Valeooscope - Air Conditioning System Thermal comfort loop

10. The Air conditioning Loop

10.2.1 Boiling temperature vs pressure The boiling point of the refrigerant governs heat exchanges in the condenser and in the evapora- tor: the refrigerant will evaporate or condense depending on the heat exchange direction.

2. The fluid in the CONDENSER condenses during the thermal exchange with the cooler air from the exterior environment, thereby expelling the heat to the exterior. g Two phase changes (evaporation / condensation) g Two phase changes at two different pressures g Two heat exchanges in two heat exchangers (evaporator / condenser)

1. The fluid in the EVAPORATOR evaporates during the thermal exchange with the hot air from the exterior environment, thereby cooling down the cabin.

LOW PRESSURE SIDE

HIGH PRESSURE SIDE

Absolute pressure (bar)

Boiling temperature (°C)

Absolute pressure (bar)

Boiling temperature (°C)

R134a

2,34 2,53 2,72 2,93 3,15 3,38 3,62 3,88 4,43 5,04 5,72

-6,0°C -4,0°C -2,0°C 0,0°C 2,0°C 4,0°C 6,0°C 8,0°C 12,0°C 16,0°C 20,0°C

6,46 9,12 9,63

24,0°C 36,0°C 38,0°C 40,0°C 42,0°C 44,0°C 48,0°C 52,0°C 56,0°C 60,0°C 70,0°C

10,17 10,72 11,30 12,53 13,85 15,28 16,82 21,17

Evaporator

Condenser

Blower

Cooling fan

Heating the refrigerant initiates its evaporation inside the evaporator

Cooling the refrigerant initiates its condensation inside the condenser

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