Energy Conservation Measure
Supply Air Duct Leakages
Name
supply_air_duct_leakages
Display Name
Supply Air Duct Leakages
Type
UID
8d568a70-080d-4f27-97f5-5210ff639652
Version ID
6cf91abd-1309-4e3d-a67e-c082145950d8
Class Name
SupplyAirDuctLeakages
Version Modified
20180828T211346Z
Schema Version
3.0
Attributes
| Measure Type | EnergyPlusMeasure |
| Intended Software Tool | OpenStudio Application |
| Intended Software Tool | Parametric Analysis Tool |
| Intended Software Tool | Analysis Spreadsheet |
Details
| Description | Duct leakage can be caused by torn or missing external duct wrap, poor workmanship around duct takeoffs and fittings, disconnected ducts, improperly installed duct mastic, and temperature and pressure cycling. Conditioned air leaking to an unconditioned space in buildings increases the equipment heating or cooling demand and can increase fan power for variable air volume systems. This fault is categorized as a fault that occur in the ventilation system (duct) during the operation stage. This fault measure is based on a physical model where certain parameter(s) is changed in EnergyPlus to mimic the faulted operation; thus simulates supply air leakage by modifying the ZoneHVAC:AirDistributionUnit object in EnergyPlus. The fault intensity (F) is defined as the ratio of the leakage flow relative to supply flow. This measure was authored by Herrick Laboratory researchers at Purdue University in collaboration with staff from the National Renewable Energy Laboratory. For assistance using this measure please post to https://unmethours.com/questions/ | |
| Modeler Description | Two user inputs are required to simulate the fault. The ZoneHVAC:AirDistributionUnit object has two leakage options (upstream and downstream leakages) available. For supply duct leakage, the leakage ratio (leakage flow relative to supply flow) is applied to the downstream leakage parameter and the upstream leakage parameter is replaced with zero in the object. To use this Measure, choose the AirTerminal object to be faulted and a ratio of leakage flow rate to the airflow directed to the zone upstream to the leak. Equation, r_(leak,dnst,F) = 1 - ( 1 - r_(leak,dnst) ) * ( 1 - F ) provides an expression for the downstream leakage ratio (r_(leak,dnst,F)) under faulty conditions in terms of a normal leakage ratio (r_(leak,dnst)) and a fault intensity (F) defined as the ratio of the leakage flow relative to supply flow. | |
Files
| frp_baseline_generic_sch.osm |
| measure_test.rb |
| measure.rb OpenStudio 2.4.0 Min Compatible Version: 2.4.0 Max Compatible Version: 2.4.1 |
| LICENSE.txt |
Content visibility
Use group defaults
Measure Arguments
| Name | Display Name | Short Name | Description | Units | Type | Required | Model Dependent | Default Value | Choices | Min Value | Max Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| airterminal_choice | Select the name of the faulted AirTerminal object | - | - | - | Choice | true | false | - | - | - | - |
| leak_ratio | Ratio of leak airflow between 0 and 0.3. | - | - | - | Double | false | false | 0.1 | - | - | - |