DEHUMIDIFIER:DESICCANT:NOFANS
This object models a solid desiccant dehumidifier. The process air stream is the air which is dehumidified. The regeneration air stream is the air which is heated to regenerate the desiccant. This object determines the process air outlet conditions, the load on the regeneration heating coil, the electric power consumption for the wheel rotor motor, and the regeneration air fan mass flow rate. All other heat exchangers are modeled as separate objects connected to the inlet and outlet nodes of the dehumidifier. The solid desiccant dehumidifier is typically used in an AirLoopHVAC:OutdoorAirSystem, but can also be specified in any AirLoopHVAC.
Name
Availability Schedule Name
Type: list of objects
(
SCHEDULE:COMPACT,
SCHEDULE:YEAR,
EXTERNALINTERFACE:FUNCTIONALMOCKUPUNITIMPORT:TO:SCHEDULE,
SCHEDULE:CONSTANT,
SCHEDULE:FILE or
EXTERNALINTERFACE:SCHEDULE)
Availability schedule name for this system. Schedule value > 0 means the system is available. If this field is blank, the system is always available.
Process Air Inlet Node Name
Type: node
This is the node entering the process side of the desiccant wheel.
Process Air Outlet Node Name
Type: node
This is the node leaving the process side of the desiccant wheel.
Regeneration Air Inlet Node Name
Type: node
This is the node entering the regeneration side of the desiccant wheel after the regeneration coil.
Regeneration Fan Inlet Node Name
Type: node
Node for air entering the regeneration fan, mass flow is set by the desiccant dehumidifier module.
Control Type
Type: choice
(LeavingMaximumHumidityRatioSetpoint or SystemNodeMaximumHumidityRatioSetpoint)
Type of setpoint control: LeavingMaximumHumidityRatioSetpoint means that the unit is controlled to deliver air at the Leaving Max Humidity Ratio Setpoint (see below), SystemNodeMaximumHumidityRatioSetpoint means that the leaving humidity ratio setpoint is the System Node Humidity Ratio Max property of the Process Air Outlet Node. A Setpoint object must be used to control this setpoint. Both control types use bypass dampers to prevent over drying.
Leaving Maximum Humidity Ratio Setpoint
Type: real number
Fixed setpoint for maximum process air leaving humidity ratio Applicable only when Control Type = LeavingMaximumHumidityRatioSetpoint.
Unit: kgWater/kgDryAir
Nominal Process Air Flow Rate
Type: real number
Process air flow rate at nominal conditions
Unit: m3/s
Nominal Process Air Velocity
Type: real number
Process air velocity at nominal flow When using Performance Model Type of Default, must be 2.032 to 4.064 m/s (400 to 800 fpm)
Unit: m/s
Maximum: 6
Rotor Power
Type: real number
Power input to wheel rotor motor
Unit: W
Minimum: 0.0
Regeneration Coil Object Type
Type: choice
(Coil:Heating:Electric, Coil:Heating:Fuel, Coil:Heating:Water or Coil:Heating:Steam)
Heating coil type works with gas, electric, hot water and steam heating coils
Regeneration Coil Name
Type: list of objects
(
COIL:HEATING:WATER,
COIL:HEATING:ELECTRIC,
COIL:HEATING:FUEL or
COIL:HEATING:STEAM)
Name of heating coil object for regeneration air
Regeneration Fan Object Type
Type: choice
(Fan:SystemModel, Fan:VariableVolume or Fan:ConstantVolume)
Type of fan object for regeneration air. When using the Default Performance Model Type (see below), only Fan:VariableVolume or Fan:SystemModel are valid.
Regeneration Fan Name
Type: list of objects
(
FAN:CONSTANTVOLUME or
FAN:VARIABLEVOLUME)
Name of fan object for regeneration air
Performance Model Type
Type: choice
(Default or UserCurves)
Specifies whether the default performance model or user-specified curves should be used to model the performance. The default model is a generic solid desiccant wheel using performance curves of the form: curve = C1 + C2*edb + C3*edb**2 + C4*ew + C5*ew**2 + C6*vel + C7*vel**2 + C8*edb*ew + C9*edb**2*ew**2 + C10*edb*vel + C11*edb**2*vel**2 + C12*ew*vel + C13*ew**2*vel**2 + C14*ALOG(edb) + C15*ALOG(ew) + C16*ALOG(vel) edb = process entering dry-bulb temperature [C] ew = process entering humidity ratio [kgWater/kgDryAir] vel = process air velocity [m/s] If UserCurves are specified, then performance is calculated as follows: Leaving Dry-Bulb = (Leaving Dry-Bulb fTW Curve) * (Leaving Dry-Bulb fV Curve) Leaving Humidity Ratio = (Leaving Humidity Ratio fTW Curve) * (Leaving Humidity Ratio fV Curve) Regen Energy = (Regen Energy fTW Curve) * (Regen Energy fV Curve) Regen Velocity = (Regen Velocity fTW Curve) * (Regen Velocity fV Curve)
Leaving Dry-Bulb Function of Entering Dry-Bulb and Humidity Ratio Curve Name
Type: list of objects
(
CURVE:CUBICLINEAR,
CURVE:BICUBIC,
CURVE:QUADRATICLINEAR,
TABLE:LOOKUP,
CURVE:FANPRESSURERISE or
CURVE:BIQUADRATIC)
Leaving dry-bulb of process air as a function of entering dry-bulb and entering humidity ratio, biquadratic curve curve = C1 + C2*edb + C3*edb**2 + C4*ew + C5*ew**2 + C6*edb*ew edb = process entering dry-bulb temperature [C] ew = process entering humidity ratio [kgWater/kgDryAir]
Leaving Dry-Bulb Function of Air Velocity Curve Name
Type: list of objects
(
CURVE:CUBIC,
CURVE:EXPONENTIALDECAY,
CURVE:FUNCTIONAL:PRESSUREDROP,
CURVE:SIGMOID,
CURVE:RECTANGULARHYPERBOLA2,
CURVE:DOUBLEEXPONENTIALDECAY,
TABLE:LOOKUP,
CURVE:RECTANGULARHYPERBOLA1,
CURVE:QUARTIC,
CURVE:EXPONENT,
CURVE:QUADRATIC,
CURVE:EXPONENTIALSKEWNORMAL or
CURVE:LINEAR)
Leaving dry-bulb of process air as a function of air velocity, quadratic curve. curve = C1 + C2*v + C3*v**2 v = process air velocity [m/s]
Leaving Humidity Ratio Function of Entering Dry-Bulb and Humidity Ratio Curve Name
Type: list of objects
(
CURVE:CUBICLINEAR,
CURVE:BICUBIC,
CURVE:QUADRATICLINEAR,
TABLE:LOOKUP,
CURVE:FANPRESSURERISE or
CURVE:BIQUADRATIC)
Leaving humidity ratio of process air as a function of entering dry-bulb and entering humidity ratio, biquadratic curve curve = C1 + C2*edb + C3*edb**2 + C4*ew + C5*ew**2 + C6*edb*ew edb = process entering dry-bulb temperature [C] ew = process entering humidity ratio [kgWater/kgDryAir]
Leaving Humidity Ratio Function of Air Velocity Curve Name
Type: list of objects
(
CURVE:CUBIC,
CURVE:EXPONENTIALDECAY,
CURVE:FUNCTIONAL:PRESSUREDROP,
CURVE:SIGMOID,
CURVE:RECTANGULARHYPERBOLA2,
CURVE:DOUBLEEXPONENTIALDECAY,
TABLE:LOOKUP,
CURVE:RECTANGULARHYPERBOLA1,
CURVE:QUARTIC,
CURVE:EXPONENT,
CURVE:QUADRATIC,
CURVE:EXPONENTIALSKEWNORMAL or
CURVE:LINEAR)
Leaving humidity ratio of process air as a function of process air velocity, quadratic curve. curve = C1 + C2*v + C3*v**2 v = process air velocity [m/s]
Regeneration Energy Function of Entering Dry-Bulb and Humidity Ratio Curve Name
Type: list of objects
(
CURVE:CUBICLINEAR,
CURVE:BICUBIC,
CURVE:QUADRATICLINEAR,
TABLE:LOOKUP,
CURVE:FANPRESSURERISE or
CURVE:BIQUADRATIC)
Regeneration energy [J/kg of water removed] as a function of entering dry-bulb and entering humidity ratio, biquadratic curve curve = C1 + C2*edb + C3*edb**2 + C4*ew + C5*ew**2 + C6*edb*ew edb = process entering dry-bulb temperature [C] ew = process entering humidity ratio [kgWater/kgDryAir]
Regeneration Energy Function of Air Velocity Curve Name
Type: list of objects
(
CURVE:CUBIC,
CURVE:EXPONENTIALDECAY,
CURVE:FUNCTIONAL:PRESSUREDROP,
CURVE:SIGMOID,
CURVE:RECTANGULARHYPERBOLA2,
CURVE:DOUBLEEXPONENTIALDECAY,
TABLE:LOOKUP,
CURVE:RECTANGULARHYPERBOLA1,
CURVE:QUARTIC,
CURVE:EXPONENT,
CURVE:QUADRATIC,
CURVE:EXPONENTIALSKEWNORMAL or
CURVE:LINEAR)
Regeneration energy [J/kg of water removed] as a function of process air velocity, quadratic curve. curve = C1 + C2*v + C3*v**2 v = process air velocity [m/s]
Regeneration Velocity Function of Entering Dry-Bulb and Humidity Ratio Curve Name
Type: list of objects
(
CURVE:CUBICLINEAR,
CURVE:BICUBIC,
CURVE:QUADRATICLINEAR,
TABLE:LOOKUP,
CURVE:FANPRESSURERISE or
CURVE:BIQUADRATIC)
Regeneration velocity [m/s] as a function of entering dry-bulb and entering humidity ratio, biquadratic curve curve = C1 + C2*edb + C3*edb**2 + C4*ew + C5*ew**2 + C6*edb*ew edb = process entering dry-bulb temperature [C] ew = process entering humidity ratio [kgWater/kgDryAir]
Regeneration Velocity Function of Air Velocity Curve Name
Type: list of objects
(
CURVE:CUBIC,
CURVE:EXPONENTIALDECAY,
CURVE:FUNCTIONAL:PRESSUREDROP,
CURVE:SIGMOID,
CURVE:RECTANGULARHYPERBOLA2,
CURVE:DOUBLEEXPONENTIALDECAY,
TABLE:LOOKUP,
CURVE:RECTANGULARHYPERBOLA1,
CURVE:QUARTIC,
CURVE:EXPONENT,
CURVE:QUADRATIC,
CURVE:EXPONENTIALSKEWNORMAL or
CURVE:LINEAR)
Regeneration velocity [m/s] as a function of process air velocity, quadratic curve. curve = C1 + C2*v + C3*v**2 v = process air velocity [m/s]
Nominal Regeneration Temperature
Type: real number
Nominal regen temperature upon which the regen energy modifier curve is based. Not used if Default if chosen for the field Performance Mode Type. 121 C is a commonly used value.
Unit: C
Minimum: 40
Maximum: 250