[esp-r] Re: esp-r Digest, Vol 13, Issue 10 HELP - Ploycarb/Perspex

[George Wallis]

Are there any values available for double thickness polycarb, such as would
be used in a large greenhouse?

Regards

George

-----Original Message-----
From: esp-r-bounces at lists.strath.ac.uk
[mailto:esp-r-bounces at lists.strath.ac.uk] On Behalf Of
esp-r-request at lists.strath.ac.uk
Sent: 22 August 2007 12:00
To: esp-r at lists.strath.ac.uk
Subject: esp-r Digest, Vol 13, Issue 10

Send esp-r mailing list submissions to
	esp-r at lists.strath.ac.uk

To subscribe or unsubscribe via the World Wide Web, visit
	http://lists.strath.ac.uk/mailman/listinfo/esp-r
or, via email, send a message with subject or body 'help' to
	esp-r-request at lists.strath.ac.uk

You can reach the person managing the list at
	esp-r-owner at lists.strath.ac.uk

When replying, please edit your Subject line so it is more specific
than "Re: Contents of esp-r digest..."


Today's Topics:

   1.  Types of glass (Ing Liang Wong)
   2. Re: Types of glass (Jon Hand (clcv10))


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

Message: 1
Date: Wed, 22 Aug 2007 10:21:44 +0100
From: "Ing Liang Wong" <ing.wong at ulster.ac.uk>
Subject: [esp-r]  Types of glass
To: <esp-r at lists.strath.ac.uk>
Message-ID: <000d01c7e49d$dc235550$19873dc1 at wongcst>
Content-Type: text/plain; charset="big5"

Dear all,

I have a look at the types of glass and optical properties of the
double-glazing (6-12-6mm) in ESP-r database and have a few questions.

The absorptions at the external and internal clear float glass layers are
taken from DCF7671_06nb, which appear to be:
0.157 0.172 0.185 0.201 0.202
0.117 0.124 0.127 0.112 0.077

1) Why are these values be so different, given the internal and external
have the same thickness (both are 6mm thick)?

2) What are the type of glass used for double glazing? In construction
database, plate glass has been used for the double-glazed windows; however,
the optical properties are for clear float glass with vis transmittance of
0.76.

Regards,
Wong
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.strath.ac.uk/archives/esp-r/attachments/20070822/e21ce31e/attac
hment-0001.html 

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

Message: 2
Date: Wed, 22 Aug 2007 11:00:58 +0100
From: "Jon Hand (clcv10)" <jon at esru.strath.ac.uk>
Subject: [esp-r] Re: Types of glass
To: "Ing Liang Wong" <ing.wong at ulster.ac.uk>
Cc: esp-r at lists.strath.ac.uk
Message-ID: <4D30ECF6-BBCB-4826-84E4-115AF6421C4B at esru.strath.ac.uk>
Content-Type: text/plain; charset="us-ascii"


A recent question about optical properties (outside and inside panes)

> The absorptions at the external and internal clear float glass  
> layers are taken from DCF7671_06nb, which appear to be:
> 0.157 0.172 0.185 0.201 0.202
> 0.117 0.124 0.127 0.112 0.077

The treatment of optical properties, as calculated by tools such as  
WIS and
Window 5.2 and used by simulation tools such as ESP-r are based on
absorption being calculated from the outside to the inside.

The absorption of an inner layer, is, by tradition, calculated  
"relative" to that of
an outer layers.  Another way of saying this is if 100 units reach  
the outer glass
and it absorbs 40 units any inside layers of glass can only know  
about the
remaining 60 units rather than the initial 100 units.  The values  
seen in the
optical database take this into account.

In ESP-r the thermophysical properties of glass are held separately from
the optial properties of the glass.  A thermophysical material  
labeled as
clear float might have a range of possible optical properties.  It is  
up to
authors that define databases and the links between databases to ensure
that the names of the entities are clear and the correct associations
are defined.  It is certainly the case that some of the names that have
been given to database entities are a bit opaque.  We are working  
towards
allowing longer (and hopefully more expressive names).

-ESRU
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.strath.ac.uk/archives/esp-r/attachments/20070822/4c811d2e/attac
hment-0001.html 

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

_______________________________________________
esp-r mailing list
esp-r at lists.strath.ac.uk
http://lists.strath.ac.uk/mailman/listinfo/esp-r

End of esp-r Digest, Vol 13, Issue 10
*************************************