A charge air cooler cools the combustion air after it has been compressed in the turbo charger. The process of turbo charging involves compressing the air which introduces energy in the form of heat. The air is cooled to the correct temperature for efficient use in the engine.
The air cooling is made possible by passing cool water (sea water or fresh water) through the charge air cooler tubes. There are fins attached the tubes that have the effect of increasing the surface area of the outer surface of the tube. This improves heat transfer.
The thermal design of an air cooler is of course critical. The engine performance could be badly affected if the charge air cooler is incorrectly designed. This is vital at new building, but equally so when the time comes for replacement.
Using OEM approved Vestas aircoil to replace an air cooler gives the owner a distinct advantage since the relationship Vestas has with the engine builders is historically strong. Access to data is vital. With data, one can make certain the design will work in the engine.
Charge air coolers range in size depending on the engine. The smallest are most often referred to as intercoolers and are attached to automobile engines or truck engines. The largest are reserved for use on huge marine diesel engines and can weigh over 2 tonnes.