class ASHRAE9012010

This class holds methods that apply ASHRAE 90.1-2010 to a given model. @ref [References::ASHRAE9012010]

Attributes

template[R]

Public Class Methods

new() click to toggle source
# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.rb, line 8
def initialize
  @template = '90.1-2010'
  load_standards_database
end

Public Instance Methods

air_loop_hvac_demand_control_ventilation_limits(air_loop_hvac) click to toggle source

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.

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @return [Array<Double>] [min_oa_without_economizer_cfm, min_oa_with_economizer_cfm]

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 233
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) click to toggle source

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

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Array<Double>] [drybulb_limit_f, enthalpy_limit_btu_per_lb, dewpoint_limit_f]

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 9
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
  return [nil, nil, nil] unless oa_sys.is_initialized # No OA system

  oa_sys = oa_sys.get
  oa_control = oa_sys.getControllerOutdoorAir
  economizer_type = oa_control.getEconomizerControlType

  case economizer_type
  when 'NoEconomizer'
    return [nil, nil, nil]
  when 'FixedDryBulb'
    search_criteria = {
      'template' => template,
      'climate_zone' => climate_zone
    }
    econ_limits = model_find_object(standards_data['economizers'], search_criteria)
    drybulb_limit_f = econ_limits['fixed_dry_bulb_high_limit_shutoff_temp']
  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) click to toggle source

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

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Boolean] Returns true if allowable, if the system has no economizer or no OA system.

Returns false if the economizer type is not allowable.
# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 59
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
  return true unless oa_sys.is_initialized

  oa_sys = oa_sys.get
  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 169-2006-0B',
       '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',
       'ASHRAE 169-2013-0B',
       'ASHRAE 169-2013-1B',
       'ASHRAE 169-2013-2B',
       'ASHRAE 169-2013-3B',
       'ASHRAE 169-2013-3C',
       'ASHRAE 169-2013-4B',
       'ASHRAE 169-2013-4C',
       'ASHRAE 169-2013-5B',
       'ASHRAE 169-2013-6B',
       'ASHRAE 169-2013-7A',
       'ASHRAE 169-2013-7B',
       'ASHRAE 169-2013-8A',
       'ASHRAE 169-2013-8B'
    prohibited_types = ['FixedEnthalpy']
  when 'ASHRAE 169-2006-0A',
       'ASHRAE 169-2006-1A',
       'ASHRAE 169-2006-2A',
       'ASHRAE 169-2006-3A',
       'ASHRAE 169-2006-4A',
       'ASHRAE 169-2013-0A',
       'ASHRAE 169-2013-1A',
       'ASHRAE 169-2013-2A',
       'ASHRAE 169-2013-3A',
       'ASHRAE 169-2013-4A'
    prohibited_types = ['FixedDryBulb', 'DifferentialDryBulb']
  when 'ASHRAE 169-2006-5A',
       'ASHRAE 169-2006-6A',
       'ASHRAE 169-2013-5A',
       'ASHRAE 169-2013-6A'
    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) click to toggle source

Determine the airflow limits that govern whether or not an ERV is required. Based on climate zone and % OA.

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @param pct_oa [Double] percentage of outdoor air @return [Double] the flow rate above which an ERV is required. if nil, ERV is never required.

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 366
def air_loop_hvac_energy_recovery_ventilator_flow_limit(air_loop_hvac, climate_zone, pct_oa)
  # Table 6.5.6.1
  search_criteria = {
    'template' => template,
    'climate_zone' => climate_zone
  }
  energy_recovery_limits = model_find_object(standards_data['energy_recovery'], search_criteria)
  if energy_recovery_limits.nil?
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.ashrae_90_1_2010.AirLoopHVAC', "Cannot find energy recovery limits for template '#{template}', climate zone '#{climate_zone}', assuming no energy recovery required.")
    return nil
  end

  if pct_oa < 0.1
    erv_cfm = nil
  elsif pct_oa >= 0.1 && pct_oa < 0.2
    erv_cfm = nil
  elsif pct_oa >= 0.2 && pct_oa < 0.3
    erv_cfm = energy_recovery_limits['20_to_30_percent_oa']
  elsif pct_oa >= 0.3 && pct_oa < 0.4
    erv_cfm = energy_recovery_limits['30_to_40_percent_oa']
  elsif pct_oa >= 0.4 && pct_oa < 0.5
    erv_cfm = energy_recovery_limits['40_to_50_percent_oa']
  elsif pct_oa >= 0.5 && pct_oa < 0.6
    erv_cfm = energy_recovery_limits['50_to_60_percent_oa']
  elsif pct_oa >= 0.6 && pct_oa < 0.7
    erv_cfm = energy_recovery_limits['60_to_70_percent_oa']
  elsif pct_oa >= 0.7 && pct_oa < 0.8
    erv_cfm = energy_recovery_limits['70_to_80_percent_oa']
  elsif pct_oa >= 0.8
    erv_cfm = energy_recovery_limits['greater_than_80_percent_oa']
  end

  return erv_cfm
end
air_loop_hvac_integrated_economizer_required?(air_loop_hvac, climate_zone) click to toggle source

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

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Boolean] returns true if required, false if not

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 48
def air_loop_hvac_integrated_economizer_required?(air_loop_hvac, climate_zone)
  return true
end
air_loop_hvac_motorized_oa_damper_limits(air_loop_hvac, climate_zone) click to toggle source

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

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Array<Double>] [minimum_oa_flow_cfm, maximum_stories]. If both nil, never required

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 244
def air_loop_hvac_motorized_oa_damper_limits(air_loop_hvac, climate_zone)
  case climate_zone
  when 'ASHRAE 169-2006-0A',
       'ASHRAE 169-2006-1A',
       'ASHRAE 169-2006-0B',
       'ASHRAE 169-2006-1B',
       'ASHRAE 169-2006-2A',
       'ASHRAE 169-2006-2B',
       'ASHRAE 169-2006-3A',
       'ASHRAE 169-2006-3B',
       'ASHRAE 169-2006-3C',
       'ASHRAE 169-2013-0A',
       'ASHRAE 169-2013-1A',
       'ASHRAE 169-2013-0B',
       'ASHRAE 169-2013-1B',
       'ASHRAE 169-2013-2A',
       'ASHRAE 169-2013-2B',
       'ASHRAE 169-2013-3A',
       'ASHRAE 169-2013-3B',
       'ASHRAE 169-2013-3C'
    minimum_oa_flow_cfm = 0
    maximum_stories = 999 # Any number of stories
  else
    minimum_oa_flow_cfm = 0
    maximum_stories = 0
  end

  return [minimum_oa_flow_cfm, maximum_stories]
end
air_loop_hvac_multizone_vav_optimization_required?(air_loop_hvac, climate_zone) click to toggle source

Determine if multizone vav optimization is required. @note code_sections [90.1-2010_6.5.3.3]

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Boolean] returns true if required, false if not @todo Add exception logic for systems with AIA healthcare ventilation requirements dual duct systems

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 147
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
  # Exception 2 to Section 6.5.3.3
  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) click to toggle source

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.

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Integer] the number of stages: 0, 1, 2

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 280
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) click to toggle source

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

@param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Boolean] returns true if required, false if not

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirLoopHVAC.rb, line 300
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 169-2006-0A',
       'ASHRAE 169-2006-1A',
       'ASHRAE 169-2006-2A',
       'ASHRAE 169-2006-3A',
       'ASHRAE 169-2013-0A',
       'ASHRAE 169-2013-1A',
       'ASHRAE 169-2013-2A',
       'ASHRAE 169-2013-3A'
    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 169-2006-0B',
       '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',
       'ASHRAE 169-2013-0B',
       'ASHRAE 169-2013-1B',
       'ASHRAE 169-2013-2B',
       'ASHRAE 169-2013-3B',
       'ASHRAE 169-2013-3C',
       'ASHRAE 169-2013-4A',
       'ASHRAE 169-2013-4B',
       'ASHRAE 169-2013-4C',
       'ASHRAE 169-2013-5A',
       'ASHRAE 169-2013-5B',
       'ASHRAE 169-2013-5C',
       'ASHRAE 169-2013-6A',
       'ASHRAE 169-2013-6B',
       'ASHRAE 169-2013-7A',
       'ASHRAE 169-2013-7B',
       'ASHRAE 169-2013-8A',
       'ASHRAE 169-2013-8B'
    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, zone_oa_per_area) click to toggle source

@!group AirTerminalSingleDuctVAVReheat 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

@param air_terminal_single_duct_vav_reheat [OpenStudio::Model::AirTerminalSingleDuctVAVReheat] the air terminal object @param zone_oa_per_area [Double] the zone outdoor air per area in m^3/s*m^2 @return [Boolean] returns true if successful, false if not

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb, line 10
def air_terminal_single_duct_vav_reheat_apply_initial_prototype_damper_position(air_terminal_single_duct_vav_reheat, zone_oa_per_area)
  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

  # 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) click to toggle source

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%.

@param air_terminal_single_duct_vav_reheat [OpenStudio::Model::AirTerminalSingleDuctVAVReheat] the air terminal object @param has_ddc [Boolean] whether or not there is DDC control of the VAV terminal in question @return [Double] minimum damper position

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.AirTerminalSingleDuctVAVReheat.rb, line 10
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
boiler_get_eff_fplr(boiler_hot_water) click to toggle source

Determine what part load efficiency degredation curve should be used for a boiler

@param boiler_hot_water [OpenStudio::Model::BoilerHotWater] hot water boiler object @return [String] returns name of the boiler curve to be used, or nil if not applicable

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.BoilerHotWater.rb, line 6
def boiler_get_eff_fplr(boiler_hot_water)
  return 'Boiler with No Minimum Turndown'
end
chiller_electric_eir_get_cap_f_t_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path) click to toggle source

Get applicable performance curve for capacity as a function of temperature

@param chiller_electric_eir [OpenStudio::Model::ChillerElectricEIR] chiller object @param compressor_type [String] compressor type @param cooling_type [String] cooling type (‘AirCooled’ or ‘WaterCooled’) @param chiller_tonnage [Double] chiller capacity in ton @return [String] name of applicable cuvre, nil if not found @todo the current assingment is meant to replicate what was in the data, it probably needs to be reviewed

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.ChillerElectricEIR.rb, line 10
def chiller_electric_eir_get_cap_f_t_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path)
  case cooling_type
  when 'AirCooled'
    return 'AirCooled_Chiller_2010_PathA_CAPFT'
  when 'WaterCooled'
    case compressor_type
    when 'Centrifugal'
      if chiller_tonnage >= 150
        return 'WaterCooled_Centrifugal_Chiller_GT150_2004_CAPFT'
      else
        return 'WaterCooled_Centrifugal_Chiller_LT150_2004_CAPFT'
      end
    when 'Reciprocating', 'Rotary Screw', 'Scroll'
      if chiller_tonnage >= 150
        return 'WaterCooled_PositiveDisplacement_Chiller_GT150_2010_PathA_CAPFT' # 2010 reference might suggest that this is the wrong curve
      else
        return 'WaterCooled_PositiveDisplacement_Chiller_LT150_2010_PathA_CAPFT' # 2010 reference might suggest that this is the wrong curve
      end
    else
      return nil
    end
  else
    return nil
  end
end
chiller_electric_eir_get_eir_f_plr_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path) click to toggle source

Get applicable performance curve for EIR as a function of part load ratio

@param chiller_electric_eir [OpenStudio::Model::ChillerElectricEIR] chiller object @param compressor_type [String] compressor type @param cooling_type [String] cooling type (‘AirCooled’ or ‘WaterCooled’) @param chiller_tonnage [Double] chiller capacity in ton @return [String] name of applicable cuvre, nil if not found @todo the current assingment is meant to replicate what was in the data, it probably needs to be reviewed

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.ChillerElectricEIR.rb, line 78
def chiller_electric_eir_get_eir_f_plr_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path)
  case cooling_type
  when 'AirCooled'
    return 'AirCooled_Chiller_AllCapacities_2004_2010_EIRFPLR'
  when 'WaterCooled'
    case compressor_type
    when 'Centrifugal'
      return 'ChlrWtrCentPathAAllEIRRatio_fQRatio'
    when 'Reciprocating', 'Rotary Screw', 'Scroll'
      return 'ChlrWtrPosDispPathAAllEIRRatio_fTchwsTcwsSI'
    else
      return nil
    end
  else
    return nil
  end
end
chiller_electric_eir_get_eir_f_t_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path) click to toggle source

Get applicable performance curve for EIR as a function of temperature

@param chiller_electric_eir [OpenStudio::Model::ChillerElectricEIR] chiller object @param compressor_type [String] compressor type @param cooling_type [String] cooling type (‘AirCooled’ or ‘WaterCooled’) @param chiller_tonnage [Double] chiller capacity in ton @return [String] name of applicable cuvre, nil if not found @todo the current assingment is meant to replicate what was in the data, it probably needs to be reviewed

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.ChillerElectricEIR.rb, line 44
def chiller_electric_eir_get_eir_f_t_curve_name(chiller_electric_eir, compressor_type, cooling_type, chiller_tonnage, compliance_path)
  case cooling_type
  when 'AirCooled'
    return 'AirCooled_Chiller_2010_PathA_EIRFT'
  when 'WaterCooled'
    case compressor_type
    when 'Centrifugal'
      if chiller_tonnage >= 150
        return 'WaterCooled_Centrifugal_Chiller_GT150_2004_EIRFT'
      else
        return 'WaterCooled_Centrifugal_Chiller_LT150_2004_EIRFT'
      end
    when 'Reciprocating', 'Rotary Screw', 'Scroll'
      if chiller_tonnage >= 150
        return 'WaterCooled_PositiveDisplacement_Chiller_GT150_2010_PathA_EIRFT' # 2010 reference might suggest that this is the wrong curve
      else
        return 'WaterCooled_PositiveDisplacement_Chiller_LT150_2010_PathA_EIRFT' # 2010 reference might suggest that this is the wrong curve
      end
    else
      return nil
    end
  else
    return nil
  end
end
fan_constant_volume_airloop_fan_pressure_rise(fan_constant_volume) click to toggle source

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

@param fan_constant_volume [OpenStudio::Model::FanConstantVolume] constant volume fan object @return [Double] pressure rise in inches H20

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanConstantVolume.rb, line 9
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) click to toggle source

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

@param fan_on_off [OpenStudio::Model::FanOnOff] on off fan object @return [Double] pressure rise in inches H20

# 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) click to toggle source

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

@param fan_variable_volume [OpenStudio::Model::FanVariableVolume] variable volume fan object @return [Double] pressure rise in inches H20

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.FanVariableVolume.rb, line 9
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) click to toggle source

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

@param fan_variable_volume [OpenStudio::Model::FanVariableVolume] variable volume fan object @return [Double] the limit, in horsepower. Return nil for no limit by default. @todo AddRef

# 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
load_standards_database(data_directories = []) click to toggle source

Loads the openstudio standards dataset for this standard.

@param data_directories [Array<String>] array of file paths that contain standards data @return [Hash] a hash of standards data

Calls superclass method ASHRAE901#load_standards_database
# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.rb, line 17
def load_standards_database(data_directories = [])
  super([__dir__] + data_directories)
end
model_create_prm_baseline_building_requires_vlt_sizing_run(model) click to toggle source

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.

# 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) click to toggle source

Determine the prototypical economizer type for the model.

@param model [OpenStudio::Model::Model] OpenStudio model object @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [String] the economizer type. Possible values are: ‘NoEconomizer’ ‘FixedDryBulb’ ‘FixedEnthalpy’ ‘DifferentialDryBulb’ ‘DifferentialEnthalpy’ ‘FixedDewPointAndDryBulb’ ‘ElectronicEnthalpy’ ‘DifferentialDryBulbAndEnthalpy’

# 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 169-2006-0A',
                        'ASHRAE 169-2006-1A',
                        'ASHRAE 169-2006-2A',
                        'ASHRAE 169-2006-3A',
                        'ASHRAE 169-2006-4A',
                        'ASHRAE 169-2013-0A',
                        'ASHRAE 169-2013-1A',
                        'ASHRAE 169-2013-2A',
                        'ASHRAE 169-2013-3A',
                        'ASHRAE 169-2013-4A'
                      'DifferentialEnthalpy'
                    else
                      'DifferentialDryBulb'
                    end
  return economizer_type
end
model_elevator_lighting_pct_incandescent(model) click to toggle source

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.

@param model [OpenStudio::Model::Model] OpenStudio model object @return [Double] incandescent lighting percentage

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.elevators.rb, line 10
def model_elevator_lighting_pct_incandescent(model)
  pct_incandescent = 0.0 # 100% LED
  return pct_incandescent
end
model_fenestration_orientation(model, climate_zone) click to toggle source

Adjust model to comply with fenestration orientation requirements @note code_sections [90.1-2010_5.5.4.5]

@param model [OpenStudio::Model::Model] OpenStudio model object @param climate_zone [String] ASHRAE climate zone, e.g. ‘ASHRAE 169-2013-4A’ @return [Boolean] Returns true if successful, false otherwise

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb, line 42
def model_fenestration_orientation(model, climate_zone)
  wwr = false

  win_area_w = OpenstudioStandards::Geometry.model_get_exterior_window_and_wall_area_by_orientation(model)['west_window']
  win_area_e = OpenstudioStandards::Geometry.model_get_exterior_window_and_wall_area_by_orientation(model)['east_window']
  win_area_s = OpenstudioStandards::Geometry.model_get_exterior_window_and_wall_area_by_orientation(model)['south_window']

  # Make prototype specific adjustment to meet the code requirement
  if !((win_area_s > win_area_w) && (win_area_s > win_area_e))
    if model.getBuilding.standardsBuildingType.is_initialized
      building_type = model.getBuilding.standardsBuildingType.get

      case building_type
        # @todo Implementatation for other building types not meeting the requirement
        #   The offices, schools, warehouse (exempted), large hotel, outpatient,
        #   retails, apartments should meet the requirement according to Section
        #   5.2.1.7 in Thornton et al. 2011
        when 'Hospital'
          # Rotate the building counter-clockwise
          OpenstudioStandards::Geometry.model_set_building_north_axis(model, 270.0)
        when 'SmallHotel'
          # Rotate the building clockwise
          OpenstudioStandards::Geometry.model_set_building_north_axis(model, 180.0)
        else
          OpenStudio.logFree(OpenStudio::Warn, 'openstudio.model.ashrae_90_1_2010', "The prototype model doesn't meet the requirement from Section 5.5.4.5 in ASHRAE Standard 90.1-2010.")
      end
    else
      OpenStudio.logFree(OpenStudio::Warn, 'openstudio.model.ashrae_90_1_2010', "The prototype model doesn't meet the requirement from Section 5.5.4.5 in ASHRAE Standard 90.1-2010, its standards building type shall be specified.")
    end
  end

  return true
end
model_prm_baseline_system_number(model, climate_zone, area_type, fuel_type, area_ft2, num_stories, custom) click to toggle source

Determines which system number is used for the baseline system. @return [String] the system number: 1_or_2, 3_or_4, 5_or_6, 7_or_8, 9_or_10

# 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
model_transfer_air_required?(model) click to toggle source

Is transfer air required? @note code_sections [90.1-2010_6.5.7.1.2]

@param model [OpenStudio::Model::Model] OpenStudio model object @return [Boolean] true if transfer air is required, false otherwise

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Model.rb, line 81
def model_transfer_air_required?(model)
  # @todo It actually is for kitchen but not implemented yet
  return false
end
pump_variable_speed_get_control_type(pump, plant_loop_type, pump_nominal_hp) click to toggle source

Determine type of pump part load control type @note code_sections [90.1-2010_6.5.4.1]

@param pump [OpenStudio::Model::PumpVariableSpeed] OpenStudio pump object @param plant_loop_type [String] Type of plant loop @param pump_nominal_hp [Float] Pump nominal horsepower @return [String] Pump part load control type

# File lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.PumpVariableSpeed.rb, line 11
def pump_variable_speed_get_control_type(pump, plant_loop_type, pump_nominal_hp)
  threshold = 5 # hp

  # Sizing factor to take into account that pumps
  # are typically sized to handle a ~10% pressure
  # increase and ~10% flow increase.
  design_sizing_factor = 1.25

  return 'Riding Curve' if plant_loop_type == 'Heating'

  # Requirement only applies to CHW pumps
  return 'VSD DP Reset' if pump_nominal_hp * design_sizing_factor > threshold

  # else
  return 'Riding Curve'
end
space_daylighted_area_window_width(space) click to toggle source

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.

@return [String] returns ‘fixed’ or ‘proportional’

# 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) click to toggle source

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

@param space [OpenStudio::Model::Space] the space in question @param areas [Hash] a hash of daylighted areas @return [Array<Bool>] req_top_ctrl, req_pri_ctrl, req_sec_ctrl

# 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 less than 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 && @instvarbuilding_type.nil?
      OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.Space', "For #{space.name}, primary sidelighting control not required because sidelighted effective aperture less than 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 less than 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 less than 0.006 per 9.4.1.5 Exception b.")
      req_top_ctrl = false
    end
  end

  # Exceptions
  if space.spaceType.is_initialized
    case space.spaceType.get.standardsSpaceType.to_s
    # Retail spaces exception (c) to Section 9.4.1.4
    # req_sec_ctrl set to true to create a second reference point
    when 'Core_Retail'
      req_pri_ctrl = false
      req_sec_ctrl = true
    when 'Entry', 'Front_Retail', 'Point_of_Sale'
      req_pri_ctrl = false
      req_sec_ctrl = false
    # Strip mall
    when 'Strip mall - type 1', 'Strip mall - type 2', 'Strip mall - type 3'
      req_pri_ctrl = false
      req_sec_ctrl = false
    # Residential apartments
    when 'Apartment', 'Apartment_topfloor_NS', 'Apartment_topfloor_WE'
      req_top_ctrl = false
      req_pri_ctrl = false
      req_sec_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) click to toggle source

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

@param space [OpenStudio::Model::Space] space object @param areas [Hash] a hash of daylighted areas @param sorted_windows [Hash] a hash of windows, sorted by priority @param sorted_skylights [Hash] a hash of skylights, sorted by priority @param req_top_ctrl [Boolean] if toplighting controls are required @param req_pri_ctrl [Boolean] if primary sidelighting controls are required @param req_sec_ctrl [Boolean] if secondary sidelighting controls are required @return [Array] array of 4 items

[sensor 1 fraction, sensor 2 fraction, sensor 1 window, sensor 2 window]
# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb, line 105
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

  # get the climate zone
  climate_zone = OpenstudioStandards::Weather.model_get_climate_zone(space.model)

  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 && req_sec_ctrl
    # Sensor 1 controls toplighted area
    sensor_1_frac = areas['toplighted_area'] / space_area_m2
    sensor_1_window = sorted_skylights[0]
    # Sensor 2 controls secondary area
    sensor_2_frac = (areas['secondary_sidelighted_area'] / space_area_m2)
    # sorted_skylights[0] assigned to sensor_2_window so a second reference point is added for top daylighting
    sensor_2_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 = nil) click to toggle source

Determine the base infiltration rate at 75 Pa.

@return [Double] the baseline infiltration rate, in cfm/ft^2 defaults to no infiltration.

# File lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2010/ashrae_90_1_2010.Space.rb, line 164
def space_infiltration_rate_75_pa(space = nil)
  basic_infil_rate_cfm_per_ft2 = 1.0
  return basic_infil_rate_cfm_per_ft2
end
thermal_zone_demand_control_ventilation_limits(thermal_zone) click to toggle source

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

@param thermal_zone [OpenStudio::Model::ThermalZone] the thermal zone @return [Array<Double>] the minimum area, in m^2 and the minimum occupancy density in m^2/person. Returns nil if there is no requirement.

# 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