Skip to content

Commit

Permalink
Clean-up addExternalHeat.
Browse files Browse the repository at this point in the history
  • Loading branch information
Phil Ahrenkiel authored and Phil Ahrenkiel committed Dec 18, 2023
1 parent 2323921 commit 6befa22
Showing 1 changed file with 32 additions and 38 deletions.
70 changes: 32 additions & 38 deletions src/HPWHHeatSources.cc
View file
Original file line number Diff line number Diff line change
Expand Up @@ -437,10 +437,6 @@ void HPWH::HeatSource::addHeat(double externalT_C,double minutesToRun) {
if(hpwh->hpwhVerbosity >= VRB_reluctant)
hpwh->msg("Internal error: Negative runtime = %0.3f min\n",runtime_min);
#endif
// Accumulate the input & output energy
energyInput_kWh += KJ_TO_KWH(powerInput_kW * runtime_min * sec_per_min);
energyOutput_kWh += KJ_TO_KWH(heatAdded_kJ);
energyTransient_kWh = KJ_TO_KWH(powerOutput_kW * runtime_min * sec_per_min) - KJ_TO_KWH(heatAdded_kJ);
}
break;

Expand All @@ -451,13 +447,14 @@ void HPWH::HeatSource::addHeat(double externalT_C,double minutesToRun) {
runtime_min = addHeatExternal(externalT_C,minutesToRun,cap_BTUperHr,input_BTUperHr,cop);
powerInput_kW = BTUperH_TO_KW(input_BTUperHr);
powerOutput_kW = BTUperH_TO_KW(cap_BTUperHr);

energyInput_kWh += KJ_TO_KWH(powerInput_kW * runtime_min * sec_per_min);
energyOutput_kWh += KJ_TO_KWH(powerOutput_kW * runtime_min * sec_per_min);
energyTransient_kWh = 0.;
heatAdded_kJ = powerOutput_kW * runtime_min * sec_per_min;
break;
}

// Accumulate the input & output energy; find retrained transient heat
energyInput_kWh += KJ_TO_KWH(powerInput_kW * runtime_min * sec_per_min);
energyOutput_kWh += KJ_TO_KWH(heatAdded_kJ);
energyTransient_kWh = KJ_TO_KWH(powerOutput_kW * runtime_min * sec_per_min) - KJ_TO_KWH(heatAdded_kJ);
}

void HPWH::HeatSource::addTransientHeat() {
Expand Down Expand Up @@ -779,12 +776,11 @@ bool HPWH::HeatSource::isExternalMultipass() const {
}

double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,double &cap_BTUperHr,double &input_BTUperHr,double &cop) {
double heatingCapacity_kJ,heatingCapacityNeeded_kJ,deltaT_C,timeUsed_min,nodeHeat_kJperNode,nodeFrac,fractToShutOff;
double heatingCapacity_kJ,heatingCapacityNeeded_kJ,deltaT_C,timeUsed_min,fractToShutOff;
double inputTemp_BTUperHr = 0,capTemp_BTUperHr = 0,copTemp = 0;
double volumePerNode_LperNode = hpwh->tankVolume_L / hpwh->getNumNodes();
double timeRemaining_min = minutesToRun;
double maxTargetTemp_C = std::min(maxSetpoint_C,hpwh->setpoint_C);
double targetTemp_C = 0.;
double maxTargetT_C = std::min(maxSetpoint_C,hpwh->setpoint_C);
double targetT_C = 0.;
input_BTUperHr = 0;
cap_BTUperHr = 0;
cop = 0;
Expand All @@ -804,8 +800,7 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,

heatingCapacity_kJ = heatingCapacity_KW * (timeRemaining_min * sec_per_min);

targetTemp_C = calcMPOutletTemperature(heatingCapacity_KW);
deltaT_C = targetTemp_C - hpwh->tankTemps_C[externalOutletHeight];
targetT_C = calcMPOutletTemperature(heatingCapacity_KW);
} else {
//how much heat is available this timestep
getCapacity(externalT_C,hpwh->tankTemps_C[externalOutletHeight],inputTemp_BTUperHr,capTemp_BTUperHr,copTemp);
Expand All @@ -822,28 +817,26 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,

//calculate what percentage of the bottom node can be heated to setpoint
//with amount of heat available this timestep
targetTemp_C = maxTargetTemp_C;
deltaT_C = targetTemp_C - hpwh->tankTemps_C[externalOutletHeight];

targetT_C = maxTargetT_C;
}

nodeHeat_kJperNode = volumePerNode_LperNode * DENSITYWATER_kgperL * CPWATER_kJperkgC * deltaT_C;
deltaT_C = targetT_C - hpwh->tankTemps_C[externalOutletHeight];
double nodeHeat_kJ = hpwh->nodeVolume_L * DENSITYWATER_kgperL * CPWATER_kJperkgC * deltaT_C;

// Caclulate fraction of node to move
if(nodeHeat_kJperNode <= 0.) { // protect against dividing by zero - if bottom node is at (or above) setpoint, add no heat
nodeFrac = 0.;
} else {
nodeFrac = heatingCapacity_kJ / nodeHeat_kJperNode;
double nodeFrac = 0.;
if(nodeHeat_kJ > 0.) { // protect against dividing by zero - if bottom node is at (or above) setpoint, add no heat
nodeFrac = heatingCapacity_kJ / nodeHeat_kJ;
}

if(hpwh->hpwhVerbosity >= VRB_emetic) {
hpwh->msg("nodeHeat_kJperNode: %.2lf nodeFrac: %.2lf \n\n",nodeHeat_kJperNode,nodeFrac);
hpwh->msg("nodeHeat_kJ: %.2lf nodeFrac: %.2lf \n\n",nodeHeat_kJ,nodeFrac);
}

fractToShutOff = fractToMeetComparisonExternal();
if(fractToShutOff < 1. && fractToShutOff < nodeFrac && !this->isMultipass) { // circle back and check on this for multipass
if(fractToShutOff < 1. && fractToShutOff < nodeFrac && !isMultipass) { // circle back and check on this for multipass
nodeFrac = fractToShutOff;
heatingCapacityNeeded_kJ = nodeFrac * nodeHeat_kJperNode;
heatingCapacityNeeded_kJ = nodeFrac * nodeHeat_kJ;

timeUsed_min = (heatingCapacityNeeded_kJ / heatingCapacity_kJ) * timeRemaining_min;
timeRemaining_min -= timeUsed_min;
Expand All @@ -852,7 +845,7 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,
//take to heat that node from the timeRemaining
else if(nodeFrac > 1.) {
nodeFrac = 1.;
timeUsed_min = (nodeHeat_kJperNode / heatingCapacity_kJ)*timeRemaining_min;
timeUsed_min = (nodeHeat_kJ / heatingCapacity_kJ) * timeRemaining_min;
timeRemaining_min -= timeUsed_min;
}
//otherwise just the fraction available
Expand All @@ -865,16 +858,17 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,
// Track the condenser temperature if this is a compressor before moving the nodes
if(isACompressor()) {
hpwh->condenserInlet_C += hpwh->tankTemps_C[externalOutletHeight] * timeUsed_min;
hpwh->condenserOutlet_C += targetTemp_C * timeUsed_min;
hpwh->condenserOutlet_C += targetT_C * timeUsed_min;
}

// Moving the nodes down
// move all nodes down, mixing if less than a full node
for(int n = externalOutletHeight; n < externalInletHeight; n++) {
hpwh->tankTemps_C[n] = hpwh->tankTemps_C[n] * (1 - nodeFrac) + hpwh->tankTemps_C[n + 1] * nodeFrac;
hpwh->tankTemps_C[n] = (1. - nodeFrac) * hpwh->tankTemps_C[n] + nodeFrac * hpwh->tankTemps_C[n + 1];
}

//add water to top node, heated to setpoint
hpwh->tankTemps_C[externalInletHeight] = hpwh->tankTemps_C[externalInletHeight] * (1. - nodeFrac) + targetTemp_C * nodeFrac;
hpwh->tankTemps_C[externalInletHeight] = (1. - nodeFrac) * hpwh->tankTemps_C[externalInletHeight] + nodeFrac * targetT_C;

hpwh->mixTankInversions();
hpwh->updateSoCIfNecessary();
Expand All @@ -885,7 +879,7 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,
cap_BTUperHr += capTemp_BTUperHr * timeUsed_min;
cop += copTemp * timeUsed_min;

hpwh->externalVolumeHeated_L += nodeFrac * volumePerNode_LperNode;
hpwh->externalVolumeHeated_L += nodeFrac * hpwh->nodeVolume_L;

//if there's still time remaining and you haven't heated to the cutoff
//specified in shutsOff logic, keep heating
Expand All @@ -894,21 +888,21 @@ double HPWH::HeatSource::addHeatExternal(double externalT_C,double minutesToRun,
// divide outputs by sum of weight - the total time ran
// not timeRemaining_min == minutesToRun is possible
// must prevent divide by 0 (added 4-11-2023)
double timeRun = minutesToRun - timeRemaining_min;
if(timeRun > 0.)
double timeRun_min = minutesToRun - timeRemaining_min;
if(timeRun_min > 0.)
{
input_BTUperHr /= timeRun;
cap_BTUperHr /= timeRun;
cop /= timeRun;
hpwh->condenserInlet_C /= timeRun;
hpwh->condenserOutlet_C /= timeRun;
input_BTUperHr /= timeRun_min;
cap_BTUperHr /= timeRun_min;
cop /= timeRun_min;
hpwh->condenserInlet_C /= timeRun_min;
hpwh->condenserOutlet_C /= timeRun_min;
}

if(hpwh->hpwhVerbosity >= VRB_emetic) {
hpwh->msg("final remaining time: %.2lf \n",timeRemaining_min);
}
// return the time left
return timeRun;
return timeRun_min;
}

void HPWH::HeatSource::setupAsResistiveElement(int node,double Watts,int condensitySize/* = CONDENSITY_SIZE*/) {
Expand Down

0 comments on commit 6befa22

Please sign in to comment.