[TRNSYS-users] direct expansion solar assisted heat pump

[David BRADLEY]

I think you might be best off trying to model that type of heat pump 
using a performance map instead of trying to model the whole 
refrigeration cycle. Typically the dynamics of a refrigeration cycle 
have a very very short time constant while the dynamics of a solar 
collector (due to its mass) have a longer time constant. Getting a 
correct first-principals model of the refrigerant evaporation and the 
energy transfer within the fins and tubes of the solar collector might 
be difficult. However, if you can get information about the COP of the 
heat pump under different circumstances, you might be able to mimic the 
way that most other heat pumps are modeled (ie with a catalog-data 
lookup table approach).
Kind regards,
  David


On 3/12/2011 03:20, Enmisagh at aol.com wrote:
> dear all,
> I was wondering you to give me an idea to model a direct expansion 
> solar assisted heat pump? In this heat pump , a flat plate collector 
> has the role of evaporator and refrigerant circulates in tubes of 
> collector . other components are similar to conventional heat pump  Is 
> there any special type for this application or I have to simulate 
> every part of refrigeration cycle separately?
> best regad,
>
>
> _______________________________________________
> 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

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