Charge Air Coolers Explained - All about Air Coolers | Vestas Aircoil

About Charge Air Coolers

What is a charge air cooler?

A charge air cooler is used to cool engine air after it has passed through a turbocharger, but before it enters the engine. This is their main function. The idea is to return the air to a lower temperature, for the optimum power from the combustion process within the engine.

More specifically, it is a heat exchange device used on turbocharged and supercharged (forced induction) internal combustion engines to improve their volumetric efficiency by increasing intake air-charge density through isochoric cooling. A decrease in air intake temperature provides a denser intake charge to the engine and allows more air and fuel to be combusted per engine cycle, increasing the output of the engine.

The charge air cooler is designed to cool the charged air from something in the region of 180°C to 220°C, down to around 40°C. It achieves this by using cooling water.

Charge air coolers range in size depending on the engine. The smallest are most often referred to as intercoolers and are attached to automobile or truck engines. The largest are often used on huge marine diesel engines or in power plants. They can weigh several tonnes in these circumstances.

Most are still associated with diesel engines, but Vestas aircoil manufactures specialist air coolers for gas engines too.

The first marine diesel engine charge air cooler was built by Vestas aircoil A/S in 1956. Look at our history here.

The phrase “charge air cooler” is an all-encompassing term, meaning that it cools the turbo’s charged air before it is routed into the engine.