Curve Tab

The description of the performance curves for the Engine Driven Air cooled chillers is listed below.

Capacity Ratio Curve	Capacity - Power Curve
Power Curve	Fuel Use Curve

back to Engine Driven Chiller top

Capacity Ratio Curve

This quadratic curve determines the ratio of available capacity to nominal capacity.

The equation for the Capacity Curve is:

Where:

y = Chiller’s available capacity to nominal capacity ratio (%)

C1 to C3 = coefficients

TempCondIn = Temperature entering the condenser (water or air temperature depending on condenser type)

TempCondInDesign = Temp Design Condenser Inlet from User input above

TempEvapOut = Temperature leaving the evaporator

TempEvapOutDesign = Temp Design Evaporator Outlet from User input above

TempRiseCoefficient = User Input from above

The curve has the following fields:

X Axis:

Y Axis: Full Capacity (%)

Curve Type: The curve is quadratic

Min / Max: Minimum and Maximum Delta T

back to Engine Driven Chiller Curve Tab top

Capacity –Power Curve (Power ratio curve)

This quadratic curve shows the percentage of full power capacity as a function of the chiller’s capacity. The equation for the Capacity-Power Curve is:

Where:

y = percentage of full power (%)

C1 to C3 = coefficients

X = percentage of full load capacity (%)

The curve has the following fields:

X Axis: Full capacity (%)

Y Axis: Full Power (%)

Curve Type: The curve is quadratic

Capacity Min / Max: Minimum and Maximum percentage of the capacity

back to Engine Driven Chiller Curve Tab top

Power Curve (Full Load Ratio)

This quadratic curve shows the fraction of full load power capacity as a function of the chiller’s Part load ratio. The equation for the Capacity-Power Curve is:

Where:

y = fraction of full power (%)

C1 to C3 = coefficients

X = part load ratio (%)

The curve has the following fields:

X Axis: Full load (%)

Y Axis: Full Power (%)

Curve Type: The curve is quadratic

Capacity Min / Max: Minimum and Maximum percentage of the load

back to Engine Driven Chiller Curve Tab top

Fuel used Curve (Fuel Input curve)

This quadratic curve determines the Ratio of Fuel Input to Cooling Part Load. The equation for the Fuel used Curve is:

Where:

y = Ratio of Fuel Input to Cooling Load Output (%)

C1 to C3 = coefficients

X = Full Load (%)

The curve has the following fields:

X Axis: Part Load (%)

Y Axis: Fuel Use (%)

Curve Type: The curve is quadratic

Full Load Min / Max: Minimum and Maximum percentage of the load to capacity

back to Engine Driven Chiller Curve Tab top