class CBEST242008
This class holds methods that apply CBES
T24 2008 to a given model. @ref [References::CBES]
Attributes
Public Class Methods
CBES::new
# File lib/openstudio-standards/standards/cbes/cbes_t24_2008/cbes_t24_2008.rb, line 7 def initialize super() @template = 'CBES T24 2008' load_standards_database end
Public Instance Methods
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/cbes/cbes_t24_2008/cbes_t24_2008.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
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/cbes/cbes_t24_2008/cbes_t24_2008.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
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/cbes/cbes_t24_2008/cbes_t24_2008.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
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
CBES#load_standards_database
# File lib/openstudio-standards/standards/cbes/cbes_t24_2008/cbes_t24_2008.rb, line 17 def load_standards_database(data_directories = []) super([__dir__] + data_directories) end
Baseline infiltration rate
@return [Double] the baseline infiltration rate, in cfm/ft^2 exterior above grade wall area at 75 Pa
# File lib/openstudio-standards/standards/cbes/cbes_t24_2008/cbes_t24_2008.Space.rb, line 7 def space_infiltration_rate_75_pa(space = nil) basic_infil_rate_cfm_per_ft2 = 0.5 return basic_infil_rate_cfm_per_ft2 end