Class: SetSpaceInfiltrationByExteriorSurfaceArea

Inherits:
OpenStudio::Measure::ModelMeasure
  • Object
show all
Defined in:
lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb

Overview

start the measure

Instance Method Summary collapse

Instance Method Details

#arguments(model) ⇒ Object

define the arguments that the user will input



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# File 'lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb', line 14

def arguments(model)
  args = OpenStudio::Measure::OSArgumentVector.new

  # make an argument for infiltration
  infiltration_ip = OpenStudio::Measure::OSArgument.makeDoubleArgument('infiltration_ip', true)
  infiltration_ip.setDisplayName('Space Infiltration Flow per Exterior Envelope Surface Area (cfm/ft^2).') # (ft^3/min)/(ft^2) = (ft/min)
  infiltration_ip.setDefaultValue(0.05)
  args << infiltration_ip

  # make an argument for material and installation cost
  material_cost_ip = OpenStudio::Measure::OSArgument.makeDoubleArgument('material_cost_ip', true)
  material_cost_ip.setDisplayName('Increase in Material and Installation Costs for Building per Exterior Envelope Area ($/ft^2).')
  material_cost_ip.setDefaultValue(0.0)
  args << material_cost_ip

  # make an argument for o&m cost
  om_cost_ip = OpenStudio::Measure::OSArgument.makeDoubleArgument('om_cost_ip', true)
  om_cost_ip.setDisplayName('O & M Costs for Construction per Area Used ($/ft^2).')
  om_cost_ip.setDefaultValue(0.0)
  args << om_cost_ip

  # make an argument for o&m frequency
  om_frequency = OpenStudio::Measure::OSArgument.makeIntegerArgument('om_frequency', true)
  om_frequency.setDisplayName('O & M Frequency (whole years).')
  om_frequency.setDefaultValue(1)
  args << om_frequency

  return args
end

#name ⇒ Object

define the name that a user will see



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# File 'lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb', line 9

def name
  return 'Set Space Infiltration by Exterior Surface Area'
end

#neat_numbers(number, roundto = 2) ⇒ Object

short def to make numbers pretty (converts 4125001.25641 to 4,125,001.26 or 4,125,001). The definition be called through this measure



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# File 'lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb', line 71

def neat_numbers(number, roundto = 2) # round to 0 or 2)
  if roundto == 2
    number = format '%.2f', number
  else
    number = number.round
  end
  # regex to add commas
  number.to_s.reverse.gsub(/([0-9]{3}(?=([0-9])))/, '\\1,').reverse
end

#run(model, runner, user_arguments) ⇒ Object

define what happens when the measure is run



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# File 'lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb', line 45

def run(model, runner, user_arguments)
  super(model, runner, user_arguments)

  # use the built-in error checking
  if !runner.validateUserArguments(arguments(model), user_arguments)
    return false
  end

  # assign the user inputs to variables
  infiltration_ip = runner.getDoubleArgumentValue('infiltration_ip', user_arguments)
  material_cost_ip = runner.getDoubleArgumentValue('material_cost_ip', user_arguments)
  years_until_costs_start = 0 # removed user argument and set it to 0. For this measure it should always be 0
  om_cost_ip = runner.getDoubleArgumentValue('om_cost_ip', user_arguments)
  om_frequency = runner.getIntegerArgumentValue('om_frequency', user_arguments)

  # check infiltration for reasonableness
  if infiltration_ip < 0
    runner.registerError("The requested space infiltration flow rate of #{infiltration_ip} cfm/ft^2 was below the measure limit. Choose a positive number.")
    return false
  elsif infiltration_ip == 0.001 # put more thought into best warning trigger value
    runner.registerWarning("The requested space infiltration flow rate of  #{infiltration_ip} cfm/ft^2 seems abnormally low.")
  elsif infiltration_ip > 1.0 # put more thought into best warning trigger value
    runner.registerWarning("The requested space infiltration flow rate of  #{infiltration_ip} cfm/ft^2 seems abnormally high.")
  end

  # short def to make numbers pretty (converts 4125001.25641 to 4,125,001.26 or 4,125,001). The definition be called through this measure
  def neat_numbers(number, roundto = 2) # round to 0 or 2)
    if roundto == 2
      number = format '%.2f', number
    else
      number = number.round
    end
    # regex to add commas
    number.to_s.reverse.gsub(/([0-9]{3}(?=([0-9])))/, '\\1,').reverse
  end

  # helper to make it easier to do unit conversions on the fly
  def unit_helper(number, from_unit_string, to_unit_string)
    converted_number = OpenStudio.convert(OpenStudio::Quantity.new(number, OpenStudio.createUnit(from_unit_string).get), OpenStudio.createUnit(to_unit_string).get).get.value
  end

  # get space infiltration objects used in the model
  space_infiltration_objects = model.getSpaceInfiltrationDesignFlowRates

  # reporting initial condition of model
  if !space_infiltration_objects.empty?
    runner.registerInitialCondition("The initial model contained #{space_infiltration_objects.size} space infiltration objects.")
  else
    runner.registerInitialCondition('The initial model did not contain any space infiltration objects.')
  end

  # remove space infiltration objects
  number_removed = 0
  number_left = 0
  space_infiltration_objects.each do |space_infiltration_object|
    opt_space_type = space_infiltration_object.spaceType
    if opt_space_type.empty?
      space_infiltration_object.remove
      number_removed += 1
    elsif !opt_space_type.get.spaces.empty?
      space_infiltration_object.remove
      number_removed += 1
    else
      number_left += 1
    end
  end
  if number_removed > 0
    runner.registerInfo("#{number_removed} infiltration objects were removed.")
  end
  if number_left > 0
    runner.registerInfo("#{number_left} infiltration objects in unused space types were left in the model. They will not be altered.")
  end

  # if no default space type then add an empty one (to hold new space infiltration object)
  building = model.getBuilding
  if building.spaceType.empty?
    new_default = OpenStudio::Model::SpaceType.new(model)
    new_default.setName('Building Default Space Type')
    building.setSpaceType(new_default)
    runner.registerInfo("Adding a building default space type to hold space infiltration for spaces that previously didn't have a space type.")
  end

  # si units for infiltration argument
  infiltration_si = unit_helper(infiltration_ip, 'ft/min', 'm/s')

  # loop through spacetypes used in the model adding space infiltration objects
  space_types = model.getSpaceTypes
  space_types.each do |space_type|
    if !space_type.spaces.empty?
      new_space_type_infil = OpenStudio::Model::SpaceInfiltrationDesignFlowRate.new(model)
      new_space_type_infil.setFlowperExteriorSurfaceArea(infiltration_si)
      new_space_type_infil.setSpaceType(space_type)
      if new_space_type_infil.schedule.empty?
        # TODO: - check if the warning below is falsely triggering when it does not need to.
        runner.registerWarning("The new infiltration object for space type '#{space_type.name}' does not have a schedule. Assigning a default schedule set including an infiltration schedule to the space type or the building will address this.")
      end
    end
  end

  # get area of surfaces with outdoor boundary condition. Take zone multipliers into account
  surfaces = model.getSurfaces
  exterior_surface_gross_area = 0
  space_warning_issued = []

  surfaces.each do |s|
    next if s.outsideBoundaryCondition != 'Outdoors'

    # get surface area adjusting for zone multiplier
    space = s.space
    if !space.empty?
      zone = space.get.thermalZone
    end
    if !zone.empty?
      zone_multiplier = zone.get.multiplier
      if (zone_multiplier > 1) && !space_warning_issued.include?(space.get.name.to_s)
        runner.registerInfo("Space #{space.get.name} in thermal zone #{zone.get.name} has a zone multiplier of #{zone_multiplier}. Adjusting area calculations.")
        space_warning_issued << space.get.name.to_s
      end
    else
      zone_multiplier = 1 # space is not in a thermal zone
      runner.registerWarning("Space #{space.get.name} is not in a thermal zone and won't be included in in the simulation. For area calculations in this measure a zone multiplier of 1 will be assumed.")
    end
    exterior_surface_gross_area += s.grossArea * zone_multiplier
  end

  # ip exterior surface area for reporting and building lifeCycleCostObject
  exterior_surface_gross_area_ip = unit_helper(exterior_surface_gross_area, 'm^2', 'ft^2')

  # only add LifeCyCyleCostItem if the user entered some non 0 cost values
  if (material_cost_ip != 0) || (om_cost_ip != 0)
    material_cost_si = unit_helper(material_cost_ip, '1/ft^2', '1/m^2')
    om_cost_si = unit_helper(om_cost_ip, '1/ft^2', '1/m^2')
    lcc_mat = OpenStudio::Model::LifeCycleCost.createLifeCycleCost('LCC_Mat - Cost to Adjust Infiltration', building, exterior_surface_gross_area * material_cost_si, 'CostPerEach', 'Construction', 0, years_until_costs_start) # 0 for expected life will result infinite expected life
    lcc_om = OpenStudio::Model::LifeCycleCost.createLifeCycleCost('LCC_OM - Cost to Adjust Infiltration', building, exterior_surface_gross_area * om_cost_si, 'CostPerEach', 'Maintenance', om_frequency, years_until_costs_start) # o&m costs start after at sane time that material and installation costs occur
    runner.registerInfo("Costs related to the change in infiltration are attached to the building object. Any subsequent measures that may affect infiltration won't affect these costs.")
  else
    runner.registerInfo('Cost arguments were not provided, no cost objects were added to the model.')
  end

  # reporting final condition of model
  if !lcc_mat.nil?
    cost_per_area_ip = lcc_mat.get.totalCost / exterior_surface_gross_area_ip
  else
    cost_per_area_ip = 0
  end

  runner.registerFinalCondition("The final model has an infiltration rate of #{neat_numbers(infiltration_ip)} (cfm/ft^2). The material and installation cost increase resulting from this measure is $#{neat_numbers(cost_per_area_ip)} ($/ft^2) over #{neat_numbers(exterior_surface_gross_area_ip, 0)} (ft^2) of exterior envelope.")

  return true
end

#unit_helper(number, from_unit_string, to_unit_string) ⇒ Object

helper to make it easier to do unit conversions on the fly



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# File 'lib/measures/SetSpaceInfiltrationByExteriorSurfaceArea/measure.rb', line 82

def unit_helper(number, from_unit_string, to_unit_string)
  converted_number = OpenStudio.convert(OpenStudio::Quantity.new(number, OpenStudio.createUnit(from_unit_string).get), OpenStudio.createUnit(to_unit_string).get).get.value
end