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How to input Glass spectral and Incident Angle Transmittance and reflectance

asked 2021-09-30 03:01:50 -0500

it's avatar

updated 2022-02-06 12:15:31 -0500

In EnergyPlus, WindowMaterial: Glazing module has three parts to input Glass spectral and Incident Angle transmittancee, front reflectance, and back reflectance. Though, I cannnot find out a table to define such values. Does anyone know how to define and input values?

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answered 2021-09-30 03:23:35 -0500

Petros Dalavouras's avatar

You can use WINDOW from LBNL to model your windows and then export an .idf file with all the values you need both for average and spectral data

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Thank you for your comments. When exported from WINDOW, the bottom three cells in WindowMaterial: Glazing are blank. This means WINDOW exported data has no information for the three cells. I am wondering to define these three cells.

it's avatar it  ( 2021-09-30 04:07:49 -0500 )edit

I'm sorry I didn't grasp your question at first. So you need to use Optical Data Type = SpectralAndAngle. In this case I'm afraid that I can only point you at the example file "SpectralAngularOpticalProperties_TableData" which in the description says: "This file does the basic test of window properties as a function of wavelength and incident angle based on Winklemann approach. Table data are used to input optical properties. Linear interpolation is performed to calculate optical properties with a given incident angle." My take from this is that you should probably calculate the angular

Petros Dalavouras's avatar Petros Dalavouras  ( 2021-09-30 11:22:35 -0500 )edit

properties of the spectral data you obtained from WINDOW so as to create the table. In the Engineering Reference you can find this method of calculation.

Petros Dalavouras's avatar Petros Dalavouras  ( 2021-09-30 11:27:35 -0500 )edit

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Asked: 2021-09-30 03:01:50 -0500

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Last updated: Sep 30 '21