class Standard
# @!group FanVariableVolume
include PrototypeFan
# Sets the fan pressure rise based on the Prototype buildings inputs
# which are governed by the flow rate coming through the fan
# and whether the fan lives inside a unit heater, PTAC, etc.
def fan_variable_volume_apply_prototype_fan_pressure_rise(fan_variable_volume)
# Get the max flow rate from the fan.
maximum_flow_rate_m3_per_s = nil
if fan_variable_volume.maximumFlowRate.is_initialized
maximum_flow_rate_m3_per_s = fan_variable_volume.maximumFlowRate.get
elsif fan_variable_volume.autosizedMaximumFlowRate.is_initialized
maximum_flow_rate_m3_per_s = fan_variable_volume.autosizedMaximumFlowRate.get
else
OpenStudio.logFree(OpenStudio::Warn, 'openstudio.prototype.FanVariableVolume', "For #{fan_variable_volume.name} max flow rate is not available, cannot apply prototype assumptions.")
return false
end
# Convert max flow rate to cfm
maximum_flow_rate_cfm = OpenStudio.convert(maximum_flow_rate_m3_per_s, 'm^3/s', 'cfm').get
# Pressure rise will be determined based on the
# following logic.
pressure_rise_in_h2o = 0.0
# If the fan lives inside of a zone hvac equipment
if fan_variable_volume.containingZoneHVACComponent.is_initialized
zone_hvac = fan_variable_volume.ZoneHVACComponent.get
if zone_hvac.to_ZoneHVACPackagedTerminalAirConditioner.is_initialized
pressure_rise_in_h2o = 1.33
elsif zone_hvac.to_ZoneHVACFourPipeFanCoil.is_initialized
pressure_rise_in_h2o = 1.33
elsif zone_hvac.to_ZoneHVACUnitHeater.is_initialized
pressure_rise_in_h2o = 0.2
else # This type of fan should not exist in the prototype models
return false
end
# If the fan lives on an airloop
elsif fan_variable_volume.airLoopHVAC.is_initialized
pressure_rise_in_h2o = fan_variable_volume_airloop_fan_pressure_rise(fan_variable_volume)
end
# Set the fan pressure rise
pressure_rise_pa = OpenStudio.convert(pressure_rise_in_h2o, 'inH_{2}O', 'Pa').get
fan_variable_volume.setPressureRise(pressure_rise_pa)
OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.FanVariableVolume', "For Prototype: #{fan_variable_volume.name}: #{maximum_flow_rate_cfm.round}cfm; Pressure Rise = #{pressure_rise_in_h2o}in w.c.")
return true
end
# Determine the prototype fan pressure rise for a variable volume
# fan on an AirLoopHVAC based on the airflow of the system.
# @return [Double] the pressure rise (in H2O). Defaults
# to the logic from ASHRAE 90.1-2004 prototypes.
def fan_variable_volume_airloop_fan_pressure_rise(fan_variable_volume)
# Get the max flow rate from the fan.
maximum_flow_rate_m3_per_s = nil
if fan_variable_volume.maximumFlowRate.is_initialized
maximum_flow_rate_m3_per_s = fan_variable_volume.maximumFlowRate.get
elsif fan_variable_volume.autosizedMaximumFlowRate.is_initialized
maximum_flow_rate_m3_per_s = fan_variable_volume.autosizedMaximumFlowRate.get
else
OpenStudio.logFree(OpenStudio::Warn, 'openstudio.prototype.FanVariableVolume', "For #{fan_variable_volume.name} max flow rate is not available, cannot apply prototype assumptions.")
return false
end
# Convert max flow rate to cfm
maximum_flow_rate_cfm = OpenStudio.convert(maximum_flow_rate_m3_per_s, 'm^3/s', 'cfm').get
# Determine the pressure rise
pressure_rise_in_h2o = if maximum_flow_rate_cfm < 4648
4.0
elsif maximum_flow_rate_cfm >= 4648 && maximum_flow_rate_cfm < 20_000
6.32
else # Over 20,000 cfm
5.58
end
return pressure_rise_in_h2o
end
def create_fan_variable_volume(model,
fan_name: nil,
fan_efficiency: nil,
pressure_rise: nil,
motor_efficiency: nil,
motor_in_airstream_fraction: nil,
fan_power_minimum_flow_rate_input_method: nil,
fan_power_minimum_flow_rate_fraction: nil,
fan_power_coefficient_1: nil,
fan_power_coefficient_2: nil,
fan_power_coefficient_3: nil,
fan_power_coefficient_4: nil,
fan_power_coefficient_5: nil,
end_use_subcategory: nil)
fan = OpenStudio::Model::FanVariableVolume.new(model)
PrototypeFan.apply_base_fan_variables(fan,
fan_name: fan_name,
fan_efficiency: fan_efficiency,
pressure_rise: pressure_rise,
end_use_subcategory: end_use_subcategory)
fan.setMotorEfficiency(motor_efficiency) unless motor_efficiency.nil?
fan.setMotorInAirstreamFraction(motor_in_airstream_fraction) unless motor_in_airstream_fraction.nil?
fan.setFanPowerMinimumFlowRateInputMethod(fan_power_minimum_flow_rate_input_method) unless fan_power_minimum_flow_rate_input_method.nil?
fan.setFanPowerMinimumFlowFraction(fan_power_minimum_flow_rate_fraction) unless fan_power_minimum_flow_rate_fraction.nil?
fan.setFanPowerCoefficient1(fan_power_coefficient_1) unless fan_power_coefficient_1.nil?
fan.setFanPowerCoefficient2(fan_power_coefficient_2) unless fan_power_coefficient_2.nil?
fan.setFanPowerCoefficient3(fan_power_coefficient_3) unless fan_power_coefficient_3.nil?
fan.setFanPowerCoefficient4(fan_power_coefficient_4) unless fan_power_coefficient_4.nil?
fan.setFanPowerCoefficient5(fan_power_coefficient_5) unless fan_power_coefficient_5.nil?
return fan
end
def create_fan_variable_volume_from_json(model,
fan_json,
fan_name: nil,
fan_efficiency: nil,
pressure_rise: nil,
motor_efficiency: nil,
motor_in_airstream_fraction: nil,
fan_power_minimum_flow_rate_input_method: nil,
fan_power_minimum_flow_rate_fraction: nil,
end_use_subcategory: nil,
fan_power_coefficient_1: nil,
fan_power_coefficient_2: nil,
fan_power_coefficient_3: nil,
fan_power_coefficient_4: nil,
fan_power_coefficient_5: nil)
# check values to use
fan_efficiency = fan_efficiency ? fan_efficiency : fan_json['fan_efficiency']
pressure_rise = pressure_rise ? pressure_rise : fan_json['pressure_rise']
motor_efficiency = motor_efficiency ? motor_efficiency : fan_json['motor_efficiency']
motor_in_airstream_fraction = motor_in_airstream_fraction ? motor_in_airstream_fraction : fan_json['motor_in_airstream_fraction']
fan_power_minimum_flow_rate_input_method = fan_power_minimum_flow_rate_input_method ? fan_power_minimum_flow_rate_input_method : fan_json['fan_power_minimum_flow_rate_input_method']
fan_power_minimum_flow_rate_fraction = fan_power_minimum_flow_rate_fraction ? fan_power_minimum_flow_rate_fraction : fan_json['fan_power_minimum_flow_rate_fraction']
fan_power_coefficient_1 = fan_power_coefficient_1 ? fan_power_coefficient_1 : fan_json['fan_power_coefficient_1']
fan_power_coefficient_2 = fan_power_coefficient_2 ? fan_power_coefficient_2 : fan_json['fan_power_coefficient_2']
fan_power_coefficient_3 = fan_power_coefficient_3 ? fan_power_coefficient_3 : fan_json['fan_power_coefficient_3']
fan_power_coefficient_4 = fan_power_coefficient_4 ? fan_power_coefficient_4 : fan_json['fan_power_coefficient_4']
fan_power_coefficient_5 = fan_power_coefficient_5 ? fan_power_coefficient_5 : fan_json['fan_power_coefficient_5']
# convert values
pressure_rise_pa = OpenStudio.convert(pressure_rise, 'inH_{2}O', 'Pa').get unless pressure_rise.nil?
# create fan
fan = create_fan_variable_volume(model,
fan_name:fan_name,
fan_efficiency: fan_efficiency,
pressure_rise: pressure_rise_pa,
motor_efficiency: motor_efficiency,
motor_in_airstream_fraction: motor_in_airstream_fraction,
fan_power_minimum_flow_rate_input_method: fan_power_minimum_flow_rate_input_method,
fan_power_minimum_flow_rate_fraction: fan_power_minimum_flow_rate_fraction,
end_use_subcategory: end_use_subcategory,
fan_power_coefficient_1: fan_power_coefficient_1,
fan_power_coefficient_2: fan_power_coefficient_2,
fan_power_coefficient_3: fan_power_coefficient_3,
fan_power_coefficient_4: fan_power_coefficient_4,
fan_power_coefficient_5: fan_power_coefficient_5)
return fan
end
end