[Equest-users] =?gbk?q?shading_schedules__=A3=BF?=

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hello everyone!
Can anybody tell me about the shading schedules? I just dont understand its meaning?
when I creat shading schedule,what value should I input? shading coefficient or solar gain ?
ANd who can explain the "solar gain" for me ?
3Q

=?GBK?B?wt7D97jV?='s picture
Joined: 2011-09-30
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Hi 3Q--read the attached DOE-2 document look under page 40 or 47 (I can't
remember). If you look for "Building-Shade" then you should be able to
learn about the shade schedules you are asking about.

Cheers,
Pasha

2011/9/14 ???

Pasha Korber-Gonzalez's picture
Joined: 2011-09-30
Reputation: 600

Another general tip/reminder: first thing you should do after encountering an input field you are uncertain of is to right-click the field to check whether there is a corresponding help entry for that specific item. In this case:

SHADING-SCHEDULE

Takes the U-name of a SCHEDULE (with TYPE=MULTIPLIER) that defines hourly values of a multiplier on the solar gain through the window. This represents the shading effect of movable devices such as blinds, drapes, or shutters. Items that change solar transmission may also affect heat conduction. If so, a matching CONDUCT-SCHEDULE should be used. If the SHADING-SCHEDULE is not input, the schedule will default to 1.0 for all hours.

?Solar gain? is the load incident on a space as a result of the sun/sky?s energy entering through a fenestration and being absorbed/interreflected by internal surfaces (floors/people/furniture?), manifesting as heat radiation in the process. If you have a window device or seasonal treatment that varies not only the light coming in but also appreciably affects the conductive transfer of heat through the window/frame opening, then define a CONDUCT-SCHEDULE as well to account for those effects.

An aside to clear up a potential source of confusion: building shades can optionally be given a SHADE-SCHEDULE, which is in practice/function very similar to a SHADING-SCHEDULE for windows. These two terms are used interchangeably here on the lists, at times... may be helpful if you?re searching the archives for more info ;).

~Nick

NICK CATON, P.E.

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I sense a vocabulary jumble? I don?t consider myself an expert in the science of window performance, but I think sharing my understanding may help you in this case:

?Shading Coefficient? is a property that describes how much solar energy passes through a glazing relative to single pane clear float glass*. Strictly speaking, it does not include frame or other opaque elements, but sometimes by context people will discuss an SC for an entire window assembly... SHGC is more commonly used to describe ?whole assembly? performance.

Fractional shading schedule values in eQuest define how much light gets through an entire window assembly, relative to the same assembly having no additional shading device at all.

They?re similar in concept, but not quite the same thing?

I would encourage you to google the terms and feel comfortable understanding the difference before choosing a course of action. This article looks promising: http://www.commercialwindows.umn.edu/issues_energy2.php

~Nick

* Newer eQuest users: note Glass Type #1000 in the DOE2 Glass Library (accessible in the context menu after right-clicking most fields and after ?Tutorials and references?) is this exact case: SC = 1.

NICK CATON, P.E.

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