Trane CVGF1000, Инструкция по установке, эксплуатации и обслуживанию

Страница: 33 / 128

Compressor second stage -
Refrigerant vapor leaving the first stage compressor is mixed with cooler refrigerant
vapor from the economizer. This mixing lowers the enthalpy of the vapor entering the
second stage. The second stage impeller accelerates the vapor, further increasing its
temperature and pressure to state point 4.
Condenser - Refrigerant vapor enters the condenser where the system cooling load
and heat of compression are rejected to the condenser water circuit. This heat rejec-
tion cools and condenses the refrigerant vapor to a liquid at state point 5.
Economizer and refrigerant orifice system -
Liquid refrigerant leaving the condenser at state point 5 flows through the first orifice
and enters the economizer to flash a small amount of refrigerant at an intermediate
pressure labeled P1. Flashing some liquid refrigerant cools the remaining liquid to
state point 8.
Another benefit of flashing refrigerant is to increase the total evaporator Refrigeration
Effect from RE’ to RE. The economizer provides around 4 percent energy savings com-
pared to chillers with no economizer.
To complete the operating cycle, liquid refrigerant leaving the economizer at state
point 8 flows through a second orifice.
Here refrigerant pressure and temperature are reduced to evaporator conditions at
state point 1.
An innovative design feature of the CVGF chiller is maximizing the evaporator heat
transfer performance while minimizing refrigerant charge requirements. This is accom-
plished by the Trane-patented falling film evaporator design. The amount of refrigerant
charge required in CVGF is less than that in comparably sized chillers of flooded evap-
orator design.
CVGF-SVX03B-EN
33
General Information