Indirect or water charge air cooling (WCAC) technology offers firstly the possibility of charge air thermal management by regulating the coolant flow and secondly the possibility to reduce the air volume between compressor of the turbocharger and the intake ports of the engine.
This technology provides a solution between the conflicting targets of compact packaging, the achievement of the charge air cooler thermal performance target and the reduction of gas side pressure drop and in that way contributes to improved transient engine behavior.
The WCAC integrated in the air intake offers less architectural complexity, intake air temperature stability independent of engine load as well as improved transient behavior of the engine due to the reduction of charge air volume and charge air side pressure drop compared to a conventional charge air path with air charge air cooling (ACAC) systems. For engines equipped with a low pressure (LP) exhaust gas recirculation (EGR) system, the charge air thermal management is enabled by regulation of the coolant flow and thus condensation effects and icing can be avoided.
Valeo has developed a modular range of WCAC air intake modules and WCAC components. The range covers the requirements of both Diesel and Gasoline engines from 2 cyl. to 8 cyl. Specific focus was given to the development of corrosion resistance improved heat exchanger materials to withstand the engine environment due to the use of recirculated exhaust gas.
Valeo is a leading player in this field having introduced world-wide first to the market the WCAC for both 4cyl Gasoline in 2007and Diesel engines in 2011.