[EnergyPlus_Support] Heat Transfer Through Internal Windows

["dan_grunbaum" <dan_grunbaum@xxxxxxxxx>]

Hi there,

We are simulating a ventilated double skin facade by creating a cavity zone 200 mm deep adjacent to the occupied  perimeter) zone. The external surface of the cavity is glazed and the internal surface separating the cavity from the perimeter zone is also glazed and there is an operable blind within the cavity. 

We are attempting to do a heat balance to ensure we understand the benefit of ventilating the cavity with external air. We have started looking at the situation where there is no blind within the cavity. To determine the heat flow from the cavity zone to the perimeter zone we have been looking at the "Window Heat Gain" variable for the internal glazed surface separating the two zones.  This value appears very low when compared to the sum of "Beam Solar Transmitted through Interior Window", "Zone Diff Solar from Exterior Windows", and "Surface Int Convection Heat Rate" for the internal window. Does the "Window Heat Gain" variable represent the total heat gain through internal windows or are we misinterpreting? 

In addition there does not seem to be variables for the long wave radiant transfer through the internal glazed surface or the conductive gain through the frame. There are the "Window Net Infrared Heat Gain/Loss from Glazing to Zone" and the "Window Heat Gain from Frame and Divider to Zone" variables for the external glazing, however there do not appear to be corresponding values for internal glazed elements. Is there a way of establishing what these variables are for the internal glazing?

Regards,

Dan




------------------------------------

Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

The primary EnergyPlus web site is found at:
http://www.energyplus.gov

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/join
    (Yahoo! ID required)

<*> To change settings via email:
    EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx

<*> To unsubscribe from this group, send an email to:
    EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/