[TRNSYS-users] question about the type 651

[Jeff Thornton]

<I can't understand well enough the calculation for condensate conditions
in the source code of type 651 and its description in tess library.
 Why  T_CONDENSATE=T_EVAP_OUT ? why it's not
T_condensate=Tcondensate_in-Q_rejection/flow_condensate ?>

I think you may have misunderstood the term "condensate".  The condensate
is the LIQUID water that condenses from the air stream as the air passes
across the cooling coil and is then drained from the coil.  The
temperature of the condensed water is set to the temperature of the air
leaving the coil.  It wouldn't make sense to have the condensed liquid
water temperature be calculated by dividing the coil heat transfer by the
flow rate (and specific heat).

<Why flow rate_condensate = flow rate_evaporator x difference humidity
ratio via evaporator?>

That's the mass balance (psychrometric) calculation for the amount of
water condensed from the air stream as it passes across the coil.

And why EER = COP*3.413 ? What does it means 3.413 ?

COP is dimensionless, EER is not.  3.413 is the conversion factor between
the units.

Jeff



Jeff Thornton
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