Minimum zone ventilation efficiency

[lymereJ]

Enhancement Request

The SDK allows users to set/get the zone air distribution effectiveness in heating/cooling mode via DesignSpecificationZoneAirDistribution and SizingZone but not the minimum zone ventilation efficiency, which is a valid input in EnergyPlus. It would great if the later could be added.

[jmarrec]

Confirmed it's missing in OpenStudio, and easy to add.

OS:DesignSpecification:ZoneAirDistribution,
   [...]
   N3;  \field Zone Secondary Recirculation Fraction
        \type real
        \default 0.0
        \minimum 0.0
        \units dimensionless

replace with

OS:DesignSpecification:ZoneAirDistribution,
   [...]
   N3,  \field Zone Secondary Recirculation Fraction
        \type real
        \default 0.0
        \minimum 0.0
        \units dimensionless
   N4;  \field Minimum Zone Ventilation Efficiency
        \type real
        \default 0.0
        \minimum 0.0
        \maximum 1.0
        \units dimensionless

[jmarrec]

Hmmm, actually, I seems that while the object appears to be wrapped in the model API (DesignSpecificationZoneAirDistribution has a class, and registered constructors etc), it's not being used during forward translation at all. Instead the OS:Sizing:Zone is the one that adds some of the fields directly.

OpenStudio/src/model/Model.cpp

Line 2842 in 92c9f11

REGISTER_CONSTRUCTOR(DesignSpecificationZoneAirDistribution);

OpenStudio/src/model/DesignSpecificationZoneAirDistribution.hpp

Line 50 in 92c9f11

class MODEL_API DesignSpecificationZoneAirDistribution : public ModelObject {

It's not SWIG'ed either.

[lymereJ]

Could this be included in the next OpenStudio release?

[tijcolem]

@jmarrec Can we get this in for 3.0.0? Run regression tests to make sure no major changes?

[jmarrec]

Its possible, but not as straightforward as I had thought initially since the existing class is actually not used. Requires modifying the model API to make use of it, or strapping the new field onto the SizingZone object like it is now (less work for sure).

@kbenne thoughts? I would assume put it on OS:Sizing:Zone?

[tijcolem]

closed and merged in #3915