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The future environmental constraints [e.g. WLTC +RDE, CAFE, Euro 6.2, 7] for the pollutant emissions lead to new challenges for the internal combustion engine. One of the solutions to decrease the fuel consumption, the CO2 and pollutant emissions whilst keeping the same driving and thermal comforts is the engine's thermal management, in particular during the warm-up phase. Furthermore, the traditional cooling system is not designed to work at the new engine transient thermal conditions at a non-optimal temperature in terms of fuel economy and exhaust emission. This paper describes a new technology for engine cooling systems that is able to control the coolant flow and temperature in relation to the engine conditions such as load and rotational speed. With a no flow in crankcase cooling strategy and a high engine temperature regulation, the Active Cooling Thermomanagement Valve succeeds in decreasing the fuel consumption without deteriorating engine's performance.

Unsteady intake wave dynamics have a first order influence on an engine's performance and fuel economy. There is an abundant literature particularly for naturally aspirated SI engines on the subject of intake manifolds and primary runner lengths aimed to achieve a tuned intake air line. A more demanding design for today's engines is to increase efficiency to meet the requirements of lower fuel consumption and CO2 emissions. Today's tendencies are downsizing the engine to meet these demands. And for drivability purposes, the engine is combined with a turbocharger coupled with a charge air cooler. However, when the engine's displacement is reduced, it will be very dependent on its boosting system. A particularly interesting point to address corresponds to the engine's operation in the low speed range and during transients where the engine has large pumping losses and poor boost pressure. This operation point can be optimized using acoustic supercharging techniques.

A new methodology for modeling engine intake has been presented; it is based on a transfer function relating pressure response and mass flow rate that makes use of the corresponding frequency spectrum obtained on the so-called “dynamic flow bench”. This new approach provides a way to obtain fast and robust results, which take into account all the phenomena inherent to compressible unsteady flows. Recently the potential of this method has been explored by incorporating it in a GT-Power model to produce a coupled frequency - time domain simulation of a naturally aspirated engine. The method exhibited promising results. One strategy utilized to combat the increasingly stringent emissions standards and reduce fuel consumption is to employ downsized turbocharged engines equipped with charge air coolers (CAC). Therefore, research and development must focus not only on naturally aspirated engines but also on turbocharged ones.