[TRNSYS-users] Getting COPs greater than the rated in an absorption chiller

[Shahen Fakhraldin]

Dear TRNSYS user,

Did anyone face a problem of getting COPs greater than the rated one in a solar assisted absorption system? Where COP rises to around (0.8) at the start of the simulation and gets down to an average (0.75) for the rest of the day, whilst the rated cop is (0.7).
I assumed the set point temp for the Aux heater 70 C and the timestep was 1min

In my project, a cold tank (type 4) is used to connect between the chiller and the building, with the aid of using type 682 to impose the load.
Is it resulted from a mistake in the connections of the cold tank? 


Down below are the links, where a&b for chiller-tank loop and c&d for tank-load loop
a- Chilled water temperature and flow rate (chiller107) ---->> Cold-side temperature and flow rate (cold tank)

b- Temperature (and flow rate) to load (cold tank) --->> Chilled water inlet temp and flow rate (chiller) trough a constant speed pump
c- Outlet temperature and flow rate (type 682) --->> Hot-side temperature and flow rate (cold tank) through a pump

d- Temperature (and flow rate) to heat source (cold tank) --->> Inlet temperature and flow rate of type 682

Am I right? If yes, are there other reasons, such as the set point temp of the Aux heater, that might cause this error?

Kind regards,
Shahen
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