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# Schedule/Actuate Adjacent Air or Surface Temperature of a Window

I am attempting to add an air temperature adjacent to a window or surface temperature of a window in EnergyPlus. This would act as if it were a boundary condition and would be controlled by a schedule or an actuator.

I tried the SurfaceProperty:OtherSideCoefficients object but found that it does not work on walls with windows.

Is there a component I can use or an actuator I could apply to override the surface temperature of a specific window in a model?

While on the subject is there a component or actuator I can use to control the direct and diffuse radiation incident on a glazed surface.

Thank you for your time,

Justin

UPDATE ON October 18, 2016Building on @Archmage's answer and a relevant answer by @Ivan Korolija in another question found here: https://unmethours.com/question/20541.... I was able to solve the problem brought up in this question.

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There is an EMS actuator called "Other Side Boundary Condition" with the control type "Convection Bulk Air Temperature" that is available for each surface.

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Hi @Archmage, thank you for your response. Correct me if I'm work, but what your saying is that although Other Side Coefficient cannot be directly applied to a window, I can however use an EMS Actuator to apply the other side boundary condition after the fact? If that is the case, do you know any examples I could use?

( 2016-09-19 13:48:25 -0600 )edit

That EMS actuator would be used with the usual "Outdoors" boundary condition setting. It overrides the outdoor air temperature that would usually come from the weather description. I do not know of any examples.

( 2016-09-19 14:52:55 -0600 )edit

Thank you again for your response. Is there a way to change the "Outdoors" condition for a specific surface only? In other words, I would like to apply it to just one zone or window unit.

( 2016-09-19 15:14:20 -0600 )edit

Yes, that is what I meant by the actuator being "available for each surface" The window subsurface will inherit the Outdoors boundary condition from the surrounding base surface. I haven't actually used this EMS actuator for a window but I think it should work.

( 2016-09-19 15:58:48 -0600 )edit

While you are able to set the Outside Boundary Condition Object to the name of the SurfaceProperties:OtherSideCoeffients object it does not applies to windows or glassdoors.

The rules are complicated, from the EnergyPlus InputOutputReference 8.5 for the FenestrationSurface:Detailed object:

If the base surface has Outside Boundary Condition = Surface or OtherSideCoefficients, then this field must also be specified for the subsurface. Otherwise, it can be left blank.

If the base surface has Outside Boundary Condition = Zone, then this surface retains that characteristic and uses the same zone of the base surface. It can be entered here for clarity or it can be left blank.

If Outside Boundary Condition for the base surface is Surface, this field should specify the subsurface in the opposing zone that is the counterpart to this subsurface. The constructions of the subsurface and opposing subsurface must match, except that, for multi-layer constructions, the layer order of the opposing subsurface’s construction must be the reverse of that of the subsurface.

If Outside Boundary Condition for the base surface is OtherSideCoefficients, this field could specify the set of SurfaceProperty:OtherSideCoefficients for this subsurface. If this is left blank, then the Other Side Coefficients of the base surface will be used for this subsurface. Windows and GlassDoors are not allowed to have Other Side Coefficients.

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Hi @JasonGlazer, Thank you for your reply. So based on the last line of your quote, Other Side Coefficients cannot be applied directly to Windows, is that correct? Even if the Other Side Coefficient is applied directly to the window as a subsurface boundary condition?

( 2016-09-19 13:32:47 -0600 )edit

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Asked: 2016-09-16 17:06:50 -0600

Seen: 134 times

Last updated: Oct 19 '16