Class: ASHRAE9012010

Inherits:
ASHRAE901 show all
Includes:
ASHRAE9012010CoolingTower
Defined in:
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.ThermalZone.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanVariableVolume.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.CoolingTowerTwoSpeed.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.CoolingTowerSingleSpeed.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.CoolingTowerVariableSpeed.rb,
lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanOnOff.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.elevators.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanConstantVolume.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanVariableVolume.rb,
lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb

Overview

This class holds methods that apply ASHRAE 90.1-2010 to a given model.

Technical References:

Constant Summary collapse

@@template =

rubocop:disable Style/ClassVars

'90.1-2010'

Instance Attribute Summary collapse

Model collapse

Space collapse

AirLoopHVAC collapse

ThermalZone collapse

FanVariableVolume collapse

AirTerminalSingleDuctVAVReheat collapse

FanOnOff collapse

elevators collapse

FanConstantVolume collapse

CoolingTower collapse

Instance Method Summary collapse

Constructor Details

#initializeASHRAE9012010


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.rb', line 9

def initialize
  super()
  @template = @@template
  load_standards_database
end

Instance Attribute Details

#templateObject (readonly)

Returns the value of attribute template


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.rb', line 7

def template
  @template
end

Instance Method Details

#air_loop_hvac_apply_multizone_vav_outdoor_air_sizing(air_loop_hvac) ⇒ Object

TODO:

move building-type-specific code to Prototype classes

Apply multizone vav outdoor air method and adjust multizone VAV damper positions to achieve a system minimum ventilation effectiveness of 0.6 per PNNL. Hard-size the resulting min OA into the sizing:system object.

return [Bool] returns true if successful, false if not


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 12

def air_loop_hvac_apply_multizone_vav_outdoor_air_sizing(air_loop_hvac)
  # First time adjustment:
  # Only applies to multi-zone vav systems
  # exclusion: for Outpatient: (1) both AHU1 and AHU2 in 'DOE Ref Pre-1980' and 'DOE Ref 1980-2004'
  # (2) AHU1 in 2004-2013
  # TODO refactor: move building-type-specific code to Prototype classes
  if air_loop_hvac_multizone_vav_system?(air_loop_hvac) && !(air_loop_hvac.name.to_s.include? 'Outpatient F1')
    air_loop_hvac_adjust_minimum_vav_damper_positions(air_loop_hvac)
  end

  # Second time adjustment:
  # Only apply to 2010 and 2013 Outpatient (both AHU1 and AHU2)
  # TODO maybe apply to hospital as well?
  # TODO refactor: move building-type-specific code to Prototype classes
  if air_loop_hvac.name.to_s.include? 'Outpatient'
    air_loop_hvac_adjust_minimum_vav_damper_positions_outpatient(air_loop_hvac)
  end

  return true
end

#air_loop_hvac_demand_control_ventilation_limits(air_loop_hvac) ⇒ Array<Double>

Determines the OA flow rates above which an economizer is required. Two separate rates, one for systems with an economizer and another for systems without. are zero for both types.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 252

def air_loop_hvac_demand_control_ventilation_limits(air_loop_hvac)
  min_oa_without_economizer_cfm = 3000
  min_oa_with_economizer_cfm = 1200
  return [min_oa_without_economizer_cfm, min_oa_with_economizer_cfm]
end

#air_loop_hvac_economizer_limits(air_loop_hvac, climate_zone) ⇒ Array<Double>

Determine the limits for the type of economizer present on the AirLoopHVAC, if any.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 36

def air_loop_hvac_economizer_limits(air_loop_hvac, climate_zone)
  drybulb_limit_f = nil
  enthalpy_limit_btu_per_lb = nil
  dewpoint_limit_f = nil

  # Get the OA system and OA controller
  oa_sys = air_loop_hvac.airLoopHVACOutdoorAirSystem
  if oa_sys.is_initialized
    oa_sys = oa_sys.get
  else
    return [nil, nil, nil] # No OA system
  end
  oa_control = oa_sys.getControllerOutdoorAir
  economizer_type = oa_control.getEconomizerControlType

  case economizer_type
  when 'NoEconomizer'
    return [nil, nil, nil]
  when 'FixedDryBulb'
    case climate_zone
    when 'ASHRAE 169-2006-1B',
        'ASHRAE 169-2006-2B',
        'ASHRAE 169-2006-3B',
        'ASHRAE 169-2006-3C',
        'ASHRAE 169-2006-4B',
        'ASHRAE 169-2006-4C',
        'ASHRAE 169-2006-5B',
        'ASHRAE 169-2006-5C',
        'ASHRAE 169-2006-6B',
        'ASHRAE 169-2006-7A',
        'ASHRAE 169-2006-7B',
        'ASHRAE 169-2006-8A',
        'ASHRAE 169-2006-8B'
      drybulb_limit_f = 75
    when 'ASHRAE 169-2006-5A',
        'ASHRAE 169-2006-6A'
      drybulb_limit_f = 70
    end
  when 'FixedEnthalpy'
    enthalpy_limit_btu_per_lb = 28
  when 'FixedDewPointAndDryBulb'
    drybulb_limit_f = 75
    dewpoint_limit_f = 55
  end

  return [drybulb_limit_f, enthalpy_limit_btu_per_lb, dewpoint_limit_f]
end

#air_loop_hvac_economizer_type_allowable?(air_loop_hvac, climate_zone) ⇒ Bool

Check the economizer type currently specified in the ControllerOutdoorAir object on this air loop is acceptable per the standard.

Returns false if the economizer type is not allowable.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 97

def air_loop_hvac_economizer_type_allowable?(air_loop_hvac, climate_zone)
  # EnergyPlus economizer types
  # 'NoEconomizer'
  # 'FixedDryBulb'
  # 'FixedEnthalpy'
  # 'DifferentialDryBulb'
  # 'DifferentialEnthalpy'
  # 'FixedDewPointAndDryBulb'
  # 'ElectronicEnthalpy'
  # 'DifferentialDryBulbAndEnthalpy'

  # Get the OA system and OA controller
  oa_sys = air_loop_hvac.airLoopHVACOutdoorAirSystem
  if oa_sys.is_initialized
    oa_sys = oa_sys.get
  else
    return true # No OA system
  end
  oa_control = oa_sys.getControllerOutdoorAir
  economizer_type = oa_control.getEconomizerControlType

  # Return true if no economizer is present
  if economizer_type == 'NoEconomizer'
    return true
  end

  # Determine the prohibited types
  prohibited_types = []
  case climate_zone
  when 'ASHRAE 169-2006-1B',
      'ASHRAE 169-2006-2B',
      'ASHRAE 169-2006-3B',
      'ASHRAE 169-2006-3C',
      'ASHRAE 169-2006-4B',
      'ASHRAE 169-2006-4C',
      'ASHRAE 169-2006-5B',
      'ASHRAE 169-2006-6B',
      'ASHRAE 169-2006-7A',
      'ASHRAE 169-2006-7B',
      'ASHRAE 169-2006-8A',
      'ASHRAE 169-2006-8B'
    prohibited_types = ['FixedEnthalpy']
  when
    'ASHRAE 169-2006-1A',
      'ASHRAE 169-2006-2A',
      'ASHRAE 169-2006-3A',
      'ASHRAE 169-2006-4A'
    prohibited_types = ['FixedDryBulb', 'DifferentialDryBulb']
  when
    'ASHRAE 169-2006-5A',
      'ASHRAE 169-2006-6A',
      prohibited_types = []
  end

  # Check if the specified type is allowed
  economizer_type_allowed = true
  if prohibited_types.include?(economizer_type)
    economizer_type_allowed = false
  end

  return economizer_type_allowed
end

#air_loop_hvac_energy_recovery_ventilator_flow_limit(air_loop_hvac, climate_zone, pct_oa) ⇒ Double

Determine the airflow limits that govern whether or not an ERV is required. Based on climate zone and % OA. if nil, ERV is never required.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 344

def air_loop_hvac_energy_recovery_ventilator_flow_limit(air_loop_hvac, climate_zone, pct_oa)
  # Table 6.5.6.1
  case climate_zone
  when 'ASHRAE 169-2006-3B', 'ASHRAE 169-2006-3C', 'ASHRAE 169-2006-4B', 'ASHRAE 169-2006-4C', 'ASHRAE 169-2006-5B'
    if pct_oa < 0.3
      erv_cfm = nil
    elsif pct_oa >= 0.3 && pct_oa < 0.4
      erv_cfm = nil
    elsif pct_oa >= 0.4 && pct_oa < 0.5
      erv_cfm = nil
    elsif pct_oa >= 0.5 && pct_oa < 0.6
      erv_cfm = nil
    elsif pct_oa >= 0.6 && pct_oa < 0.7
      erv_cfm = nil
    elsif pct_oa >= 0.7 && pct_oa < 0.8
      erv_cfm = 5000
    elsif pct_oa >= 0.8
      erv_cfm = 5000
    end
  when 'ASHRAE 169-2006-1B', 'ASHRAE 169-2006-2B', 'ASHRAE 169-2006-5C'
    if pct_oa < 0.3
      erv_cfm = nil
    elsif pct_oa >= 0.3 && pct_oa < 0.4
      erv_cfm = nil
    elsif pct_oa >= 0.4 && pct_oa < 0.5
      erv_cfm = nil
    elsif pct_oa >= 0.5 && pct_oa < 0.6
      erv_cfm = 26_000
    elsif pct_oa >= 0.6 && pct_oa < 0.7
      erv_cfm = 12_000
    elsif pct_oa >= 0.7 && pct_oa < 0.8
      erv_cfm = 5000
    elsif pct_oa >= 0.8
      erv_cfm = 4000
    end
  when 'ASHRAE 169-2006-6B'
    if pct_oa < 0.3
      erv_cfm = nil
    elsif pct_oa >= 0.3 && pct_oa < 0.4
      erv_cfm = 11_000
    elsif pct_oa >= 0.4 && pct_oa < 0.5
      erv_cfm = 5500
    elsif pct_oa >= 0.5 && pct_oa < 0.6
      erv_cfm = 4500
    elsif pct_oa >= 0.6 && pct_oa < 0.7
      erv_cfm = 3500
    elsif pct_oa >= 0.7 && pct_oa < 0.8
      erv_cfm = 2500
    elsif pct_oa >= 0.8
      erv_cfm = 1500
    end
  when 'ASHRAE 169-2006-1A', 'ASHRAE 169-2006-2A', 'ASHRAE 169-2006-3A', 'ASHRAE 169-2006-4A', 'ASHRAE 169-2006-5A', 'ASHRAE 169-2006-6A'
    if pct_oa < 0.3
      erv_cfm = nil
    elsif pct_oa >= 0.3 && pct_oa < 0.4
      erv_cfm = 5500
    elsif pct_oa >= 0.4 && pct_oa < 0.5
      erv_cfm = 4500
    elsif pct_oa >= 0.5 && pct_oa < 0.6
      erv_cfm = 3500
    elsif pct_oa >= 0.6 && pct_oa < 0.7
      erv_cfm = 2000
    elsif pct_oa >= 0.7 && pct_oa < 0.8
      erv_cfm = 1000
    elsif pct_oa >= 0.8
      erv_cfm = 0
    end
  when 'ASHRAE 169-2006-7A', 'ASHRAE 169-2006-7B', 'ASHRAE 169-2006-8A', 'ASHRAE 169-2006-8B'
    if pct_oa < 0.3
      erv_cfm = nil
    elsif pct_oa >= 0.3 && pct_oa < 0.4
      erv_cfm = 2500
    elsif pct_oa >= 0.4 && pct_oa < 0.5
      erv_cfm = 1000
    elsif pct_oa >= 0.5 && pct_oa < 0.6
      erv_cfm = 0
    elsif pct_oa >= 0.6 && pct_oa < 0.7
      erv_cfm = 0
    elsif pct_oa >= 0.7 && pct_oa < 0.8
      erv_cfm = 0
    elsif pct_oa >= 0.8
      erv_cfm = 0
    end
  end

  return erv_cfm
end

#air_loop_hvac_integrated_economizer_required?(air_loop_hvac, climate_zone) ⇒ Boolean

Determine if the system economizer must be integrated or not. All economizers must be integrated in 90.1-2010


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 86

def air_loop_hvac_integrated_economizer_required?(air_loop_hvac, climate_zone)
  integrated_economizer_required = true
  return integrated_economizer_required
end

#air_loop_hvac_motorized_oa_damper_limits(air_loop_hvac, climate_zone) ⇒ Array<Double>

Determine the air flow and number of story limits for whether motorized OA damper is required.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 261

def air_loop_hvac_motorized_oa_damper_limits(air_loop_hvac, climate_zone)
  case climate_zone
  when 'ASHRAE 169-2006-1A',
      'ASHRAE 169-2006-1B',
      'ASHRAE 169-2006-2A',
      'ASHRAE 169-2006-2B',
      'ASHRAE 169-2006-3A',
      'ASHRAE 169-2006-3B',
      'ASHRAE 169-2006-3C',
    minimum_oa_flow_cfm = 300
    maximum_stories = 999 # Any number of stories
  else
    minimum_oa_flow_cfm = 300
    maximum_stories = 0
  end

  return [minimum_oa_flow_cfm, maximum_stories]
end

#air_loop_hvac_multizone_vav_optimization_required?(air_loop_hvac, climate_zone) ⇒ Bool

TODO:

Add exception logic for systems with AIA healthcare ventilation requirements dual duct systems

Determine if multizone vav optimization is required.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 167

def air_loop_hvac_multizone_vav_optimization_required?(air_loop_hvac, climate_zone)
  multizone_opt_required = false

  # Not required for systems with fan-powered terminals
  num_fan_powered_terminals = 0
  air_loop_hvac.demandComponents.each do |comp|
    if comp.to_AirTerminalSingleDuctParallelPIUReheat.is_initialized || comp.to_AirTerminalSingleDuctSeriesPIUReheat.is_initialized
      num_fan_powered_terminals += 1
    end
  end
  if num_fan_powered_terminals > 0
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}, multizone vav optimization is not required because the system has #{num_fan_powered_terminals} fan-powered terminals.")
    return multizone_opt_required
  end

  # Not required for systems that require an ERV
  if air_loop_hvac_energy_recovery?(air_loop_hvac)
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: multizone vav optimization is not required because the system has Energy Recovery.")
    return multizone_opt_required
  end

  # Get the OA intake
  controller_oa = nil
  controller_mv = nil
  oa_system = nil
  if air_loop_hvac.airLoopHVACOutdoorAirSystem.is_initialized
    oa_system = air_loop_hvac.airLoopHVACOutdoorAirSystem.get
    controller_oa = oa_system.getControllerOutdoorAir
    controller_mv = controller_oa.controllerMechanicalVentilation
  else
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}, multizone optimization is not applicable because system has no OA intake.")
    return multizone_opt_required
  end

  # Get the AHU design supply air flow rate
  dsn_flow_m3_per_s = nil
  if air_loop_hvac.designSupplyAirFlowRate.is_initialized
    dsn_flow_m3_per_s = air_loop_hvac.designSupplyAirFlowRate.get
  elsif air_loop_hvac.autosizedDesignSupplyAirFlowRate.is_initialized
    dsn_flow_m3_per_s = air_loop_hvac.autosizedDesignSupplyAirFlowRate.get
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name} design supply air flow rate is not available, cannot apply efficiency standard.")
    return multizone_opt_required
  end
  dsn_flow_cfm = OpenStudio.convert(dsn_flow_m3_per_s, 'm^3/s', 'cfm').get

  # Get the minimum OA flow rate
  min_oa_flow_m3_per_s = nil
  if controller_oa.minimumOutdoorAirFlowRate.is_initialized
    min_oa_flow_m3_per_s = controller_oa.minimumOutdoorAirFlowRate.get
  elsif controller_oa.autosizedMinimumOutdoorAirFlowRate.is_initialized
    min_oa_flow_m3_per_s = controller_oa.autosizedMinimumOutdoorAirFlowRate.get
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.AirLoopHVAC', "For #{controller_oa.name}: minimum OA flow rate is not available, cannot apply efficiency standard.")
    return multizone_opt_required
  end
  min_oa_flow_cfm = OpenStudio.convert(min_oa_flow_m3_per_s, 'm^3/s', 'cfm').get

  # Calculate the percent OA at design airflow
  pct_oa = min_oa_flow_m3_per_s / dsn_flow_m3_per_s

  # Not required for systems where
  # exhaust is more than 70% of the total OA intake.
  if pct_oa > 0.7
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{controller_oa.name}: multizone optimization is not applicable because system is more than 70% OA.")
    return multizone_opt_required
  end

  # TODO: Not required for dual-duct systems
  # if self.isDualDuct
  # OpenStudio::logFree(OpenStudio::Info, "openstudio.standards.AirLoopHVAC", "For #{controller_oa.name}: multizone optimization is not applicable because it is a dual duct system")
  # return multizone_opt_required
  # end

  # If here, multizone vav optimization is required
  multizone_opt_required = true

  return multizone_opt_required
end

#air_loop_hvac_single_zone_controls_num_stages(air_loop_hvac, climate_zone) ⇒ Integer

Determine the number of stages that should be used as controls for single zone DX systems. 90.1-2010 depends on the cooling capacity of the system.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 285

def air_loop_hvac_single_zone_controls_num_stages(air_loop_hvac, climate_zone)
  min_clg_cap_btu_per_hr = 65_000
  clg_cap_btu_per_hr = OpenStudio.convert(air_loop_hvac_total_cooling_capacity(air_loop_hvac), 'W', 'Btu/hr').get
  if clg_cap_btu_per_hr >= min_clg_cap_btu_per_hr
    num_stages = 2
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: two-stage control is required since cooling capacity of #{clg_cap_btu_per_hr.round} Btu/hr exceeds the minimum of #{min_clg_cap_btu_per_hr.round} Btu/hr .")
  else
    num_stages = 1
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: two-stage control is not required since cooling capacity of #{clg_cap_btu_per_hr.round} Btu/hr is less than the minimum of #{min_clg_cap_btu_per_hr.round} Btu/hr .")
  end

  return num_stages
end

#air_loop_hvac_supply_air_temperature_reset_required?(air_loop_hvac, climate_zone) ⇒ Bool

Determine if the system required supply air temperature (SAT) reset. For 90.1-2010, SAT reset requirements are based on climate zone.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb', line 304

def air_loop_hvac_supply_air_temperature_reset_required?(air_loop_hvac, climate_zone)
  is_sat_reset_required = false

  # Only required for multizone VAV systems
  unless air_loop_hvac_multizone_vav_system?(air_loop_hvac)
    return is_sat_reset_required
  end

  case climate_zone
  when 'ASHRAE 169-2006-1A',
    'ASHRAE 169-2006-2A',
    'ASHRAE 169-2006-3A'
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: Supply air temperature reset is not required per 6.5.3.4 Exception 1, the system is located in climate zone #{climate_zone}.")
    return is_sat_reset_required
  when 'ASHRAE 169-2006-1B',
    'ASHRAE 169-2006-2B',
    'ASHRAE 169-2006-3B',
    'ASHRAE 169-2006-3C',
    'ASHRAE 169-2006-4A',
    'ASHRAE 169-2006-4B',
    'ASHRAE 169-2006-4C',
    'ASHRAE 169-2006-5A',
    'ASHRAE 169-2006-5B',
    'ASHRAE 169-2006-5C',
    'ASHRAE 169-2006-6A',
    'ASHRAE 169-2006-6B',
    'ASHRAE 169-2006-7A',
    'ASHRAE 169-2006-7B',
    'ASHRAE 169-2006-8A',
    'ASHRAE 169-2006-8B'
    is_sat_reset_required = true
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: Supply air temperature reset is required.")
    return is_sat_reset_required
  end
end

#air_terminal_single_duct_vav_reheat_apply_initial_prototype_damper_position(air_terminal_single_duct_vav_reheat, building_type, zone_oa_per_area) ⇒ Bool

Set the initial minimum damper position based on OA rate of the space and the template. Zones with low OA per area get lower initial guesses. Final position will be adjusted upward as necessary by Standards.AirLoopHVAC.apply_minimum_vav_damper_positions


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb', line 11

def air_terminal_single_duct_vav_reheat_apply_initial_prototype_damper_position(air_terminal_single_duct_vav_reheat, building_type, zone_oa_per_area)
  vav_name = air_terminal_single_duct_vav_reheat.name.get
  min_damper_position = case air_terminal_single_duct_vav_reheat_reheat_type(air_terminal_single_duct_vav_reheat)
                        when 'HotWater'
                          0.2
                        when 'Electricity', 'NaturalGas'
                          0.3
                        end

  # High OA zones
  # Determine whether or not to use the high minimum guess.
  # Cutoff was determined by correlating apparent minimum guesses
  # to OA rates in prototypes since not well documented in papers.
  if zone_oa_per_area > 0.001 # 0.001 m^3/s*m^2 = .196 cfm/ft2
    if building_type == 'Outpatient'
      min_damper_position = 1.0
    elsif building_type == 'Hospital'
      if vav_name.include? 'PatRoom'
        min_damper_position = 0.5
      else
        min_damper_position = 1.0
        min_damper_position = 1.0
      end
    else
      min_damper_position = 0.7
    end
  end

  # Set the minimum flow fraction
  air_terminal_single_duct_vav_reheat.setConstantMinimumAirFlowFraction(min_damper_position)

  return true
end

#air_terminal_single_duct_vav_reheat_minimum_damper_position(air_terminal_single_duct_vav_reheat, has_ddc = false) ⇒ Object

Specifies the minimum damper position for VAV dampers. For terminals with hot water heat and DDC, the minimum is 20%, otherwise the minimum is 30%.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb', line 9

def air_terminal_single_duct_vav_reheat_minimum_damper_position(air_terminal_single_duct_vav_reheat, has_ddc = false)
  min_damper_position = nil
  case air_terminal_single_duct_vav_reheat_reheat_type(air_terminal_single_duct_vav_reheat)
  when 'HotWater'
    min_damper_position = if has_ddc
                            0.2
                          else
                            0.3
                          end
  when 'Electricity', 'NaturalGas'
    min_damper_position = 0.3
  end

  return min_damper_position
end

#cooling_tower_apply_minimum_power_per_flow_gpm_limit(cooling_tower) ⇒ Double Originally defined in module ASHRAE9012010CoolingTower

Above this point, centrifugal fan cooling towers must meet the limits of propeller or axial cooling towers instead. 90.1 6.5.5.3 Limit on Centrifugal Fan Open Circuit Cooling Towers. is 1,100 gallons per minute.

OpenStudio::Model::CoolingTowerTwoSpeed, OpenStudio::Model::CoolingTowerVariableSpeed] the cooling tower

#fan_constant_volume_airloop_fan_pressure_rise(fan_constant_volume) ⇒ Double

Determine the prototype fan pressure rise for a constant volume fan on an AirLoopHVAC based on the airflow of the system. to the logic from ASHRAE 90.1-2004 prototypes.


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanConstantVolume.rb', line 8

def fan_constant_volume_airloop_fan_pressure_rise(fan_constant_volume)
  # Get the max flow rate from the fan.
  maximum_flow_rate_m3_per_s = nil
  if fan_constant_volume.maximumFlowRate.is_initialized
    maximum_flow_rate_m3_per_s = fan_constant_volume.maximumFlowRate.get
  elsif fan_constant_volume.autosizedMaximumFlowRate.is_initialized
    maximum_flow_rate_m3_per_s = fan_constant_volume.autosizedMaximumFlowRate.get
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.prototype.FanConstantVolume', "For #{fan_constant_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 < 7437
                           2.5
                         else # Over 7,437 cfm
                           4.09
                         end

  return pressure_rise_in_h2o
end

#fan_on_off_airloop_or_unitary_fan_pressure_rise(fan_on_off) ⇒ Double

Determine the prototype fan pressure rise for an on off fan on an AirLoopHVAC or inside a unitary system based on the airflow of the system. to the logic from ASHRAE 90.1-2004 prototypes.


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanOnOff.rb', line 9

def fan_on_off_airloop_or_unitary_fan_pressure_rise(fan_on_off)
  # Get the max flow rate from the fan.
  maximum_flow_rate_m3_per_s = nil
  if fan_on_off.maximumFlowRate.is_initialized
    maximum_flow_rate_m3_per_s = fan_on_off.maximumFlowRate.get
  elsif fan_on_off.autosizedMaximumFlowRate.is_initialized
    maximum_flow_rate_m3_per_s = fan_on_off.autosizedMaximumFlowRate.get
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.prototype.FanOnOff', "For #{fan_on_off.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 < 7437
                           2.5
                         else # Over 7,437 cfm
                           4.09
                         end

  return pressure_rise_in_h2o
end

#fan_variable_volume_airloop_fan_pressure_rise(fan_variable_volume) ⇒ Double

Determine the prototype fan pressure rise for a variable volume fan on an AirLoopHVAC based on the airflow of the system. to the logic from ASHRAE 90.1-2004 prototypes.


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanVariableVolume.rb', line 8

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
                         else # Over 7,437 cfm
                           5.58
                         end

  return pressure_rise_in_h2o
end

#fan_variable_volume_part_load_fan_power_limitation_hp_limit(fan_variable_volume) ⇒ Double

TODO:

AddRef

The threhold horsepower below which part load control is not required. 10 nameplate HP threshold is equivalent to motors with input powers of 7.54 HP per TSD


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanVariableVolume.rb', line 10

def fan_variable_volume_part_load_fan_power_limitation_hp_limit(fan_variable_volume)
  hp_limit = 7.54
  return hp_limit
end

#model_create_prm_baseline_building_requires_vlt_sizing_run(model) ⇒ Object

Determine if there needs to be a sizing run after constructions are added so that EnergyPlus can calculate the VLTs of layer-by-layer glazing constructions. These VLT values are needed for the daylighting controls logic for 90.1-2010.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb', line 8

def model_create_prm_baseline_building_requires_vlt_sizing_run(model)
  return true # Required for 90.1-2010
end

#model_economizer_type(model, climate_zone) ⇒ String

Determine the prototypical economizer type for the model.

'NoEconomizer' 'FixedDryBulb' 'FixedEnthalpy' 'DifferentialDryBulb' 'DifferentialEnthalpy' 'FixedDewPointAndDryBulb' 'ElectronicEnthalpy' 'DifferentialDryBulbAndEnthalpy'


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb', line 17

def model_economizer_type(model, climate_zone)
  economizer_type = case climate_zone
                    when 'ASHRAE 169-2006-1A',
                        'ASHRAE 169-2006-2A',
                        'ASHRAE 169-2006-3A',
                        'ASHRAE 169-2006-4A'
                      'DifferentialEnthalpy'
                    else
                      'DifferentialDryBulb'
                    end
  return economizer_type
end

#model_elevator_lighting_pct_incandescent(model) ⇒ Object

Determines the percentage of the elevator cab lighting that is incandescent. The remainder is assumed to be LED. Defaults to 0% incandescent (100% LED), representing newer elevators.


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# File 'lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.elevators.rb', line 8

def model_elevator_lighting_pct_incandescent(model)
  pct_incandescent = 0.0 # 100% LED
  return pct_incandescent
end

#model_prm_baseline_system_number(model, climate_zone, area_type, fuel_type, area_ft2, num_stories, custom) ⇒ String

Determines which system number is used for the baseline system. 5_or_6, 7_or_8, 9_or_10


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb', line 16

def model_prm_baseline_system_number(model, climate_zone, area_type, fuel_type, area_ft2, num_stories, custom)
  sys_num = nil

  # Set the area limit
  limit_ft2 = 25_000

  # Customization for Xcel EDA.
  # No special retail category
  # for regular 90.1-2010.
  unless custom == 'Xcel Energy CO EDA'
    if area_type == 'retail'
      area_type = 'nonresidential'
    end
  end

  case area_type
  when 'residential'
    sys_num = '1_or_2'
  when 'nonresidential'    # nonresidential and 3 floors or less and <25,000 ft2

    if num_stories <= 3 && area_ft2 < limit_ft2
      sys_num = '3_or_4'    # nonresidential and 4 or 5 floors or 5 floors or less and 25,000 ft2 to 150,000 ft2

    elsif ((num_stories == 4 || num_stories == 5) && area_ft2 < limit_ft2) || (num_stories <= 5 && (area_ft2 >= limit_ft2 && area_ft2 <= 150_000))
      sys_num = '5_or_6'    # nonresidential and more than 5 floors or >150,000 ft2

    elsif num_stories >= 5 || area_ft2 > 150_000
      sys_num = '7_or_8'
    end
  when 'heatedonly'
    sys_num = '9_or_10'
  when 'retail'    # Should only be hit by Xcel EDA

    sys_num = '3_or_4'
  end

  return sys_num
end

#space_daylighted_area_window_width(space) ⇒ String

Determines the method used to extend the daylighted area horizontally next to a window. If the method is 'fixed', 2 ft is added to the width of each window. If the method is 'proportional', a distance equal to half of the head height of the window is added. If the method is 'none', no additional width is added.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb', line 11

def space_daylighted_area_window_width(space)
  method = 'fixed'
  return method
end

#space_daylighting_control_required?(space, areas) ⇒ Array<Bool>

Determine if the space requires daylighting controls for toplighting, primary sidelighting, and secondary sidelighting. Defaults to false for all types.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb', line 23

def space_daylighting_control_required?(space, areas)
  req_top_ctrl = true
  req_pri_ctrl = true
  req_sec_ctrl = false

  OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "primary_sidelighted_area = #{areas['primary_sidelighted_area']}")

  # Sidelighting
  # Check if the primary sidelit area < 250 ft2
  if areas['primary_sidelighted_area'] == 0.0
    OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "For #{space.name}, primary sidelighting control not required because primary sidelighted area = 0ft2 per 9.4.1.4.")
    req_pri_ctrl = false
  elsif areas['primary_sidelighted_area'] < OpenStudio.convert(250, 'ft^2', 'm^2').get
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.Space', "For #{space.name}, primary sidelighting control not required because primary sidelighted area < 250ft2 per 9.4.1.4.")
    req_pri_ctrl = false
  else
    # Check effective sidelighted aperture
    sidelighted_effective_aperture = space_sidelighting_effective_aperture(space, areas['primary_sidelighted_area'])
    OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "sidelighted_effective_aperture_pri = #{sidelighted_effective_aperture}")
    if sidelighted_effective_aperture < 0.1
      OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.Space', "For #{space.name}, primary sidelighting control not required because sidelighted effective aperture < 0.1 per 9.4.1.4 Exception b.")
      req_pri_ctrl = false
    end
  end

  OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "toplighted_area = #{areas['toplighted_area']}")

  # Toplighting
  # Check if the toplit area < 900 ft2
  if areas['toplighted_area'] == 0.0
    OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "For #{space.name}, toplighting control not required because toplighted area = 0ft2 per 9.4.1.5.")
    req_top_ctrl = false
  elsif areas['toplighted_area'] < OpenStudio.convert(900, 'ft^2', 'm^2').get
    OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.Space', "For #{space.name}, toplighting control not required because toplighted area < 900ft2 per 9.4.1.5.")
    req_top_ctrl = false
  else
    # Check effective sidelighted aperture
    sidelighted_effective_aperture = space_skylight_effective_aperture(space, areas['toplighted_area'])
    OpenStudio.logFree(OpenStudio::Debug, 'openstudio.model.Space', "sidelighted_effective_aperture_top = #{sidelighted_effective_aperture}")
    if sidelighted_effective_aperture < 0.006
      OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.Space', "For #{space.name}, toplighting control not required because skylight effective aperture < 0.006 per 9.4.1.5 Exception b.")
      req_top_ctrl = false
    end
  end

  return [req_top_ctrl, req_pri_ctrl, req_sec_ctrl]
end

#space_daylighting_fractions_and_windows(space, areas, sorted_windows, sorted_skylights, req_top_ctrl, req_pri_ctrl, req_sec_ctrl) ⇒ Object

Determine the fraction controlled by each sensor and which window each sensor should go near.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb', line 80

def space_daylighting_fractions_and_windows(space,
                                            areas,
                                            sorted_windows,
                                            sorted_skylights,
                                            req_top_ctrl,
                                            req_pri_ctrl,
                                            req_sec_ctrl)
  sensor_1_frac = 0.0
  sensor_2_frac = 0.0
  sensor_1_window = nil
  sensor_2_window = nil

  # Get the area of the space
  space_area_m2 = space.floorArea

  if req_top_ctrl && req_pri_ctrl    # Sensor 1 controls toplighted area

    sensor_1_frac = areas['toplighted_area'] / space_area_m2
    sensor_1_window = sorted_skylights[0]    # Sensor 2 controls primary area

    sensor_2_frac = areas['primary_sidelighted_area'] / space_area_m2
    sensor_2_window = sorted_windows[0]
  elsif req_top_ctrl && !req_pri_ctrl    # Sensor 1 controls toplighted area

    sensor_1_frac = areas['toplighted_area'] / space_area_m2
    sensor_1_window = sorted_skylights[0]
  elsif !req_top_ctrl && req_pri_ctrl
    if sorted_windows.size == 1      # Sensor 1 controls the whole primary area

      sensor_1_frac = areas['primary_sidelighted_area'] / space_area_m2
      sensor_1_window = sorted_windows[0]
    else
      # Sensor 1 controls half the primary area
      sensor_1_frac = (areas['primary_sidelighted_area'] / space_area_m2) / 2
      sensor_1_window = sorted_windows[0]      # Sensor 2 controls the other half of primary area

      sensor_2_frac = (areas['primary_sidelighted_area'] / space_area_m2) / 2
      sensor_2_window = sorted_windows[1]
    end
  end

  return [sensor_1_frac, sensor_2_frac, sensor_1_window, sensor_2_window]
end

#space_infiltration_rate_75_pa(space) ⇒ Double

Determine the base infiltration rate at 75 PA.

defaults to no infiltration.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb', line 128

def space_infiltration_rate_75_pa(space)
  basic_infil_rate_cfm_per_ft2 = 1.0
  return basic_infil_rate_cfm_per_ft2
end

#thermal_zone_demand_control_ventilation_limits(thermal_zone) ⇒ Array<Double>

Determine the area and occupancy level limits for demand control ventilation.

and the minimum occupancy density in m^2/person. Returns nil if there is no requirement.


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# File 'lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.ThermalZone.rb', line 11

def thermal_zone_demand_control_ventilation_limits(thermal_zone)
  min_area_ft2 = 500
  min_occ_per_1000_ft2 = 40

  # Convert to SI
  min_area_m2 = OpenStudio.convert(min_area_ft2, 'ft^2', 'm^2').get
  min_occ_per_ft2 = min_occ_per_1000_ft2 / 1000.0
  min_ft2_per_occ = 1.0 / min_occ_per_ft2
  min_m2_per_occ = OpenStudio.convert(min_ft2_per_occ, 'ft^2', 'm^2').get

  return [min_area_m2, min_m2_per_occ]
end