL::setup, for check vs pumps.
stgPPQ[index] number Array [7] Start of run
  • POWER
  • primary pump heats of stages 0-6.
stgCPQ[index] number Array [7] Start of run
  • POWER
  • condenser pump heats of stages 0-6.
stgPMw[index] number Array [7] Start of run
  • MFLOW
  • primary pump flows of stages 0-6.
stgCMw[index] number Array [7] Start of run
  • MFLOW
  • condenser (heat rejection) pump flows of stages 0-6, lb/hr
  • note there is no array of capacities cuz depend on ts and tCnd, must recompute as needed.
stgN number Start of run max+1 used stage subscript 1-7 (used stages need not be contiguous)
stgMxCap number Start of run subscript 0-6 of stage with most design power
mxCapDs DBL Start of run
  • POWER
  • design power of most powerful stage (negative)
mxPMw DBL Start of run
  • MFLOW
  • largest primary pump flow, for computing minimum delta-t at runtime
mxPMwOv DBL Start of run
  • MFLOW
  • primary pump flow w/ overrun of stage with most design power, for check vs coils
mxCondQ DBL Start of run
  • POWER
  • max design rejected heat (positive), re defaulting [TOWERPLANT][towerplant] capacity
mxCondGpm DBL Start of run
  • MFLOW
  • condenser pump flow of same stage (not verified largest), gpm: input value
qPipeLoss DBL Start of run
  • POWER
  • pipe "loss" power: [cpPipeLossF][cppipelossf] * mxCapDs. Negative.

COOLPLANT runtime: outputs to other objects

Name Type Variability Description/Comments
cpTs DBL End of subhour
  • TEMP
  • primary water supply temp to coils. cp- to not confuse with AH::ts when used re coil.
q DBL End of subhour
  • POWER
  • current primary output power to coils, for results
qTow DBL End of subhour
  • POWER
  • heat added to condenser water, incl pump heat, Btuh.
tTow DBL End of subhour
  • TEMP
  • temp of water returned from chiller condensers, avail to towerplant (not used 10-92).
mwTow DBL End of subhour
  • MFLOW
  • condenser water flow to towerplant, lb/hr. stgCMw[stgi].
  • power consumption: occurs in chillers, is posted directy to meters.
  • [COOLPLANT][coolplant] runtime: input from other objects
tCnd DBL End of subhour
  • TEMP
  • heat rejection: water temp entering chiller condensers, last used [TOWERPLANT][towerplant].tpTs.
  • also used as this cp's prior tpTs for change detection.
  • [COOLPLANT][coolplant] runtime: internal
cpClf BOO End of subhour call-flag: set nz if must call cpCompute so it can test tr, etc to see if computation needed.
cpPtf BOO End of subhour compute-flag: set if must call cpCompute and it should unconditionally recompute this plant
cpMode choice:OFFON End of subhour
  • mode this subhour: off or on: per [cpSched][cpsched]; per demand for AVAIL. Set in cpEstimate, cpCompute.
  • cpCompute next input(s), calculated at entry to tpCompute before commitment to new calculation:
qLoadNx DBL End of subhour
  • POWER
  • heat added to water by loads. Negative. Believe need in rec only for debug/reporting.
  • cpCompute current input(s), as used for current cpTs. -Nx('s) copied, after decision to calculate anew.
qLoad DBL End of subhour
  • POWER
  • load: sum of coil Btuh's, pipe loss. Negative. May be used in cpEstimate.
tr DBL End of subhour
  • TEMP
  • load: return water temp from coils, incl pipe loss, assuming no mw overrun.
stgi number End of subhour stage in use, 0-6 for cpStage1-7.
qNeed DBL End of subhour
  • POWER
  • power needed from coolPlant to deliver water at setpoint: ([cpTsSp][cptssp] - tr) * mw[stg]. negative.
cap DBL End of subhour
  • POWER
  • curr capac of stgi chillers @ ts & tCnd, Btuh, incl pump heat, set by capStg().
plr DBL End of subhour
  • FRAC
  • part load ratio
puteTs DBL End of subhour
  • TEMP
  • cpCompute's supply temp: cpTs, but not overwritten by cpEstimate, for debug aid/probes/reports.
  • runtime internal: Pr's: prior values for runtime change-detection
cpTsSpPr TEMP End of subhour for cpEstimate
cpTsEstPr TEMP End of subhour for cpEstimate
cpModePr choice:OFFON End of subhour for cpCompute
trMxPr TEMP End of subhour for cpCompute: tr-assuming-max-flow when last computed
qLoadPr number End of subhour for cpCompute
mwTowPr MFLOW End of subhour for cpCompute, set by tpCompute
tTowPr number End of subhour for cpCompute, set by tpCompute