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Window Downdraft
Use this component to compute the floor-level downdraft air temperature and velocity at a given set of points that are located close to a cold surface such as a window. The draft conditions produced by this model are assumed to be 10 cm off of the floor.
The model used in this component comes from physical measurements of window downdraft that were further validated using several CFD experiments. Ther are published in these papers:
Heiselberg, P. (1994). “Draft Risk from Cold Vertical Surfaces.” Building and Environment, 29: 297-301.
Manz, H. and Frank, T. (2003). "Analysis of Thermal Comfort near Cold Vertical Surfaces by Means of Computational Fluid Dynamics." Indoor Built Environment. 13: 233-242.
Inputs
| Name | ID | Description | Type |
|---|---|---|---|
| Test Pts | _testPts | The test points at which downdraft conditions will be evaluated. | Goo |
| Window Srfs | _windowSrfs | Breps or Surfaces representing the window surfaces off of which downdraft flows. | Goo |
| Win Srf Temp | _winSrfTemp | A number representing the surface temperature of the windows in degrees Celcius. | Goo |
| Air Temp | _airTemp | A number representing the air temperature of the room in degrees Celcius. | Goo |
| Default Veloc | defaultVeloc_ | A number in m/s that represents the speed of the air that is not in the downdraft. The default is set to 0.05 m/s. | Goo |
| Run It | _runIt | Set to 'True' to run the component and claculate downdraft conditions. | Goo |
Outputs
| Name | ID | Description | Type |
|---|---|---|---|
| Draft Air Temp | draftAirTemp | Script output PPD. | Goo |
| Draft Air Veloc | draftAirVeloc | Script variable downDraft | Goo |
| ---------- | ---------- | Script variable downDraft | Goo |
| Air Flow Planes | airFlowPlanes | Script variable downDraft | Goo |
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