Merge pull request #10650 from NREL/fixVRFOUfanCycling

fix VRFFluidTCtrl OU Fan Power not considering system cycling
NREL · Sep 12, 2024 · 6ebeecd · 6ebeecd · nrel-bot-2c · Sep 12, 2024
2 parents b723d7b + b52bc04
commit 6ebeecd
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Showing 2 changed files with 7 additions and 5 deletions.
diff --git a/src/EnergyPlus/HVACVariableRefrigerantFlow.cc b/src/EnergyPlus/HVACVariableRefrigerantFlow.cc
@@ -11489,9 +11489,9 @@ void VRFCondenserEquipment::CalcVRFCondenser_FluidTCtrl(EnergyPlusData &state, c
         Ncomp *= CyclingRatio;
         Q_h_OU *= CyclingRatio;
         this->CompActSpeed = max(CompSpdActual, 0.0);
-        this->Ncomp = max(Ncomp, 0.0) / this->EffCompInverter; // 0.95 is the efficiency of the compressor inverter, can come from IDF //@minor
-        this->OUFanPower = this->RatedOUFanPower;              //@ * pow_3( CondFlowRatio )
-        this->VRFCondCyclingRatio = CyclingRatio;              // report variable for cycling rate
+        this->Ncomp = max(Ncomp, 0.0) / this->EffCompInverter;   // 0.95 is the efficiency of the compressor inverter, can come from IDF //@minor
+        this->OUFanPower = this->RatedOUFanPower * CyclingRatio; //@ * pow_3( CondFlowRatio )
+        this->VRFCondCyclingRatio = CyclingRatio;                // report variable for cycling rate
 
         Tdischarge = this->CondensingTemp; // outdoor unit condensing temperature
         this->CoolingCapacity =
@@ -11719,7 +11719,7 @@ void VRFCondenserEquipment::CalcVRFCondenser_FluidTCtrl(EnergyPlusData &state, c
         // Key outputs of this subroutine
         this->CompActSpeed = max(CompSpdActual, 0.0);
         this->Ncomp = max(Ncomp, 0.0) / this->EffCompInverter;
-        this->OUFanPower = this->RatedOUFanPower;
+        this->OUFanPower = this->RatedOUFanPower * CyclingRatio;
         this->VRFCondCyclingRatio = CyclingRatio;
 
         Tsuction = this->EvaporatingTemp; // Outdoor unit evaporating temperature

diff --git a/tst/EnergyPlus/unit/HVACVariableRefrigerantFlow.unit.cc b/tst/EnergyPlus/unit/HVACVariableRefrigerantFlow.unit.cc
@@ -13324,7 +13324,9 @@ TEST_F(EnergyPlusFixture, VRF_FluidTCtrl_ReportOutputVerificationTest)
     EXPECT_NEAR(125.2573, thisFan->totalPower, 0.0001);
     EXPECT_NEAR(thisDXCoolingCoil.TotalCoolingEnergyRate, (thisVRFTU.TotalCoolingRate + thisFan->totalPower), 0.0001);
     EXPECT_NEAR(0.3682, state->dataHVACVarRefFlow->VRF(1).VRFCondCyclingRatio, 0.0001);
-    EXPECT_NEAR(state->dataHVACVarRefFlow->VRF(1).OUFanPower, state->dataHVACVarRefFlow->VRF(1).RatedOUFanPower, 0.0001);
+    EXPECT_NEAR(state->dataHVACVarRefFlow->VRF(1).OUFanPower,
+                state->dataHVACVarRefFlow->VRF(1).RatedOUFanPower * state->dataHVACVarRefFlow->VRF(1).VRFCondCyclingRatio,
+                0.0001);
 }
 
 // Test for #7648: HREIRFTHeat wrongly used HRCAPFTHeatConst. Occurs only if you have Heat Recovery