[TRNSYS-users] Glazed air collector

[David BRADLEY]

Nidal,
   There are a couple of things you need to be a little bit cautious 
about in this. First, Type539 only accounts for sensible heating and 
cooling. The assumption is that the absolute humidity ratio of the air 
entering and leaving the collector is the same. During daytime, this is 
likely not a problem but because the temperature changes through the 
collector, you'll need to put a Type33 at the outlet in order to 
correctly recalculate the outlet air relative humidity. Second, Type539 
does not take into account longwave radiation loss that typically 
happens at night. Your working fluid will only cool down to ambient, not 
below it. While this is true for both water and air based collectors, 
the impact is a little more important for air-based collectors because, 
as I mentioned in the first caution, the Type only handles sensible 
energy so while in real life you might get some condensation occurring 
inside the collector at night, this effect will not be seen in the model.
Best,
  David


On 10/26/2012 17:33, Nidal Abdalla wrote:
> Dear Matt
> Thank you v.much for your reply.
> Nidal Abdalla
> *From:* Matt Duffy <duffy at tess-inc.com>
> *To:* Nidal Abdalla <nidalabdalla at yahoo.com>
> *Cc:* trnsys-users at cae.wisc.edu
> *Sent:* Friday, October 26, 2012 7:26 PM
> *Subject:* Re: [TRNSYS-users] Glazed air collector
>
> Dear Nidal Abdalla,
> I have used Type539 (Glazed Flat Plate Solar Collector from TESS Solar 
> Library) with success for a solar air collector. Since the solar air 
> collector was here in the states, they had the SRCC rating numbers for 
> the efficiency and IAM's, so I could simply enter those numbers into 
> the parameters of Type539.  Since this solar collector model and many 
> others in TRNSYS assume a constant fluid specific heat, you can 
> implement solar air heating simulations with them.
> Best regards,
> Matt Duffy
> On 2012-10-16 16:15, Nidal Abdalla wrote:
>> Dear all
>> I am trying to simulate glazed air collector for space heating using 
>> TRNSYS 17 with TESS libraries. Anyone can recommend the best choice 
>> for collector type can be used? I found at the TRNSY archives 2010 
>> that  Mr. David had mentioned that there are a number of air-based 
>> solar collectors available in the TESS Solar Component. In fact, I 
>> found only unglazed air collector in the TESS lib. I am wondering if 
>> someone can help me.
>> Regards
>> Nidal Abdalla
>> National Energy Research Center
>> Amman - Jordan
>
>
>
>
> _______________________________________________
> TRNSYS-users mailing list
> TRNSYS-users at cae.wisc.edu
> https://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:+1.608.278.1475
d.bradley at tess-inc.com

http://www.tess-inc.com
http://www.trnsys.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20121029/6b3595dc/attachment-0005.htm>