Module: OpenstudioStandards::ThermalZone

Defined in:
lib/openstudio-standards/thermal_zone/thermal_zone.rb

Overview

The ThermalZone module provides methods get information about model thermal zones

Class Method Summary collapse

Class Method Details

.thermal_zone_add_unconditioned_thermostat(thermal_zone) ⇒ Boolean

Adds a thermostat that heats the space to 0 F and cools to 120 F. These numbers are outside of the threshold that is considered heated or cooled by thermal_zone_cooled?() and thermal_zone_heated?()

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if successful, false if not



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 476

def self.thermal_zone_add_unconditioned_thermostat(thermal_zone)
  # Heated to 0F (below thermal_zone_heated?(thermal_zone)  threshold)
  htg_t_f = 0
  htg_t_c = OpenStudio.convert(htg_t_f, 'F', 'C').get
  htg_stpt_sch = OpenStudio::Model::ScheduleRuleset.new(thermal_zone.model)
  htg_stpt_sch.setName('Unconditioned Minimal Heating')
  htg_stpt_sch.defaultDaySchedule.setName('Unconditioned Minimal Heating Default')
  htg_stpt_sch.defaultDaySchedule.addValue(OpenStudio::Time.new(0, 24, 0, 0), htg_t_c)

  # Cooled to 120F (above thermal_zone_cooled?(thermal_zone)  threshold)
  clg_t_f = 120
  clg_t_c = OpenStudio.convert(clg_t_f, 'F', 'C').get
  clg_stpt_sch = OpenStudio::Model::ScheduleRuleset.new(thermal_zone.model)
  clg_stpt_sch.setName('Unconditioned Minimal Heating')
  clg_stpt_sch.defaultDaySchedule.setName('Unconditioned Minimal Heating Default')
  clg_stpt_sch.defaultDaySchedule.addValue(OpenStudio::Time.new(0, 24, 0, 0), clg_t_c)

  # Thermostat
  thermostat = OpenStudio::Model::ThermostatSetpointDualSetpoint.new(thermal_zone.model)
  thermostat.setName("#{thermal_zone.name} Unconditioned Thermostat")
  thermostat.setHeatingSetpointTemperatureSchedule(htg_stpt_sch)
  thermostat.setCoolingSetpointTemperatureSchedule(clg_stpt_sch)
  thermal_zone.setThermostatSetpointDualSetpoint(thermostat)

  return true
end

.thermal_zone_convert_outdoor_air_to_per_area(thermal_zone) ⇒ Boolean

Convert total minimum OA requirement to a per-area value.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if successful, false if not



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 723

def self.thermal_zone_convert_outdoor_air_to_per_area(thermal_zone)
  # For each space in the zone, convert
  # all design OA to per-area
  # unless the "Outdoor Air Method" is "Maximum"
  thermal_zone.spaces.each do |space|
    # Find the design OA, which may be assigned at either the
    # SpaceType or directly at the Space
    dsn_oa = space.designSpecificationOutdoorAir
    next if dsn_oa.empty?

    dsn_oa = dsn_oa.get
    next if dsn_oa.outdoorAirMethod == 'Maximum'

    # Get the space properties
    floor_area = space.floorArea
    number_of_people = space.numberOfPeople
    volume = space.volume

    # Sum up the total OA from all sources
    oa_for_people = number_of_people * dsn_oa.outdoorAirFlowperPerson
    oa_for_floor_area = floor_area * dsn_oa.outdoorAirFlowperFloorArea
    oa_rate = dsn_oa.outdoorAirFlowRate
    oa_for_volume = volume * dsn_oa.outdoorAirFlowAirChangesperHour / 3600
    tot_oa = oa_for_people + oa_for_floor_area + oa_rate + oa_for_volume

    # Convert total to per-area
    tot_oa_per_area = tot_oa / floor_area

    # Check if there is another design OA object that has already
    # been converted from per-person to per-area that matches.
    # If so, reuse that instead of creating a duplicate.
    new_dsn_oa_name = "#{dsn_oa.name} to per-area"
    if thermal_zone.model.getDesignSpecificationOutdoorAirByName(new_dsn_oa_name).is_initialized
      new_dsn_oa = thermal_zone.model.getDesignSpecificationOutdoorAirByName(new_dsn_oa_name).get
    else
      new_dsn_oa = OpenStudio::Model::DesignSpecificationOutdoorAir.new(thermal_zone.model)
      new_dsn_oa.setName(new_dsn_oa_name)
    end

    # Assign this new design OA to the space
    space.setDesignSpecificationOutdoorAir(new_dsn_oa)

    # Set the method
    new_dsn_oa.setOutdoorAirMethod('Sum')
    # Set the per-area requirement
    new_dsn_oa.setOutdoorAirFlowperFloorArea(tot_oa_per_area)
    # Zero-out the per-person, ACH, and flow requirements
    new_dsn_oa.setOutdoorAirFlowperPerson(0.0)
    new_dsn_oa.setOutdoorAirFlowAirChangesperHour(0.0)
    new_dsn_oa.setOutdoorAirFlowRate(0.0)
    # Copy the orignal OA schedule, if any
    if dsn_oa.outdoorAirFlowRateFractionSchedule.is_initialized
      oa_sch = dsn_oa.outdoorAirFlowRateFractionSchedule.get
      new_dsn_oa.setOutdoorAirFlowRateFractionSchedule(oa_sch)
    end

    OpenStudio.logFree(OpenStudio::Info, 'openstudio.Standards.ThermalZone', "For #{thermal_zone.name}: Converted total ventilation requirements to per-area value.")
  end

  return true
end

.thermal_zone_cooled?(thermal_zone) ⇒ Boolean

Determines cooling status. If the zone has a thermostat with a minimum cooling setpoint below 33C (91F), counts as cooled. Plenums are also assumed to be cooled.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if cooled, false if not

Author:

  • Andrew Parker, Julien Marrec



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 243

def self.thermal_zone_cooled?(thermal_zone)
  temp_f = 91.0
  temp_c = OpenStudio.convert(temp_f, 'F', 'C').get
  cld = false

  # Consider plenum zones cooled
  area_plenum = 0
  area_non_plenum = 0
  thermal_zone.spaces.each do |space|
    if OpenstudioStandards::Space.space_plenum?(space)
      area_plenum += space.floorArea
    else
      area_non_plenum += space.floorArea
    end
  end

  # Majority
  if area_plenum > area_non_plenum
    cld = true
    return cld
  end

  # Check if the zone has radiant cooling,
  # and if it does, get cooling setpoint schedule
  # directly from the radiant system to check.
  thermal_zone.equipment.each do |equip|
    clg_sch = nil
    if equip.to_ZoneHVACLowTempRadiantConstFlow.is_initialized
      equip = equip.to_ZoneHVACLowTempRadiantConstFlow.get
      clg_coil = equip.coolingCoil
      if clg_coil.to_CoilCoolingLowTempRadiantConstFlow.is_initialized
        clg_coil = clg_coil.to_CoilCoolingLowTempRadiantConstFlow.get
        if clg_coil.coolingLowControlTemperatureSchedule.is_initialized
          clg_sch = clg_coil.coolingLowControlTemperatureSchedule.get
        end
      end
    elsif equip.to_ZoneHVACLowTempRadiantVarFlow.is_initialized
      equip = equip.to_ZoneHVACLowTempRadiantVarFlow.get
      clg_coil = equip.coolingCoil
      if equip.model.version > OpenStudio::VersionString.new('3.1.0')
        if clg_coil.is_initialized
          clg_coil = clg_coil.get
        else
          clg_coil = nil
        end
      end
      if !clg_coil.nil? && clg_coil.to_CoilCoolingLowTempRadiantVarFlow.is_initialized
        clg_coil = clg_coil.to_CoilCoolingLowTempRadiantVarFlow.get
        if clg_coil.coolingControlTemperatureSchedule.is_initialized
          clg_sch = clg_coil.coolingControlTemperatureSchedule.get
        end
      end
    end
    # Move on if no cooling schedule was found
    next if clg_sch.nil?

    # Get the setpoint from the schedule
    if clg_sch.to_ScheduleRuleset.is_initialized
      clg_sch = clg_sch.to_ScheduleRuleset.get
      min_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(clg_sch)['min']
      if min_c < temp_c
        cld = true
      end
    elsif clg_sch.to_ScheduleConstant.is_initialized
      clg_sch = clg_sch.to_ScheduleConstant.get
      min_c = OpenstudioStandards::Schedules.schedule_constant_get_min_max(clg_sch)['min']
      if min_c < temp_c
        cld = true
      end
    elsif clg_sch.to_ScheduleCompact.is_initialized
      clg_sch = clg_sch.to_ScheduleCompact.get
      min_c = OpenstudioStandards::Schedules.schedule_compact_get_min_max(clg_sch)['min']
      if min_c < temp_c
        cld = true
      end
    else
      OpenStudio.logFree(OpenStudio::Debug, 'OpenstudioStandards::ThermalZone', "Zone #{thermal_zone.name} used an unknown schedule type for the cooling setpoint; assuming cooled.")
      cld = true
    end
  end

  # Unheated if no thermostat present
  if thermal_zone.thermostat.empty?
    return cld
  end

  # Check the cooling setpoint
  tstat = thermal_zone.thermostat.get
  if tstat.to_ThermostatSetpointDualSetpoint
    tstat = tstat.to_ThermostatSetpointDualSetpoint.get
    clg_sch = tstat.getCoolingSchedule
    if clg_sch.is_initialized
      clg_sch = clg_sch.get
      if clg_sch.to_ScheduleRuleset.is_initialized
        clg_sch = clg_sch.to_ScheduleRuleset.get
        min_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(clg_sch)['min']
        if min_c < temp_c
          cld = true
        end
      elsif clg_sch.to_ScheduleConstant.is_initialized
        clg_sch = clg_sch.to_ScheduleConstant.get
        min_c = OpenstudioStandards::Schedules.schedule_constant_get_min_max(clg_sch)['min']
        if min_c < temp_c
          cld = true
        end
      elsif clg_sch.to_ScheduleCompact.is_initialized
        clg_sch = clg_sch.to_ScheduleCompact.get
        min_c = OpenstudioStandards::Schedules.schedule_compact_get_min_max(clg_sch)['min']
        if min_c < temp_c
          cld = true
        end
      else
        OpenStudio.logFree(OpenStudio::Debug, 'OpenstudioStandards::ThermalZone', "Zone #{thermal_zone.name} used an unknown schedule type for the cooling setpoint; assuming cooled.")
        cld = true
      end
    end
  elsif tstat.to_ZoneControlThermostatStagedDualSetpoint
    tstat = tstat.to_ZoneControlThermostatStagedDualSetpoint.get
    clg_sch = tstat.coolingTemperatureSetpointSchedule
    if clg_sch.is_initialized
      clg_sch = clg_sch.get
      if clg_sch.to_ScheduleRuleset.is_initialized
        clg_sch = clg_sch.to_ScheduleRuleset.get
        min_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(clg_sch)['min']
        if min_c < temp_c
          cld = true
        end
      end
    end
  elsif tstat.to_ThermostatSetpointSingleHeating
    cld = false
  end

  return cld
end

.thermal_zone_district_heat?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is heated by district or purchased heat. This will return true if there is any fossil heat, even if not the primary heating source. As an example, a zone served by a VRF + DOAS system will show as district heated if the DOAS ventilation air is heated by a district system

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    true if heated by district heat, false if electric or other.



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 438

def self.thermal_zone_district_heat?(thermal_zone)
  # error if HVACComponent heating fuels method is not available
  if thermal_zone.model.version < OpenStudio::VersionString.new('3.6.0')
    OpenStudio.logFree(OpenStudio::Error, 'OpenstudioStandards::ThermalZone', 'Required HVACComponent method .heatingFuelTypes is not available in pre-OpenStudio 3.6.0 versions. Use a more recent version of OpenStudio.')
  end

  is_district = false
  # Get an array of the heating fuels used by the zone
  htg_fuels = thermal_zone.heatingFuelTypes.map(&:valueName)
  if htg_fuels.include?('DistrictHeating') ||
     htg_fuels.include?('DistrictHeatingWater') ||
     htg_fuels.include?('DistrictHeatingSteam')

    is_district = true
  end

  return is_district
end

.thermal_zone_electric_heat?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is heated by electricity. This will return true if there is any electric heat, even if not the primary heating source.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    true if heated by electricity, false if fossil fuel or other.



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 384

def self.thermal_zone_electric_heat?(thermal_zone)
  # error if HVACComponent heating fuels method is not available
  if thermal_zone.model.version < OpenStudio::VersionString.new('3.6.0')
    OpenStudio.logFree(OpenStudio::Error, 'OpenstudioStandards::ThermalZone', 'Required HVACComponent method .heatingFuelTypes is not available in pre-OpenStudio 3.6.0 versions. Use a more recent version of OpenStudio.')
  end

  # Get an array of the heating fuels used by the zone
  htg_fuels = thermal_zone.heatingFuelTypes.map(&:valueName)
  is_electric = htg_fuels.include?('Electricity')

  return is_electric
end

.thermal_zone_fossil_heat?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is heated by a fossil fuel. This will return true if there is any fossil heat, even if not the primary heating source. As an example, a zone served by a VRF + DOAS system will show as fossil heated if the DOAS ventilation air is fossil heated

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    true if heated by fossil fuel, false if electric or other.



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 404

def self.thermal_zone_fossil_heat?(thermal_zone)
  # error if HVACComponent heating fuels method is not available
  if thermal_zone.model.version < OpenStudio::VersionString.new('3.6.0')
    OpenStudio.logFree(OpenStudio::Error, 'OpenstudioStandards::ThermalZone', 'Required HVACComponent method .heatingFuelTypes is not available in pre-OpenStudio 3.6.0 versions. Use a more recent version of OpenStudio.')
  end

  is_fossil = false
  # Get an array of the heating fuels used by the zone
  htg_fuels = thermal_zone.heatingFuelTypes.map(&:valueName)
  if htg_fuels.include?('Gas') ||
     htg_fuels.include?('NaturalGas') ||
     htg_fuels.include?('Propane') ||
     htg_fuels.include?('PropaneGas') ||
     htg_fuels.include?('FuelOil_1') ||
     htg_fuels.include?('FuelOilNo1') ||
     htg_fuels.include?('FuelOil_2') ||
     htg_fuels.include?('FuelOilNo2') ||
     htg_fuels.include?('Coal') ||
     htg_fuels.include?('Diesel') ||
     htg_fuels.include?('Gasoline')

    is_fossil = true
  end

  return is_fossil
end

.thermal_zone_get_building_type(thermal_zone) ⇒ String

Returns the standards building type that represents the majority of floor area.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (String) —

    the standards building type



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 548

def self.thermal_zone_get_building_type(thermal_zone)
  # determine areas of each building type
  building_type_areas = {}
  thermal_zone.spaces.each do |space|
    # ignore space if not part of total area
    next unless space.partofTotalFloorArea

    if space.spaceType.is_initialized
      space_type = space.spaceType.get
      if space_type.standardsBuildingType.is_initialized
        building_type = space_type.standardsBuildingType.get
        if building_type_areas[building_type].nil?
          building_type_areas[building_type] = space.floorArea
        else
          building_type_areas[building_type] += space.floorArea
        end
      end
    end
  end

  # return largest building type area
  building_type = building_type_areas.key(building_type_areas.values.max)

  if building_type.nil?
    OpenStudio.logFree(OpenStudio::Info, 'OpenstudioStandards::ThermalZone', "Thermal zone #{thermal_zone.name} does not have standards building type.")
  end

  return building_type
end

.thermal_zone_get_design_internal_load(thermal_zone) ⇒ Double

Determine the design internal load (W) for this zone without space multipliers. This include People, Lights, Electric Equipment, and Gas Equipment in all spaces in this zone. It assumes 100% of the wattage is converted to heat, and that the design peak schedule value is 1 (100%).

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Double) —

    the design internal load, in watts



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 509

def self.thermal_zone_get_design_internal_load(thermal_zone)
  load_w = 0.0

  thermal_zone.spaces.each do |space|
    load_w += OpenstudioStandards::Space.space_get_design_internal_load(space)
  end

  return load_w
end

.thermal_zone_get_occupancy_schedule(thermal_zone, sch_name: nil, occupied_percentage_threshold: nil) ⇒ <OpenStudio::Model::ScheduleRuleset>

This method creates a new fractional schedule ruleset. If occupied_percentage_threshold is set, this method will return a discrete on/off fractional schedule with a value of one when occupancy across all spaces is greater than or equal to the occupied_percentage_threshold, and zero all other times. Otherwise the method will return the weighted fractional occupancy schedule.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

  • sch_name (String) (defaults to: nil) —

    the name of the generated occupancy schedule

  • occupied_percentage_threshold (Double) (defaults to: nil) —

    the minimum fraction (0 to 1) that counts as occupied if this parameter is set, the returned ScheduleRuleset will be 0 = unoccupied, 1 = occupied otherwise the ScheduleRuleset will be the weighted fractional occupancy schedule

Returns:

  • (<OpenStudio::Model::ScheduleRuleset>) —

    OpenStudio ScheduleRuleset of fractional or discrete occupancy



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 589

def self.thermal_zone_get_occupancy_schedule(thermal_zone, sch_name: nil, occupied_percentage_threshold: nil)
  if sch_name.nil?
    sch_name = "#{thermal_zone.name} Occ Sch"
  end
  # Get the occupancy schedule for all spaces in thermal_zone
  sch_ruleset = OpenstudioStandards::Space.spaces_get_occupancy_schedule(thermal_zone.spaces,
                                                                         sch_name: sch_name,
                                                                         occupied_percentage_threshold: occupied_percentage_threshold)
  return sch_ruleset
end

.thermal_zone_get_outdoor_airflow_rate(thermal_zone) ⇒ Double

Calculates the zone outdoor airflow requirement (Voz) based on the inputs in the DesignSpecification:OutdoorAir objects in all spaces in the zone.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Double) —

    the zone outdoor air flow rate in cubic meters per second (m^3/s)



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 633

def self.thermal_zone_get_outdoor_airflow_rate(thermal_zone)
  tot_oa_flow_rate = 0.0

  spaces = thermal_zone.spaces.sort

  sum_floor_area = 0.0
  sum_number_of_people = 0.0
  sum_volume = 0.0

  # Variables for merging outdoor air
  any_max_oa_method = false
  sum_oa_for_people = 0.0
  sum_oa_for_floor_area = 0.0
  sum_oa_rate = 0.0
  sum_oa_for_volume = 0.0

  # Find common variables for the new space
  spaces.each do |space|
    floor_area = space.floorArea
    sum_floor_area += floor_area

    number_of_people = space.numberOfPeople
    sum_number_of_people += number_of_people

    volume = space.volume
    sum_volume += volume

    dsn_oa = space.designSpecificationOutdoorAir
    next if dsn_oa.empty?

    dsn_oa = dsn_oa.get

    # compute outdoor air rates in case we need them
    oa_for_people = number_of_people * dsn_oa.outdoorAirFlowperPerson
    oa_for_floor_area = floor_area * dsn_oa.outdoorAirFlowperFloorArea
    oa_rate = dsn_oa.outdoorAirFlowRate
    oa_for_volume = volume * dsn_oa.outdoorAirFlowAirChangesperHour / 3600

    # First check if this space uses the Maximum method and other spaces do not
    if dsn_oa.outdoorAirMethod == 'Maximum'
      sum_oa_rate += [oa_for_people, oa_for_floor_area, oa_rate, oa_for_volume].max
    elsif dsn_oa.outdoorAirMethod == 'Sum'
      sum_oa_for_people += oa_for_people
      sum_oa_for_floor_area += oa_for_floor_area
      sum_oa_rate += oa_rate
      sum_oa_for_volume += oa_for_volume
    end
  end

  tot_oa_flow_rate += sum_oa_for_people
  tot_oa_flow_rate += sum_oa_for_floor_area
  tot_oa_flow_rate += sum_oa_rate
  tot_oa_flow_rate += sum_oa_for_volume

  # Convert to cfm
  tot_oa_flow_rate_cfm = OpenStudio.convert(tot_oa_flow_rate, 'm^3/s', 'cfm').get

  OpenStudio.logFree(OpenStudio::Debug, 'openstudio.Standards.ThermalZone', "For #{thermal_zone.name}, design min OA = #{tot_oa_flow_rate_cfm.round} cfm.")

  return tot_oa_flow_rate
end

.thermal_zone_get_outdoor_airflow_rate_per_area(thermal_zone) ⇒ Double

Calculates the zone outdoor airflow requirement and divides by the zone area.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Double) —

    the zone outdoor air flow rate per area in cubic meters per second (m^3/s)



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 699

def self.thermal_zone_get_outdoor_airflow_rate_per_area(thermal_zone)
  tot_oa_flow_rate_per_area = 0.0

  # Find total area of the zone
  sum_floor_area = 0.0
  thermal_zone.spaces.sort.each do |space|
    sum_floor_area += space.floorArea
  end

  # Get the OA flow rate
  tot_oa_flow_rate = OpenstudioStandards::ThermalZone.thermal_zone_get_outdoor_airflow_rate(thermal_zone)

  # Calculate the per-area value
  tot_oa_flow_rate_per_area = tot_oa_flow_rate / sum_floor_area

  # OpenStudio::logFree(OpenStudio::Debug, "openstudio.Standards.Model", "For #{self.name}, OA per area = #{tot_oa_flow_rate_per_area.round(8)} m^3/s*m^2.")

  return tot_oa_flow_rate_per_area
end

.thermal_zone_get_space_type(thermal_zone) ⇒ Boost::Optional<OpenStudio::Model::SpaceType>

Returns the space type that represents a majority of the floor area.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boost::Optional<OpenStudio::Model::SpaceType>) —

    An OptionalSpaceType



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 523

def self.thermal_zone_get_space_type(thermal_zone)
  space_type_to_area = Hash.new(0.0)

  thermal_zone.spaces.each do |space|
    if space.spaceType.is_initialized
      space_type = space.spaceType.get
      space_type_to_area[space_type] += space.floorArea
    end
  end

  # If no space types, return empty optional SpaceType
  if space_type_to_area.empty?
    return OpenStudio::Model::OptionalSpaceType.new
  end

  # Sort by area
  biggest_space_type = space_type_to_area.sort_by { |st, area| area }.reverse[0][0]

  return OpenStudio::Model::OptionalSpaceType.new(biggest_space_type)
end

.thermal_zone_heated?(thermal_zone) ⇒ Boolean

Determines heating status. If the zone has a thermostat with a maximum heating setpoint above 5C (41F), counts as heated. Plenums are also assumed to be heated.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if heated, false if not

Author:

  • Andrew Parker, Julien Marrec



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 94

def self.thermal_zone_heated?(thermal_zone)
  temp_f = 41.0
  temp_c = OpenStudio.convert(temp_f, 'F', 'C').get
  htd = false

  # Consider plenum zones heated
  area_plenum = 0
  area_non_plenum = 0
  thermal_zone.spaces.each do |space|
    if OpenstudioStandards::Space.space_plenum?(space)
      area_plenum += space.floorArea
    else
      area_non_plenum += space.floorArea
    end
  end

  # Majority
  if area_plenum > area_non_plenum
    htd = true
    return htd
  end

  # Check if the zone has radiant heating,
  # and if it does, get heating setpoint schedule
  # directly from the radiant system to check.
  thermal_zone.equipment.each do |equip|
    htg_sch = nil
    if equip.to_ZoneHVACHighTemperatureRadiant.is_initialized
      equip = equip.to_ZoneHVACHighTemperatureRadiant.get
      if equip.heatingSetpointTemperatureSchedule.is_initialized
        htg_sch = equip.heatingSetpointTemperatureSchedule.get
      end
    elsif equip.to_ZoneHVACLowTemperatureRadiantElectric.is_initialized
      equip = equip.to_ZoneHVACLowTemperatureRadiantElectric.get
      htg_sch = equip.heatingSetpointTemperatureSchedule
    elsif equip.to_ZoneHVACLowTempRadiantConstFlow.is_initialized
      equip = equip.to_ZoneHVACLowTempRadiantConstFlow.get
      htg_coil = equip.heatingCoil
      if htg_coil.to_CoilHeatingLowTempRadiantConstFlow.is_initialized
        htg_coil = htg_coil.to_CoilHeatingLowTempRadiantConstFlow.get
        if htg_coil.heatingHighControlTemperatureSchedule.is_initialized
          htg_sch = htg_coil.heatingHighControlTemperatureSchedule.get
        end
      end
    elsif equip.to_ZoneHVACLowTempRadiantVarFlow.is_initialized
      equip = equip.to_ZoneHVACLowTempRadiantVarFlow.get
      htg_coil = equip.heatingCoil
      if equip.model.version > OpenStudio::VersionString.new('3.1.0')
        if htg_coil.is_initialized
          htg_coil = htg_coil.get
        else
          htg_coil = nil
        end
      end
      if !htg_coil.nil? && htg_coil.to_CoilHeatingLowTempRadiantVarFlow.is_initialized
        htg_coil = htg_coil.to_CoilHeatingLowTempRadiantVarFlow.get
        if htg_coil.heatingControlTemperatureSchedule.is_initialized
          htg_sch = htg_coil.heatingControlTemperatureSchedule.get
        end
      end
    end
    # Move on if no heating schedule was found
    next if htg_sch.nil?

    # Get the setpoint from the schedule
    if htg_sch.to_ScheduleRuleset.is_initialized
      htg_sch = htg_sch.to_ScheduleRuleset.get
      max_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(htg_sch)['max']
      if max_c > temp_c
        htd = true
      end
    elsif htg_sch.to_ScheduleConstant.is_initialized
      htg_sch = htg_sch.to_ScheduleConstant.get
      max_c = OpenstudioStandards::Schedules.schedule_constant_get_min_max(htg_sch)['max']
      if max_c > temp_c
        htd = true
      end
    elsif htg_sch.to_ScheduleCompact.is_initialized
      htg_sch = htg_sch.to_ScheduleCompact.get
      max_c = OpenstudioStandards::Schedules.schedule_compact_get_min_max(htg_sch)['max']
      if max_c > temp_c
        htd = true
      end
    else
      OpenStudio.logFree(OpenStudio::Debug, 'OpenstudioStandards::ThermalZone', "Zone #{thermal_zone.name} used an unknown schedule type for the heating setpoint; assuming heated.")
      htd = true
    end
  end

  # Unheated if no thermostat present
  if thermal_zone.thermostat.empty?
    return htd
  end

  # Check the heating setpoint
  tstat = thermal_zone.thermostat.get
  if tstat.to_ThermostatSetpointDualSetpoint
    tstat = tstat.to_ThermostatSetpointDualSetpoint.get
    htg_sch = tstat.getHeatingSchedule
    if htg_sch.is_initialized
      htg_sch = htg_sch.get
      if htg_sch.to_ScheduleRuleset.is_initialized
        htg_sch = htg_sch.to_ScheduleRuleset.get
        max_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(htg_sch)['max']
        if max_c > temp_c
          htd = true
        end
      elsif htg_sch.to_ScheduleConstant.is_initialized
        htg_sch = htg_sch.to_ScheduleConstant.get
        max_c = OpenstudioStandards::Schedules.schedule_constant_get_min_max(htg_sch)['max']
        if max_c > temp_c
          htd = true
        end
      elsif htg_sch.to_ScheduleCompact.is_initialized
        htg_sch = htg_sch.to_ScheduleCompact.get
        max_c = OpenstudioStandards::Schedules.schedule_compact_get_min_max(htg_sch)['max']
        if max_c > temp_c
          htd = true
        end
      else
        OpenStudio.logFree(OpenStudio::Debug, 'OpenstudioStandards::ThermalZone', "Zone #{thermal_zone.name} used an unknown schedule type for the heating setpoint; assuming heated.")
        htd = true
      end
    end
  elsif tstat.to_ZoneControlThermostatStagedDualSetpoint
    tstat = tstat.to_ZoneControlThermostatStagedDualSetpoint.get
    htg_sch = tstat.heatingTemperatureSetpointSchedule
    if htg_sch.is_initialized
      htg_sch = htg_sch.get
      if htg_sch.to_ScheduleRuleset.is_initialized
        htg_sch = htg_sch.to_ScheduleRuleset.get
        max_c = OpenstudioStandards::Schedules.schedule_ruleset_get_min_max(htg_sch)['max']
        if max_c > temp_c
          htd = true
        end
      end
    end
  end

  return htd
end

.thermal_zone_mixed_heat?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is heated by two or more of electricity, fossil fuel, and district or purchased heat.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    true if mixed fossil, electric, and district/purchased heat, false if not



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 461

def self.thermal_zone_mixed_heat?(thermal_zone)
  electric_heat = OpenstudioStandards::ThermalZone.thermal_zone_electric_heat?(thermal_zone)
  fossil_heat = OpenstudioStandards::ThermalZone.thermal_zone_fossil_heat?(thermal_zone)
  district_heat = OpenstudioStandards::ThermalZone.thermal_zone_district_heat?(thermal_zone)
  is_mixed = [electric_heat, fossil_heat, district_heat].count(true) > 1

  return is_mixed
end

.thermal_zone_plenum?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is a plenum based on whether a majority of the spaces in the zone are plenums or not.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if majority plenum, false if not



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 8

def self.thermal_zone_plenum?(thermal_zone)
  plenum_status = false

  area_plenum = 0
  area_non_plenum = 0
  thermal_zone.spaces.each do |space|
    if OpenstudioStandards::Space.space_plenum?(space)
      area_plenum += space.floorArea
    else
      area_non_plenum += space.floorArea
    end
  end

  # Majority
  if area_plenum > area_non_plenum
    plenum_status = true
  end

  return plenum_status
end

.thermal_zone_residential?(thermal_zone) ⇒ Boolean

Determine if the thermal zone is residential based on the space type properties for the spaces in the zone. If there are both residential and nonresidential spaces in the zone, the result will be whichever type has more floor area. In the event that they are equal, it will be assumed nonresidential.

return [Boolean] true if residential, false if nonresidential

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) 


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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 36

def self.thermal_zone_residential?(thermal_zone)
  # Determine the respective areas
  res_area_m2 = 0
  nonres_area_m2 = 0
  thermal_zone.spaces.each do |space|
    # Ignore space if not part of total area
    next unless space.partofTotalFloorArea

    if OpenstudioStandards::Space.space_residential?(space)
      res_area_m2 += space.floorArea
    else
      nonres_area_m2 += space.floorArea
    end
  end

  # Determine which is larger
  is_res = false
  if res_area_m2 > nonres_area_m2
    is_res = true
  end

  return is_res
end

.thermal_zone_vestibule?(thermal_zone) ⇒ Boolean

Determine if this zone is a vestibule. Zone must be less than 200 ft^2 and also have an infiltration object specified using Flow/Zone.

Parameters:

  • thermal_zone (OpenStudio::Model::ThermalZone) —

    OpenStudio ThermalZone object

Returns:

  • (Boolean) —

    returns true if vestibule, false if not



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 65

def self.thermal_zone_vestibule?(thermal_zone)
  is_vest = false

  # Check area
  unless thermal_zone.floorArea < OpenStudio.convert(200, 'ft^2', 'm^2').get
    return is_vest
  end

  # Check presence of infiltration
  thermal_zone.spaces.each do |space|
    space.spaceInfiltrationDesignFlowRates.each do |infil|
      if infil.designFlowRate.is_initialized
        is_vest = true
        OpenStudio.logFree(OpenStudio::Info, 'OpenstudioStandards::ThermalZone', "For #{thermal_zone.name}: This zone is considered a vestibule.")
        break
      end
    end
  end

  return is_vest
end

.thermal_zones_get_occupancy_schedule(thermal_zones, sch_name: nil, occupied_percentage_threshold: nil) ⇒ <OpenStudio::Model::ScheduleRuleset>

This method creates a new fractional schedule ruleset. If occupied_percentage_threshold is set, this method will return a discrete on/off fractional schedule with a value of one when occupancy across all spaces is greater than or equal to the occupied_percentage_threshold, and zero all other times. Otherwise the method will return the weighted fractional occupancy schedule.

Parameters:

  • thermal_zones (Array<OpenStudio::Model::ThermalZone>) —

    Array of OpenStudio ThermalZone objects

  • sch_name (String) (defaults to: nil) —

    the name of the generated occupancy schedule

  • occupied_percentage_threshold (Double) (defaults to: nil) —

    the minimum fraction (0 to 1) that counts as occupied if this parameter is set, the returned ScheduleRuleset will be 0 = unoccupied, 1 = occupied otherwise the ScheduleRuleset will be the weighted fractional occupancy schedule

Returns:

  • (<OpenStudio::Model::ScheduleRuleset>) —

    OpenStudio ScheduleRuleset of fractional or discrete occupancy



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# File 'lib/openstudio-standards/thermal_zone/thermal_zone.rb', line 611

def self.thermal_zones_get_occupancy_schedule(thermal_zones, sch_name: nil, occupied_percentage_threshold: nil)
  if sch_name.nil?
    sch_name = "#{thermal_zones.size} zone Occ Sch"
  end
  # Get the occupancy schedule for all spaces in thermal_zones
  spaces = []
  thermal_zones.each do |thermal_zone|
    thermal_zone.spaces.each do |space|
      spaces << space
    end
  end
  sch_ruleset = OpenstudioStandards::Space.spaces_get_occupancy_schedule(spaces,
                                                                         sch_name: sch_name,
                                                                         occupied_percentage_threshold: occupied_percentage_threshold)
  return sch_ruleset
end