class OpenStudio::Model::AirTerminalSingleDuctVAVReheat # Set the minimum damper position based on OA # rate of the space and the building vintage. # Zones with low OA per area get lower initial guesses. # Final position will be adjusted upward # as necessary by Standards.AirLoopHVAC.adjust_minimum_vav_damper_positions # @param building_vintage [String] the building vintage # @param zone_oa_per_area [Double] the zone outdoor air per area, m^3/s # @param has_ddc [Bool] whether or not there is DDC control of the VAV terminal # @return [Bool] returns true if successful, false if not # @todo remove exception where older vintages don't have minimum positions adjusted. def set_minimum_damper_position(building_vintage, zone_oa_per_area, has_ddc = true) # Minimum damper position is based on prototype # assumptions, which are not clearly documented. min_damper_position = nil case building_vintage when 'DOE Ref Pre-1980', 'DOE Ref 1980-2004', '90.1-2004' min_damper_position = 0.3 when '90.1-2007' min_damper_position = 0.3 when '90.1-2010', '90.1-2013' if has_ddc min_damper_position = 0.2 else min_damper_position = 0.3 end end # TODO remove the template conditional; doesn't make sense # 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 # High OA zones self.setConstantMinimumAirFlowFraction(0.7) else # Low OA zones self.setConstantMinimumAirFlowFraction(min_damper_position) end return true end end