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chemicalENG
12-01-2015, 04:14 PM
If the condensing temperature and evaporating temperature is constant but the power of the compressor ( driven by gas turbine ) changed . Can be assume that the coefficient of performance is constant ?

Rob White
12-01-2015, 04:49 PM
.

No.

The coefficient is a calculation of the energy imparted through the
compression process divided into the energy absorbed or rejected
through the heat exchanger.

COP = RE/WD
COP = THR/WD

RE being refrigeration effect, heat absorbed by evap.
THR being total heat rejected in cond.
WD being work done in compression process.

Rob

.

chemicalENG
12-01-2015, 05:20 PM
.

No.

The coefficient is a calculation of the energy imparted through the
compression process divided into the energy absorbed or rejected
through the heat exchanger.

COP = RE/WD
COP = THR/WD

RE being refrigeration effect, heat absorbed by evap.
THR being total heat rejected in cond.
WD being work done in compression process.

Rob

.


ok

If coefficient of performane is 2 . It means the refrigerant removes 2 units of heat for each unit of energy consumed , right ?

So If the work input is 1 kW the refrigeration effect is 2 kW

Now , if the work input 2 kW , is the refrigeration effect will be 4 kW ??

If that true , It means that the coefficient of performance is constant ????

Rob White
12-01-2015, 06:08 PM
ok

If coefficient of performane is 2 . It means the refrigerant removes 2 units of heat for each unit of energy consumed , right ?

So If the work input is 1 kW the refrigeration effect is 2 kW

Now , if the work input 2 kW , is the refrigeration effect will be 4 kW ??

If that true , It means that the coefficient of performance is constant ????

OK, sorry in that context "yes".

COP is a ratio, nothing more so inputs and outputs can change but
the ratio could remain constant.

Rob

.