[TRNSYS-users] Total heating demand (??)
Jochen Doell
jochen.doell at ise.fraunhofer.de
Fri Jan 7 02:07:42 PST 2011
Dear Wang,
Regarding your first question: I suspect the thermal capacity of the
floor to cause the difference between case 2 and 3. Simulate a larger
time period and this effect should get smaller.
About your second question, floor or wall heating systems are more
efficient than radiator based heating systems because they demand lower
inlet (or forward) temperatures. By this boiler (and potential storage)
efficiency increases. Since you do not simulate any heat generation,
these effects do not occur in your simulation.
I expect the Qheat of case 1 to be the real heat demand and QALFL_Inlet
of case 2 to be the heat delivered to the room by the active layer.
Hope this helps.
Best regards,
Jochen
trnsys-users-request at cae.wisc.edu schrieb:
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> ------------------------------------------------------------------------
>
> Today's Topics:
>
> 1. Total heating demand (??)
> 2. Re: question about wall gain (Knut Erik Enerstvedt)
> 3. Re: question about wall gain (salim mokraoui)
>
>
> ------------------------------------------------------------------------
>
> Betreff:
> [TRNSYS-users] Total heating demand
> Von:
> 王洋 <wanghongyang1767 at gmail.com>
> Datum:
> Thu, 6 Jan 2011 21:16:10 +0100
> An:
> trnsys-users at cae.wisc.edu
>
> An:
> trnsys-users at cae.wisc.edu
>
>
> Dear all,
>
> Happy new year!
>
> I have a question about calculating total heating demand:
>
> There is one same room to keep indoor temperature as 20°C one day 24 hours,
> the initial indoor temperature is 20°C, there is no infiltration no other
> internal gains in the room. I used 3 different methods to calculate total
> heating demand of one day, separately.
>
> 1.First is heating in TRNBuild: after using the INTEGRATOR TYPE 46, the
> QHEAT is about 34314 kJ.
>
> 2.Second is floor heating(active layer): after using the INTEGRATOR TYPE 46,
> the QALFL_Inlet is about 33680.7kJ.
>
> 3.Third is still floor heating(active layer): after using the INTEGRATOR
> TYPE 46, but I used Q=CwaterMwater(Tinlet-Toutlet), the result of Q is
> 144639kJ.
>
> My question is: 1) To 2 and 3: Why is the difference is so large? 3 is
> almost 4 times than 3? I will get the total heating demand, which one is
> right? Why? What's different of both of them?
>
> 2) If 3 is right. Generally, the floor heating should be more energy-saving
> than common heating. But here result is absolutely opposite. The common
> heating is more energy-heating. Why? Here what difference of common heating
> and floor heating?
>
> Many thanks!
>
> Br.
>
> wang
> 在 2011年1月5日 下午7:55，王洋 <wanghongyang1767 at gmail.com>写道：
>
>
>> Dear all,
>>
>> Happy new year!
>>
>> I have a question about calculating total heating demand:
>>
>> There is one same room to keep indoor temperature as 20°C one day 24 hours,
>> the initial indoor temperature is 20°C, there is no infiltration no other
>> internal gains in the room. I used 3 different methods to calculate total
>> heating demand of one day, separately.
>>
>> 1.First is heating in TRNBuild: after using the INTEGRATOR TYPE 46, the
>> QHEAT is about 34314 kJ.
>>
>> 2.Second is floor heating(active layer): after using the INTEGRATOR TYPE
>> 46, the QALFL_Inlet is about 33680.7kJ.
>>
>> 3.Third is still floor heating(active layer): after using the INTEGRATOR
>> TYPE 46, but I used Q=CwaterMwater(Tinlet-Toutlet), the result of Q is
>> 144639kJ.
>>
>> My question is: 1) To 2 and 3: Why is the difference is so large? 3 is
>> almost 4 times than 3? I will get the total heating demand, which one is
>> right? Why? What's different of both of them?
>>
>> 2) If 3 is right. Generally, the floor heating should be more energy-saving
>> than common heating. But here result is absolutely opposite. The common
>> heating is more energy-heating. Why? Here what difference of common heating
>> and floor heating?
>>
>> Many thanks!
>>
>> Br.
>>
>> wang
>>
>>
>> 在 2011年1月5日 下午2:38，王洋 <wanghongyang1767 at gmail.com>写道：
>>
>> Dear all,
>>
>>> Happy new year!
>>>
>>> I have a question about calculating total heating demand:
>>>
>>> There is one same room to keep indoor temperature as 20°C one day 24
>>> hours, the initial indoor temperature is 20°C, there is no infiltration no
>>> other internal gains in the room. I used 3 different methods to calculate
>>> total heating demand of one day, separately.
>>>
>>> 1.First is heating in TRNBuild: after using the INTEGRATOR TYPE 46, the
>>> QHEAT is about 34314 kJ.
>>>
>>> 2.Second is floor heating(active layer): after using the INTEGRATOR TYPE
>>> 46, the QALFL_Inlet is about 33680.7kJ.
>>>
>>> 3.Third is still floor heating(active layer): after using the INTEGRATOR
>>> TYPE 46, but I used Q=CwaterMwater(Tinlet-Toutlet), the result of Q is
>>> 144639kJ.
>>>
>>> My question is: 1) To 2 and 3: Why is the difference is so large? 3 is
>>> almost 4 times than 3? I will get the total heating demand, which one is
>>> right? Why? What's different of both of them?
>>>
>>> 2) If 3 is right. Generally, the floor heating should be more
>>> energy-saving than common heating. But here result is absolutely opposite.
>>> The common heating is more energy-heating. Why? Here what difference of
>>> common heating and floor heating?
>>>
>>> Many thanks!
>>>
>>> Br.
>>>
>>> wang
>>>
>>>
>>>
>>> 2011/1/4 <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
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>>>>
>>>> When replying, please edit your Subject line so it is more specific
>>>> than "Re: Contents of TRNSYS-users digest..."
>>>>
>>>> Today's Topics:
>>>>
>>>> 1. optimization problems using trnopt in Windows 7 OS (Dapeng Li)
>>>>
>>>>
>>>> ---------- 已转发邮件 ----------
>>>> From: Dapeng Li <jiap1120 at gmail.com>
>>>> To: TRNSYS-users at cae.wisc.edu
>>>> Date: Tue, 4 Jan 2011 18:00:38 +0100
>>>> Subject: [TRNSYS-users] optimization problems using trnopt in Windows 7
>>>> OS
>>>> Dear all,
>>>>
>>>> I want to do optimization using trnsys, trnopt and genopt in* Windows 7
>>>> OS. *But when I run the example in the directory of "C:\Program
>>>> Files\Trnsys16_1\Optimization", I got a error message in Genopt interface
>>>> that is enclosed in the attachment.
>>>>
>>>> The version I use is listed below: TRNSYS version 16.01.0003, trnopt
>>>> version 2.1.0.52, genopt version 2.1.0 June 18, 2008.
>>>>
>>>> PS: I ever did optimization in XP OS, and it work well.
>>>>
>>>> Thanks in advance.
>>>>
>>>> With kind regards,
>>>>
>>>> Dapeng Li
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> TRNSYS-users mailing list
>>>> TRNSYS-users at cae.wisc.edu
>>>> https://mailman.cae.wisc.edu/listinfo/trnsys-users
>>>>
>>>>
>>>>
>
>
>
> ------------------------------------------------------------------------
>
> Betreff:
> Re: [TRNSYS-users] question about wall gain
> Von:
> Knut Erik Enerstvedt <knut.erik.enerstvedt at gmail.com>
> Datum:
> Fri, 7 Jan 2011 09:18:20 +0100
> An:
> duffy at tess-inc.com, salim.mokraoui at lermab.uhp-nancy.fr,
> trnsys-users at cae.wisc.edu
>
> An:
> duffy at tess-inc.com, salim.mokraoui at lermab.uhp-nancy.fr,
> trnsys-users at cae.wisc.edu
>
>
> Dear Matt and Salim,
>
>
> One example of usage for "wall gain" is when you have defined a boundary
> wall with known boundary temperature, but also want to take into account
> solar gain from windows on that wall. You can not (at least in TRNSYS 16)
> define windows in the normal manner on boundary walls. For example, if you
> are modelling a zone adjacent to a highly glazed building with known
> temperature, and a glass wall separates the two. Then you can use "wall
> gain" to impose the solar heat flux from the adjacent building on the
> boundary wall.
>
>
> Best regards,
>
> Knut Erik Enerstvedt
>
>
>
>
>> Dear Salim,
>>
>
>
>> To the best of my knowledge, and according to the documentation, it is
>>
> indeed an energy flux to the inside wall surface. When does one >use this, I
> am not exactly sure. Perhaps when there is chimney in a wall with hot
> exhaust gases that is causing a gain to the zone?
>
>
>> Best regards,
>>
>
>
>> Matt
>>
>
>
>
> *>----- Original Message -----*
> *>From:* "salim mokraoui" <salim.mokraoui at lermab.uhp-nancy.fr>
> *>Sent:* Wed, January 5, 2011 9:23
> *>Subject:* [TRNSYS-users] question about wall gain
>
>
>> Dear trnsys users,
>>
>
>
>
>
>> In zone window of trnbuild, what does wall gain means actually, is it a
>>
> density flux that we impose at the inside surface of the wall ?
>
>
>
>
>> Many thanks
>>
>
>
>
>
>> Salim MOKRAOUI
>>
>
>
>> Faculté des sciences de Nancy - LERMAB
>>
>
>
>> BP 239
>>
>
>
>> 54506 Vandoeuvre.
>>
>
>
>> Tél 03 83 68 48 44 - mél salim.mokraoui at lermab.uhp-nancy.fr
>>
>
>
>
> ------------------------------------------------------------------------
>
> Betreff:
> Re: [TRNSYS-users] question about wall gain
> Von:
> "salim mokraoui" <salim.mokraoui at lermab.uhp-nancy.fr>
> Datum:
> Fri, 7 Jan 2011 10:06:01 +0100
> An:
> "'Knut Erik Enerstvedt'" <knut.erik.enerstvedt at gmail.com>,
> <duffy at tess-inc.com>, <trnsys-users at cae.wisc.edu>
>
> An:
> "'Knut Erik Enerstvedt'" <knut.erik.enerstvedt at gmail.com>,
> <duffy at tess-inc.com>, <trnsys-users at cae.wisc.edu>
>
>
> Dear Erik and Matt,
>
>
>
> Thank you very much for your answers.
>
> I can understand that this wall gain concerns only a radiative gains, is it
> right ?
>
>
>
> Best regards
>
>
>
> De : Knut Erik Enerstvedt [mailto:knut.erik.enerstvedt at gmail.com]
> Envoyé : vendredi 7 janvier 2011 09:18
> À : duffy at tess-inc.com; salim.mokraoui at lermab.uhp-nancy.fr;
> trnsys-users at cae.wisc.edu
> Objet : Re: [TRNSYS-users] question about wall gain
>
>
>
> Dear Matt and Salim,
>
>
>
> One example of usage for "wall gain" is when you have defined a boundary
> wall with known boundary temperature, but also want to take into account
> solar gain from windows on that wall. You can not (at least in TRNSYS 16)
> define windows in the normal manner on boundary walls. For example, if you
> are modelling a zone adjacent to a highly glazed building with known
> temperature, and a glass wall separates the two. Then you can use "wall
> gain" to impose the solar heat flux from the adjacent building on the
> boundary wall.
>
>
>
> Best regards,
>
> Knut Erik Enerstvedt
>
>
>
>
>
>
>> Dear Salim,
>>
>
>
>> To the best of my knowledge, and according to the documentation, it is
>>
> indeed an energy flux to the inside wall surface. When does one >use this, I
> am not exactly sure. Perhaps when there is chimney in a wall with hot
> exhaust gases that is causing a gain to the zone?
>
>
>> Best regards,
>>
>
>
>> Matt
>>
>
>
>
>
>
>> ----- Original Message -----
>> From: "salim mokraoui" <salim.mokraoui at lermab.uhp-nancy.fr>
>> Sent: Wed, January 5, 2011 9:23
>> Subject: [TRNSYS-users] question about wall gain
>>
>
>
>> Dear trnsys users,
>>
>
>
>
>
>> In zone window of trnbuild, what does wall gain means actually, is it a
>>
> density flux that we impose at the inside surface of the wall ?
>
>
>
>
>> Many thanks
>>
>
>
>
>
>> Salim MOKRAOUI
>>
>
>
>> Faculté des sciences de Nancy - LERMAB
>>
>
>
>> BP 239
>>
>
>
>> 54506 Vandoeuvre.
>>
>
>
>> Tél 03 83 68 48 44 - mél salim.mokraoui at lermab.uhp-nancy.fr
>>
>
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> TRNSYS-users mailing list
> TRNSYS-users at cae.wisc.edu
> https://mailman.cae.wisc.edu/listinfo/trnsys-users
>
--
_________________________________________________
Dipl.-Ing. (FH) Jochen Döll
Dept. Thermal Systems and Buildings
Fraunhofer-Institut für Solare Energiesysteme ISE
Heidenhofstrasse 2, 79110 Freiburg, Germany
Phone: +49 (761) 4588-5468
Fax: +49 (761) 4588-9000
Mail: jochen.doell at ise.fraunhofer.de
Web: www.ise.fraunhofer.de
_________________________________________________
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