Difference Between Charge Air Cooler And Intercooler

Difference Between Charge Air Cooler and Intercooler

A charge air cooler, or CAC, is commonly used in turbocharged or supercharged internal combustion engines. Its principal function is to cool compressed air from the turbocharger or supercharger before entering the engine's cylinders.
For example, in a diesel engine found in a heavy-duty vehicle, the turbocharger compresses the intake air to a high pressure. The charge air cooler then lowers the temperature of the compressed air. This cooler, denser air enables more efficient combustion in the engine, resulting in improved power production and lower emissions.

Intercoolers are used in multi-stage compression systems, including industrial air compressors and high-performance engines with sequential turbocharging. Its aim is to chill the air between phases of compression.
In a two-stage compressor, the air is compressed in the first stage before passing through the intercooler. Cooling the air after the first stage reduces its volume, allowing it to compress farther in the second stage and improving overall compression efficiency.

The Cooling Medium and Heat Transfer Mechanism
Charge air coolers typically employ ambient air as a cooling medium. They have a heat exchanger design, typically a fin-and-tube or plate-type heat exchanger. The heated compressed air runs through the tubes or channels, while the ambient air flows over the fins or plates, removing heat from the compressed air.
In some cases, vehicle charge air coolers may employ engine coolant in addition to ambient air to provide more effective cooling under certain conditions.
Intercoolers can also use ambient air as the cooling medium in a similar fin - and - tube or plate - heat - exchanger setup. However, in some industrial applications, water - cooled intercoolers are also used. In a water - cooled intercooler, water is circulated through a separate set of channels in the heat exchanger to absorb heat from the compressed air.