Class: OpenStudio::Model::ChillerElectricEIR

Inherits:
Object
  • Object
show all
Defined in:
lib/openstudio-standards/standards/Standards.ChillerElectricEIR.rb,
lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb

Overview

open the class to add methods to return sizing values

Instance Method Summary collapse

Instance Method Details

#apply_efficiency_and_curves(template, clg_tower_objs) ⇒ Bool

Applies the standard efficiency ratings and typical performance curves to this object.

Parameters:

  • template (String) —

    valid choices: ‘DOE Ref Pre-1980’, ‘DOE Ref 1980-2004’, ‘90.1-2004’, ‘90.1-2007’, ‘90.1-2010’, ‘90.1-2013’

  • standards (Hash) —

    the OpenStudio_Standards spreadsheet in hash format

Returns:

  • (Bool) —

    true if successful, false if not



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# File 'lib/openstudio-standards/standards/Standards.ChillerElectricEIR.rb', line 102

def apply_efficiency_and_curves(template, clg_tower_objs)
  chillers = $os_standards['chillers']

  # Define the criteria to find the chiller properties
  # in the hvac standards data set.
  search_criteria = find_search_criteria(template)
  cooling_type = search_criteria['cooling_type']
  condenser_type = search_criteria['condenser_type']
  compressor_type = search_criteria['compressor_type']

  # Get the chiller capacity
  capacity_w = find_capacity

  # NECB 2011 requires that all chillers be modulating down to 25% of their capacity
  if template == 'NECB 2011'
    setChillerFlowMode('LeavingSetpointModulated')
    setMinimumPartLoadRatio(0.25)
    setMinimumUnloadingRatio(0.25)
    if (capacity_w / 1000.0) < 2100.0
      if self.name.to_s.include? 'Primary Chiller'
        chiller_capacity = capacity_w
      elsif self.name.to_s.include? 'Secondary Chiller'
        chiller_capacity = 0.001
      end
    else
      chiller_capacity = capacity_w / 2.0
    end
    setReferenceCapacity(chiller_capacity)
  end # NECB 2011

  # Convert capacity to tons
  capacity_tons = if template == 'NECB 2011'
                    OpenStudio.convert(chiller_capacity, 'W', 'ton').get
                  else
                    OpenStudio.convert(capacity_w, 'W', 'ton').get
                  end

  # Get the chiller properties
  chlr_props = model.find_object(chillers, search_criteria, capacity_tons, Date.today)
  unless chlr_props
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{self.name}, cannot find chiller properties, cannot apply standard efficiencies or curves.")
    successfully_set_all_properties = false
    return successfully_set_all_properties
  end

  # Make the CAPFT curve
  cool_cap_ft = model.add_curve(chlr_props['capft'])
  if cool_cap_ft
    setCoolingCapacityFunctionOfTemperature(cool_cap_ft)
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{self.name}, cannot find cool_cap_ft curve, will not be set.")
    successfully_set_all_properties = false
  end

  # Make the EIRFT curve
  cool_eir_ft = model.add_curve(chlr_props['eirft'])
  if cool_eir_ft
    setElectricInputToCoolingOutputRatioFunctionOfTemperature(cool_eir_ft)
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{self.name}, cannot find cool_eir_ft curve, will not be set.")
    successfully_set_all_properties = false
  end

  # Make the EIRFPLR curve
  # which may be either a CurveBicubic or a CurveQuadratic based on chiller type
  cool_plf_fplr = model.add_curve(chlr_props['eirfplr'])
  if cool_plf_fplr
    setElectricInputToCoolingOutputRatioFunctionOfPLR(cool_plf_fplr)
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{self.name}, cannot find cool_plf_fplr curve, will not be set.")
    successfully_set_all_properties = false
  end

  # Set the efficiency value
  kw_per_ton = nil
  cop = nil
  if chlr_props['minimum_full_load_efficiency']
    kw_per_ton = chlr_props['minimum_full_load_efficiency']
    cop = kw_per_ton_to_cop(kw_per_ton)
    setReferenceCOP(cop)
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{self.name}, cannot find minimum full load efficiency, will not be set.")
    successfully_set_all_properties = false
  end

  # Set cooling tower properties for NECB 2011 now that the new COP of the chiller is set
  if template == 'NECB 2011'
    if self.name.to_s.include? 'Primary Chiller'
      # Single speed tower model assumes 25% extra for compressor power
      tower_cap = capacity_w * (1.0 + 1.0 / referenceCOP)
      if (tower_cap / 1000.0) < 1750
        clg_tower_objs[0].setNumberofCells(1)
      else
        clg_tower_objs[0].setNumberofCells((tower_cap / (1000 * 1750) + 0.5).round)
      end
      clg_tower_objs[0].setFanPoweratDesignAirFlowRate(0.015 * tower_cap)
    end
  end

  # Append the name with size and kw/ton
  setName("#{name} #{capacity_tons.round}tons #{kw_per_ton.round(1)}kW/ton")
  OpenStudio.logFree(OpenStudio::Info, 'openstudio.model.ChillerElectricEIR', "For #{template}: #{self.name}: #{cooling_type} #{condenser_type} #{compressor_type} Capacity = #{capacity_tons.round}tons; COP = #{cop.round(1)} (#{kw_per_ton.round(1)}kW/ton)")

  return successfully_set_all_properties
end

#applySizingValues ⇒ Object

Takes the values calculated by the EnergyPlus sizing routines and puts them into this object model in place of the autosized fields. Must have previously completed a run with sql output for this to work.



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# File 'lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb', line 13

def applySizingValues

  reference_chilled_water_flow_rate = self.autosizedReferenceChilledWaterFlowRate
  if reference_chilled_water_flow_rate.is_initialized
    self.setReferenceChilledWaterFlowRate(reference_chilled_water_flow_rate.get) 
  end

  reference_capacity = self.autosizedReferenceCapacity
  if reference_capacity.is_initialized
    self.setReferenceCapacity(reference_capacity.get) 
  end

  # Only try to find the condenser water flow rate if this chiller
  # is a water cooled chiller connected to a condenser loop.
  if self.secondaryPlantLoop.is_initialized
    reference_condenser_fluid_flow_rate = self.autosizedReferenceCondenserFluidFlowRate
    if reference_condenser_fluid_flow_rate.is_initialized
      self.setReferenceCondenserFluidFlowRate(reference_condenser_fluid_flow_rate.get) 
    end
  end
  
end

#autosize ⇒ Object

Sets all auto-sizeable fields to autosize



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# File 'lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb', line 6

def autosize
  OpenStudio::logFree(OpenStudio::Warn, "openstudio.sizing.ChillerElectricEIR", ".autosize not yet implemented for #{self.iddObject.type.valueDescription}.")
end

#autosizedReferenceCapacity ⇒ Object

returns the autosized reference capacity as an optional double



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# File 'lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb', line 44

def autosizedReferenceCapacity

  return self.model.getAutosizedValue(self, 'Design Size Reference Capacity', 'W')

end

#autosizedReferenceChilledWaterFlowRate ⇒ Object

returns the autosized chilled water flow rate as an optional double



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# File 'lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb', line 37

def autosizedReferenceChilledWaterFlowRate

  return self.model.getAutosizedValue(self, 'Design Size Reference Chilled Water Flow Rate', 'm3/s')
  
end

#autosizedReferenceCondenserFluidFlowRate ⇒ Object

returns the autosized reference condenser fluid flow rate as an optional double



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# File 'lib/openstudio-standards/hvac_sizing/Siz.ChillerElectricEIR.rb', line 51

def autosizedReferenceCondenserFluidFlowRate

  return self.model.getAutosizedValue(self, 'User-Specified Reference Condenser Water Flow Rate', 'm3/s')
  
end

#find_capacity ⇒ Double

Finds capacity in W

Returns:

  • (Double) —

    capacity in W to be used for find object



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# File 'lib/openstudio-standards/standards/Standards.ChillerElectricEIR.rb', line 58

def find_capacity
  capacity_w = nil
  if referenceCapacity.is_initialized
    capacity_w = referenceCapacity.get
  elsif autosizedReferenceCapacity.is_initialized
    capacity_w = autosizedReferenceCapacity.get
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{name} capacity is not available, cannot apply efficiency standard.")
    successfully_set_all_properties = false
    return successfully_set_all_properties
  end

  return capacity_w
end

#find_search_criteria(template) ⇒ hash

Finds the search criteria

Parameters:

  • template (String) —

    valid choices: ‘DOE Ref Pre-1980’, ‘DOE Ref 1980-2004’, ‘90.1-2004’, ‘90.1-2007’, ‘90.1-2010’, ‘90.1-2013’

Returns:

  • (hash) —

    has for search criteria to be used for find object



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

def find_search_criteria(template)
  search_criteria = {}
  search_criteria['template'] = template

  # Determine if WaterCooled or AirCooled by
  # checking if the chiller is connected to a condenser
  # water loop or not.
  cooling_type = 'AirCooled'
  if secondaryPlantLoop.is_initialized
    cooling_type = 'WaterCooled'
  end

  search_criteria['cooling_type'] = cooling_type

  # TODO: Standards replace this with a mechanism to store this
  # data in the chiller object itself.
  # For now, retrieve the condenser type from the name
  name = self.name.get
  condenser_type = nil
  compressor_type = nil
  if cooling_type == 'AirCooled'
    if name.include?('WithCondenser')
      condenser_type = 'WithCondenser'
    elsif name.include?('WithoutCondenser')
      condenser_type = 'WithoutCondenser'
    end
  elsif cooling_type == 'WaterCooled'
    if name.include?('Reciprocating')
      compressor_type = 'Reciprocating'
    elsif name.include?('Rotary Screw')
      compressor_type = 'Rotary Screw'
    elsif name.include?('Scroll')
      compressor_type = 'Scroll'
    elsif name.include?('Centrifugal')
      compressor_type = 'Centrifugal'
    end
  end
  unless condenser_type.nil?
    search_criteria['condenser_type'] = condenser_type
  end
  unless compressor_type.nil?
    search_criteria['compressor_type'] = compressor_type
  end

  return search_criteria
end

#standard_minimum_full_load_efficiency(template) ⇒ Double

Finds lookup object in standards and return full load efficiency

Parameters:

  • template (String) —

    valid choices: ‘DOE Ref Pre-1980’, ‘DOE Ref 1980-2004’, ‘90.1-2004’, ‘90.1-2007’, ‘90.1-2010’, ‘90.1-2013’

  • standards (Hash) —

    the OpenStudio_Standards spreadsheet in hash format

Returns:

  • (Double) —

    full load efficiency (COP)



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# File 'lib/openstudio-standards/standards/Standards.ChillerElectricEIR.rb', line 78

def standard_minimum_full_load_efficiency(template)
  # Get the chiller properties
  search_criteria = find_search_criteria(template)
  capacity_tons = OpenStudio.convert(find_capacity, 'W', 'ton').get 
  chlr_props = model.find_object($os_standards['chillers'], search_criteria, capacity_tons, Date.today)

  # lookup the efficiency value
  kw_per_ton = nil
  cop = nil
  if chlr_props['minimum_full_load_efficiency']
    kw_per_ton = chlr_props['minimum_full_load_efficiency']
    cop = kw_per_ton_to_cop(kw_per_ton)
  else
    OpenStudio.logFree(OpenStudio::Warn, 'openstudio.standards.ChillerElectricEIR', "For #{name}, cannot find minimum full load efficiency.")
  end

  return cop
end