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NREL / EnergyPlus

EnergyPlus™ is a whole building energy simulation program that engineers, architects, and researchers use to model both energy consumption and water use in buildings.
https://energyplus.net
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Update DCV documentation to make it clear that VRP is not CO2 based #4186

Closed JasonGlazer closed 9 years ago

JasonGlazer commented 10 years ago

The IOref says

"EnergyPlus can model CO2-based DCV by the ventilation rate procedure (VRP) defined in ASHRAE Standard 62.1-2007/2010 for single and multiple path systems, and the indoor air quality procedure (IAQP) defined in Standard 62."

This implies that VRP is based on tracking CO2 but I do not believe it is.

lgu1234 commented 10 years ago

If I serached "EnergyPlus can model CO2-based DCV", I could not find the same paragraph. If I searched "CO2-based DCV", the following section is shown in either Ver. 8.1 or the latest IO Ref:

Field: System Outdoor Air Method The method used to calculate the system minimum outdoor air flow. Several choices are allowed: ZoneSum, VentilationRateProcedure, IndoorAirQualityProcedure, ProportionalControl, and IndoorAirQualityProcedureGenericContaminant. ZoneSum sums the outdoor air flows across all zones served by the system. VentilationRateProcedure (VRP) uses the multi-zone equations defined in 62.1-2007 to calculate the system outdoor air flow. VRP considers zone air distribution effectiveness and zone diversification of outdoor air fractions. IndoorAirQualityProcedure (IAQP) is the other procedure defined in ASHRAE Standard 62.1-2007 for calculate the amount of outdoor air necessary to maintain the levels of indoor air carbon dioxide at or below the setpoint defined in the ZoneControl:ContaminantController object. Appendix A of the ASHRAE 62.1-2010 user’s manual discusses another method for implementing CO2-based DCV in a single zone system. This method (Proportional Control) calculates the required outdoor air flow rate which varies in proportion to the percentage of the CO2 signal range. The IndoorAirQualityProcedure-GenericContaminant method calculates the amount of outdoor air necessary to maintain the levels of indoor air generic contaminant at or below the setpoint defined in the ZoneControl:ContaminantController object.

Could you let me know which version you referred to?

JasonGlazer commented 10 years ago

Sorry, it is in the EngineeringReference.pdf page 825 (pdf 852)

lgu1234 commented 10 years ago

My guess is that one of VRP is CO2-based DCV. Tianzhen may have better explanation.

JasonGlazer commented 10 years ago

Tianzhen @hongtz68 can you take a look

lgu1234 commented 9 years ago

The Eng. Ref was revised and uploaded. @JasonGlazer accepted the revision. This issue is closed.

lgu1234 commented 9 years ago

@JasonGlazer Could you close this issue?