From 1b631e4a24481ea908177a951fb787e2c4ce2b42 Mon Sep 17 00:00:00 2001 From: Jason DeGraw Date: Sat, 3 Apr 2021 14:25:06 -0400 Subject: [PATCH] Create NFP-AFN-Linkage-Control.md --- design/FY2021/NFP-AFN-Linkage-Control.md | 144 +++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 design/FY2021/NFP-AFN-Linkage-Control.md diff --git a/design/FY2021/NFP-AFN-Linkage-Control.md b/design/FY2021/NFP-AFN-Linkage-Control.md new file mode 100644 index 00000000000..c7a952be03d --- /dev/null +++ b/design/FY2021/NFP-AFN-Linkage-Control.md @@ -0,0 +1,144 @@ +# Improved AirflowNetwork Flow Linkage Controls # + +Jason DeGraw, Prateek Shrestha + +Oak Ridge National Laboratory + +Original Date: March 31, 2021 + +## Justification for New Feature ## +AirflowNetwork does not currently distinguish between a control factor and a multiplier for flow linkages. One input signal is allowed that is limited to [0,1], +which precludes many use cases, including variable crack lengths, per area leakage elements, and multiple windows represented by a single path. Futhermore, it +is no longer possible to modify the IDD to allow for other uses. + +## Overview ## +A multiplier factor enables an independent control of the size of a flow linkage without having to adjust the flow characteristics of the linkage component(s). +Once the user defines such a linkage characteristics, changing merely the multiplier in one location will enable the user to change the number of leakage path +openings connecting different nodes and can make the model set-up task faster and easier for the user. + +## Approach ## +Previous work has added the necessary parameters to the function signatures to allow separate control and multiplier inputs. + +* Add the necessary input fields +* Separate the usage of the two values internal to AirflowNetwork +* Add schedulability and EMS control (budget permitting) +* Create unit tests and documentation + +## Testing/Validation/Data Sources ## +Unit tests will be implemented to ensure numerical values are calculated properly. + +## Input Output Reference Documentation +Additions will be made to the Input Output Reference for the multiplier associated with the flow linkage. + +## Input Description ## +The current distribution linkage object will be modified to include the multiplier, control, and control schedule fields: + +``` +AirflowNetwork:Distribution:Linkage, + \min-fields 4 + \memo This object defines the connection between two nodes and a component. + A1 , \field Name + \required-field + \type alpha + \note Enter a unique name for this object. + A2 , \field Node 1 Name + \required-field + \type object-list + \object-list AirflowNetworkNodeAndZoneNames + \note Enter the name of zone or AirflowNetwork Node. + A3 , \field Node 2 Name + \required-field + \type object-list + \object-list AirflowNetworkNodeAndZoneNames + \note Enter the name of zone or AirflowNetwork Node. + A4 , \field Component Name + \required-field + \type object-list + \object-list AirflowNetworkComponentNames + \object-list FansCVandOnOffandVAV + \object-list AFNCoilNames + \object-list AFNHeatExchangerNames + \object-list AFNTerminalUnitNames + \note Enter the name of an AirflowNetwork component. A component is one of the + \note following AirflowNetwork:Distribution:Component objects: Leak, LeakageRatio, + \note Duct, ConstantVolumeFan, Coil, TerminalUnit, ConstantPressureDrop, or HeatExchanger. + A5 , \field Thermal Zone Name + \type object-list + \object-list ZoneNames + \note Only used if component = AirflowNetwork:Distribution:Component:Duct + \note The zone name is where AirflowNetwork:Distribution:Component:Duct is exposed. +N1 , \field Multiplier + \type real + \note +N2 , \field Control Value + \type real + \note +A6 ; \field Control Schedule Name + \type object-list + \object-list ScheduleNames +``` + +A new object will be added for multizone linkages: + +``` +AirflowNetwork:MultiZone:Linkage, + \min-fields 4 + \memo This object defines the connection between two nodes and a component. + A1 , \field Name + \required-field + \type alpha + \note Enter a unique name for this object. + A2 , \field Node 1 Name + \required-field + \type object-list + \object-list AirflowNetworkNodeAndZoneNames + \note Enter the name of zone or AirflowNetwork Node. + A3 , \field Node 2 Name + \required-field + \type object-list + \object-list AirflowNetworkNodeAndZoneNames + \note Enter the name of zone or AirflowNetwork Node. + A2 , \field Surface Name + \required-field + \type object-list + \object-list SurfAndSubSurfNames + \note Enter the name of a heat transfer surface. + A3 , \field Leakage Component Name + \required-field + \type object-list + \object-list SurfaceAirflowLeakageNames + \note Enter the name of an Airflow Network leakage component. A leakage component is + \note one of the following AirflowNetwork:Multizone objects: + \note AirflowNetwork:MultiZone:Component:DetailedOpening, + \note AirflowNetwork:MultiZone:Component:SimpleOpening, + \note AirflowNetwork:MultiZone:Surface:Crack, + \note AirflowNetwork:MultiZone:Surface:EffectiveLeakageArea, + \note AirflowNetwork:MultiZone:Component:HorizontalOpening, or + \note AirflowNetwork:MultiZone:Component:ZoneExhaustFan. + \note When the zone exhaust fan name is entered, any surface control fields below A3 are + \note ignored when the zone exhaust fan turns on. +N1 , \field Multiplier + \type real + \note +N2 , \field Control Value + \type real + \note +A4 ; \field Control Schedule Name + \type object-list + \object-list ScheduleNames +``` + +The planned modifications do not include the `AirflowNetwork:MultiZone:Surface` object. It will continue to work as-is. The intrazonal links object may also need to be +modified, this will be discussed with the development team. + +## Outputs Description ## +No new output variables will be implemented with this work as existing variables are sufficient to gather relevant airflow information. + +## Engineering Reference ## +N/A + +## Example File and Transition Changes ## +Suitable example file will be generated. Since the multiplier will be incorporated within existing framework of flow linages, no transition rules are anticipated. + +## References ## +N/A