charge air cooled engines

[chhitiz]

could anyone tell me how the charge air is used to cool the engine in a charge air-cooled engine?(i mean apart from the charge coming in and cooling, is there a mechanism for cooling the charge before intake)

[brewnog]

Charge air cooling isn't used to cool the engine. It is used to increase the density of the intake charge, to allow more fuel to be burnt, or to improve emissions.

The process is this: Incoming air to the engine is compressed in the compressor of a turbocharger or supercharger. The air gets hot, so is cooled in a charge cooler, before being fed into the cylinders. The charge cooler is either air-to-air (in which case the cooler is cooled by airflow, usually forced) or air-to-water, in which case the heat is rejected to a water circuit (often engine coolant, sometimes a secondary circuit).