Product tab
Nominal Effectiveness
|
Default: 90%
|
|
Typical Range: 50 to 80%
|
|
Min/Max: 0 to 100%
|
|
Units: N/A
|
This field specifies the effectiveness at design flow rate that is applied to the wet bulb depression to determine the conditions leaving the cooler. This model assumes that the effectiveness can vary with supply air flow rate. For effectiveness variation with supply air flow fraction, enter into the curves tab to customize a curve.
Recirculating Pump
Full Load Energy Rate
|
Default: 30 W
|
|
Typical Range: 0 to 50 W
|
|
Min/Max: 0 to 999,999
|
|
Units: W, hp, kW, therms, W/(m3/sec), W/gpm, W/(L/sec)
|
This numeric input field is the recirculating and spray pump electric power for the water sprayed on the coil.
Evaporative Loss and Blowdown
Drift Loss
|
Default: 0%
|
|
Typical Range: 0 to 3%
|
|
Min/Max: 0 to 100
|
|
Units: %
|
This input field can be used to model additional water consumed by the cooler from drift. Drift is water that leaves the cooling media as droplets and does not evaporate into the process air stream. For example, water may get blown off the evaporative media by winds and escape the air system. The value entered here is a simple fraction of the water consumed by the cooler for normal process evaporation. The amount of drift is this fraction times the water evaporated for the normal cooling process.
Blowdown Concentration Ratio
|
Default: 3
|
|
Typical Range: 3 to 5
|
|
Min/Max: 3 to 5
|
|
Units: N/A
|
This input field can be used to model additional water consumed by the cooler from blowdown. Blowdown is water that is intentionally drained from the coolers sump to offset the buildup of solids in the water that would otherwise occur because of evaporation. It can be characterized as the ratio of solids in the blowdown water to solids in the make-up water and is dimensionless.
Operational Limits
Max Dry Bulb Limit
|
Default: None
|
|
Typical Range: High Limit and 82 to 100°F (High Limit and 28 to 35°C)
|
|
Min/Max: -999,999 to 999,999°F
|
|
Units: °F; °C
|
This input field defines the evaporative cooler air inlet dry bulb temperature maximum limits. The evaporative cooler will be turned off when the evaporative cooler air inlet node dry bulb temperature exceeds this value.
Min Dry Bulb Limit
|
Default: None
|
|
Typical Range: Low Limit and 60 to 70°F (High Limit and 28 to 35°C)
|
|
Min/Max: -999,999 to 999,999°F
|
|
Units: °F; °C
|
This input field defines the evaporative cooler inlet node dry bulb temperature minimum limit. The evaporative cooler will be turned off when evaporator cooler air inlet dry-bulb temperature falls below this value.
Max Wet Bulb Limit
|
Default: None
|
|
Typical Range: Low Limit and 75 to 82°F (High Limit and 24 to 28°C)
|
|
Min/Max: -999,999 to 999,999°F
|
|
Units: °F; °C
|
This input field defines the evaporative cooler air inlet node air wetbulb temperature maximum limits. When the evaporative cooler air inlet node air wetbulb temperature exceeds this limit, then the evaporative cooler is turns off.