[Equest-users] Queries

[Demba Ndiaye]

It make think of the sign convention used in Thermodynamics. You have the System and its Surroundings. Let's say that the System is the building.

In Thermo, heat received by the system from its surroundings (cooling load) is "positive". The heat lost by the system to its surroundings (heating load) is "negative".

It is the inverse for work.

_____________
Demba NDIAYE

From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Pasha Korber-Gonzalez
Sent: Tuesday, May 04, 2010 5:25 AM
To: Piyush Varma
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Queries

Piyush,

I can help with 01., but I do not understand the concept of alternating solar gain factor that you are referring too, or maybe I just don't understand the question exactly.

For 01. I have always known the symbols of heating energy to be referenced as (+) for cooling and (-) for heating although I can't give you the exact reference this nomenclature comes from.  In terms of the positive for cooling energy it is a description for heat energy being present in the conditioned space(s)/building in terms of heat energy being gained (or generated.)  Where the negative symbol is used to represent heating energy this is describing that heat energy from the space/zone is being lost via....whatever the mechanism (i.e. ext. wall or window conduction losses, to exhaust air heat energy loss from the building, to infiltration effects, etc.)

As long as you can keep your symbols managed with in your own simulation work don't let this little quirk stop you from reporting your numbers in your preferred format.  It is good that you are asking these types of detail questions so that you can ensure your own foundation of understanding for the tools you use.  This is what makes a good energy simulator.   Keep asking questions, this list is a HUGE benefit from my experience.

pasha
On Tue, May 4, 2010 at 2:55 AM, Piyush Varma <varpiyush at gmail.com<mailto:varpiyush at gmail.com>> wrote:
Hi all,

I am an eQuest newbie and had 2 small queries which hopefully would be answered.

01. What's the logic behind eQuest giving positive (+ve) Cooling Loads & (-ve) negative Heating Loads. (I made an Admittance Method Algorithm & it gives me the opposite values, eQuest i.e. negative cooling loads & +ve heating loads, have checked all sign convention...can't figure out why? My algorithm simulates for Delhi's (India) climate predominantly, cooling loads.

02. I have asked this before...is there any library for data of alternating solar gain factors, especially for Delhi, India. (As far as i believe it does'nt take into account the alternating solar gain factor...)

hope these get resolved soon, thanks in advance.

Regards,
Piyush

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG<mailto:EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20100504/fc196b19/attachment-0001.htm>