Heat Pump

Heat Pump (Air Conditioner System)

Memindahkan panas dari tempat bersuhu rendah (Tc) ke lokasi bersuhu lebih tinggi (Th), dengan adanya pasokan energi.

1. Condenser coil (hot side heat exchanger) ==> HOT
2. Expansion valve
3. Evaporator coil (cold side heat exchanger) ==> COLD
4. Compressor
Efficiency (Coeff. of Performance)
COP = Q/W
Qcond = Qevap + Qcompressor
QH = QC + W, so W = QH - QC

COP heating (using AC at the winter) = QH / (QH - QC)
= Th/(Th - Tc)
COP cooling (using AC at the summer/refrigerator) = QC / (QH - QC)
= Tc/(Th - Tc)
COP cooling = COP heating - 1

Cycle
1. Condensing ---> isothermal, isobaric, entropy and enthalpy are decreased
2. Expansion ----> isentropic, P and T are decreased (reversible)
3. Evaporation --> isothermal, isobaric, entropy and enthalpy are increased
4. Compression--> isentropic, P and T are increased (reversible)

In the real cycle, the expansion and compression are not isentropic, or the processes are irreversible and the entropy isn't constant.