Fix order of curve independent variables for GAHP

doc/engineering-reference/src/simulation-models-encyclopedic-reference-002/air-system-compound-component-groups.tex

@@ -2994,9 +2994,9 @@ \subsubsection{Equipment Capacity}
 \mathrm{GAHP Heating/Cooling Capacity} = \mathrm{Rated Capacity} \times \mathrm{CAPFT}
 \end{equation}
 
-The temperatures used for the equation model are the ambient air temperature ($T_{mathrm{amb}}$) and the returning (or entering) water temperature ($T_{\mathrm{ret}}$) of the load side.
+The temperatures used for the equation model are the returning (or entering) water temperature ($T_{\mathrm{ret}}$) of the load side and the ambient air temperature ($T_{mathrm{amb}}$).
 \begin{equation}
-\mathrm{CAPFT} = a_1 \times T_{\mathrm{amb}} + b_1 \times T_{\mathrm{amb}}^{2} + c_1 \times T_{\mathrm{ret}} + d_1 \times T_{\mathrm{ret}}^{2} + e_1 \times T_{\mathrm{amb}} \times T_{\mathrm{ret}} + f_1
+\mathrm{CAPFT} = a + b \times T_{\mathrm{ret}} + c \times T_{\mathrm{ret}}^{2} + d \times T_{\mathrm{amb}} + e \times T_{\mathrm{amb}}^{2} + f \times T_{\mathrm{amb}} \times T_{\mathrm{ret}}
 \end{equation}
 
 \subsubsection{Part Load Ratio}
@@ -3015,13 +3015,13 @@ \subsubsection{Fuel Use}
 \subsubsection{EIR Temperature Adjustment}
 A typical EIR temperature correction function will involve two independent temperature variables---the ambient air temperature ($T_{mathrm{amb}}$) and the returning (or entering) water temperature ($T_{\mathrm{ret}}$) of the load side. 
 \begin{equation}
-\mathrm{EIRFT} = a_2 \times Tamb + b_2 \times T_{\mathrm{amb}}^{2} + c_2 \times T_{\mathrm{ret}}^{2} + d_2 \times T_{\mathrm{ret}}^{2} + e_2 \times T_{\mathrm{amb}} \times T_{\mathrm{ret}} + f_2
+\mathrm{EIRFT} = a + b \times T_{\mathrm{ret}} + c \times T_{\mathrm{ret}}^{2} + d \times T_{\mathrm{amb}} + e \times T_{\mathrm{amb}}^{2} + f \times T_{\mathrm{amb}} \times T_{\mathrm{ret}}
 \end{equation}
 
 \subsubsection{EIR PLR Adjustment}
 The EIR PLR correction function is a cubic function that takes the PLR as the sole independent variable. For example, a potential curve can be used is like the following:  
 \begin{equation}
-\mathrm{EIRFPLR} = 0.0865 \times \mathrm{PLR}^{2} - 0.006 \times \mathrm{PLR} + 0.9814, \mathrm{for} 0.25 \leq \mathrm{PLR} \leq 1 
+\mathrm{EIRFPLR} = 0.0865 \times \mathrm{PLR}^{2} - 0.006 \times \mathrm{PLR} + 0.9814, \mathrm{for } 0.25 \leq \mathrm{PLR} \leq 1
 \end{equation}
 
 \subsubsection{Defrosting Adjustment (Heating mode only)}
@@ -3044,10 +3044,14 @@ \subsubsection{Cycling Ratio Adjustment}
 
 Please note that since the object is based on curve inputs, the user also has the flexibility of defining the curves by themselves---e.g. from the capacity function of temperature to the defrost EIR corrections. 
 
-\subsubsection{Electricty Use}
+\subsubsection{Electricity Use}
 
 The electricity use for the fuel-fired absorption heat pump is modeled using EIR (Electricity based relation) input curves. The two part of electricity use is the ``auxiliary electricity'' and the ``standby electricity'':
 \begin{equation}
-\mathrm{Electricity use} = \mathrm{Norminal Auxiliary Power} \times \mathrm{EIR}_{\mathrm{auxiliary}} + \mathrm{Electricty}_{\mathrm{Standby}},
+\mathrm{Electricity use} = \mathrm{Norminal Auxiliary Power} \times \mathrm{EIR}_{\mathrm{auxiliary}} + \mathrm{Electricity}_{\mathrm{Standby}},
 \end{equation}
-where $\mathrm{EIR}_{\mathrm{auxiliary}}$ are supplied by the curve input, and $\mathrm{Norminal Auxiliary Power}$ and $\mathrm{Electricty}_{\mathrm{Standby}}$ are supplied by the equipment standby electricity inputs. 
+Where $\mathrm{Norminal Auxiliary Power}$ and $\mathrm{Electricity}_{\mathrm{Standby}}$ are user inputs and where $\mathrm{EIR}_{\mathrm{auxiliary}}$ is a curve modifier defined as follows and involves two independent temperature variables---the ambient air temperature ($T_{mathrm{amb}}$) and the returning (or entering) water temperature ($T_{\mathrm{ret}}$) of the load side.
+
+\begin{equation}
+\mathrm{EIR}_{\mathrm{auxiliary}} = a + b \times T_{\mathrm{ret}} + c \times T_{\mathrm{ret}}^{2} + d \times T_{\mathrm{amb}} + e \times T_{\mathrm{amb}}^{2} + f \times T_{\mathrm{amb}} \times T_{\mathrm{ret}}
+\end{equation}

testfiles/PlantLoopHeatPump_Fuel-Fired.idf

@@ -275,8 +275,8 @@ HeatPump:AirToWater:FuelFired:Heating,
     NotModulated,            !- Flow Mode
     DryBulb,                 !- Outdoor Air Temperature Curve Input Variable
     EnteringCondenser,       !- Water Temperature Curve Input Variable
-    CapCurveFuncTemp,        !- Normalized Capacity Function of Temperature Curve Name
-    EIRCurveFuncTemp,        !- Fuel Energy Input Ratio Function of Temperature Curve Name
+    HeatingCapCurveFuncTemp,        !- Normalized Capacity Function of Temperature Curve Name
+    HeatingEIRCurveFuncTemp,        !- Fuel Energy Input Ratio Function of Temperature Curve Name
     EIRCurveFuncPLR,         !- Fuel Energy Input Ratio Function of PLR Curve Name
     0.2,                     !- Minimum Part Load Ratio
     1.0,                     !- Maximum Part Load Ratio
@@ -334,6 +334,24 @@ HeatPump:AirToWater:FuelFired:Heating,
     -100,                    !- Minimum Value of x
     100;                     !- Maximum Value of x
 
+!- From Table 3 in "Pathways to Decarbonization of Residential Heating", Fridlyand et al. (2021)
+  Curve:Biquadratic,
+    HeatingCapCurveFuncTemp, !- Name
+    1.011452,                !- Coefficient1 Constant
+    0.004093,                !- Coefficient2 x
+    -0.00014,                !- Coefficient3 x**2
+    0.00428,                 !- Coefficient4 y
+    -0.000086,               !- Coefficient5 y**2
+    0.00000226,              !- Coefficient6 x*y
+    -100,                    !- Minimum Value of x
+    100,                     !- Maximum Value of x
+    -30.0,                   !- Minimum Value of y
+    10.0,                    !- Maximum Value of y
+    ,                        !- Minimum Curve Output
+    ,                        !- Maximum Curve Output
+    Temperature,             !- Input Unit Type for X
+    Temperature,             !- Input Unit Type for Y
+    Dimensionless;           !- Output Unit Type
 
   Curve:Biquadratic,
     CapCurveFuncTemp,        !- Name
@@ -353,6 +371,28 @@ HeatPump:AirToWater:FuelFired:Heating,
     Temperature,             !- Input Unit Type for Y
     Dimensionless;           !- Output Unit Type
 
+!- Adapted from Table 3 in "Pathways to Decarbonization of Residential Heating", Fridlyand et al. (2021)
+!- The curve from Table 3 output an adjusted EIR and not an EIR modifier
+!- The curve from Table 3 has been renormalized at the ANSI rating conditions of 95°F return and 47°F ambient to represent an EIR modifier
+
+  Curve:Biquadratic,
+    HeatingEIRCurveFuncTemp, !- Name
+    0.559888009625229,       !- Coefficient1 Constant
+    0.0171957698511524,      !- Coefficient2 x
+    -0.0000891729967627554,  !- Coefficient3 x**2
+    -0.00464869065091091,    !- Coefficient4 y
+    0.00009648225879249,     !- Coefficient5 y**2
+    -0.0000701689154854473,  !- Coefficient6 x*y
+    -100,                    !- Minimum Value of x
+    100,                     !- Maximum Value of x
+    -30.0,                   !- Minimum Value of y
+    10.0,                    !- Maximum Value of y
+    ,                        !- Minimum Curve Output
+    ,                        !- Maximum Curve Output
+    Temperature,             !- Input Unit Type for X
+    Temperature,             !- Input Unit Type for Y
+    Dimensionless;           !- Output Unit Type
+
   Curve:Biquadratic,
     EIRCurveFuncTemp,        !- Name
     1.0,                     !- Coefficient1 Constant