[TRNSYS-users] EQUATION

[王洋]

Dear all,

          Please tell me how to set an equation:

         OF=1, when CO2%>1000

         OF = 0, when CO2%< 700

      Thanks!

       wang

在 2011年11月2日 下午12:14，王洋 <wanghongyang1767 at gmail.com>写道：

> Dear all,
>
>     Which experts can tell me a question about air density?
>
>     In TRNbuild  PROPERTIES about air density 1.2 kg/m^3: Is it a initial
> value? If outdoor temperature changes in TrnFlow, this air density value
> will change as the teperature or it is a constant?
>
>    Thanks!
>
>     wang
>
>
>
> 2011/11/1 <trnsys-users-request at cae.wisc.edu>
>
>> Send TRNSYS-users mailing list submissions to
>>        trnsys-users at cae.wisc.edu
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>>        https://mailman.cae.wisc.edu/listinfo/trnsys-users
>> or, via email, send a message with subject or body 'help' to
>>        trnsys-users-request at cae.wisc.edu
>>
>> You can reach the person managing the list at
>>        trnsys-users-owner at cae.wisc.edu
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of TRNSYS-users digest..."
>>
>> Today's Topics:
>>
>>   1. Re: Information (David BRADLEY)
>>
>>
>> ---------- 已转发邮件 ----------
>> From: David BRADLEY <d.bradley at tess-inc.com>
>> To: "Adriana Gómez Aldana" <adrigomezaldana at gmail.com>
>> Date: Tue, 01 Nov 2011 11:35:52 -0500
>> Subject: Re: [TRNSYS-users] Information
>> Adriana,
>>   I had thought that I sent a response about this. In case it did not get
>> to you, here it is again:
>>
>> ...
>>   It would help to know a bit more about the configuration of your
>> system: what are you drying, is the material in a big lump, is it spread
>> out on shelves, is it moving, does it occupy most of the available space in
>> the chamber or a comparatively small part of the space, etc.)
>>
>>   I think you could probably use the Type56 multi-zone building model for
>> the drying chamber itself.
>>
>>   I would guess that you would need to write a new model for the material
>> that you are drying. If the material is quite spread-out then this might be
>> easily enough characterized by a first-order differential equation and you
>> even might be able to use Tess Type693. Type693 is intended to model a
>> thermal lumped capacitance that heats and cools according to a first-order
>> differential equation but I imagine that pricipals are basically the same
>> whether you are talking about thermal capacitance or moisture capacitance.
>>
>>   If the product is not spread out, if important moisture gradients
>> develop within it as it dries, or if its drying process is exothermic (like
>> it is for compost) then I think you would need to write your own model or
>> collaborate with someone who could write the model for you. In order to
>> write the model you would need to have access to a FORTRAN compiler such as
>> Intel Visual Fortran v11.x
>>
>>   Once you have the model of the drying substance, you would connect its
>> moisture loss to a moisture gain input of the building (drying chamber)
>> model.
>>
>> Kind regards,
>>  David
>>
>> On 10/30/2011 20:45, Adriana Gómez Aldana wrote:
>>
>>
>>
>>  Good Morning,
>>
>> I am a TRNSYS user since it is one of the tools for my phD thesis.
>> Currently, I am working in a solar drying problem and I would like to know
>> if there is a special module to simulate the drying chamber. If it is
>> possible to acquire this module, I would be very thankful if you can
>> explain me how is the procedure to access it.
>>
>> Thanks for your attention,
>>
>> Adriana Gómez
>> phD Student - Engineering Department
>> Universidad de los Andes
>> Bogotá, Colombia
>>
>>
>>
>>
>>
>> _______________________________________________
>> TRNSYS-users mailing listTRNSYS-users at cae.wisc.eduhttps://mailman.cae.wisc.edu/listinfo/trnsys-users
>>
>>
>> --
>> ***************************
>> David BRADLEY
>> Principal
>> Thermal Energy Systems Specialists, LLC
>> 22 North Carroll Street - suite 370
>> Madison, WI  53703 USA
>>
>> P:+1.608.274.2577
>> F:+1.608.278.1475d.bradley at tess-inc.com
>> http://www.tess-inc.comhttp://www.trnsys.com
>>
>>
>> _______________________________________________
>> TRNSYS-users mailing list
>> TRNSYS-users at cae.wisc.edu
>> https://mailman.cae.wisc.edu/listinfo/trnsys-users
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20111102/18fc37b0/attachment-0005.htm>