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A significant share of the emissions of a vehicle with internal combustion engine originates from the cold start. In addition to the more stringent limits for particulate emissions due the introduction of the Euro 6c standard for gasoline engines with direct injection (GDI), exhaust gas emission testing is currently performed applying the real driving emission test procedure (RDE) required by the Euro 6d TEMP standard. The RDE test procedure is not clearly defined, potentially allowing high loads immediately after the engine start. Under such circumstances the combustion chamber features low surface temperatures impairing emission performance and in particular provoking the excessive generation of hydrocarbon and particulate emissions. It is therefore important not only to examine the heating of the catalytic converter during the cold start, but also the preconditioning of the combustion chamber itself.

Steadily rising energy prices and increasingly strict emissions legislation enforce the development of measures that increase efficiency of modern vehicles. An important contribution towards more efficient vehicles is the introduction of measures regarding auxiliary units. These measures increase the gross efficiency of a vehicle and therefore also the vehicle's range. Among the auxiliary power units of a vehicle like a long-haul truck, the refrigerant compressor generally consumes the biggest amount of energy. Therefore, it is reasonable to focus efficiency-increasing efforts on optimizing the A/C system. An important tool used in the development of optimization approaches is the simulation of the relevant systems. This allows a cost-optimized evaluation of the optimization approaches and also lets the engineer compare multiple variations of these approaches within a short period of time.

Rising oil prices and increasing strict emission legislation force vehicle manufacturers to reduce fuel consumption of future vehicles. In order to meet this target, the process of converting fuel into useable energy and the use of this energy by the different energy-consuming vehicle's subsystems have to be examined. Vehicles' subsystems consist of energy-supplying, energy-consuming, and in some cases energy-storing components. Due to the high complexity of these systems and their interaction, optimization of their energy efficiency is a challenging task. By introducing individual operational strategies for each subsystem, it is possible to increase the energy efficiency for a specific function. To further improve the vehicle's overall energy efficiency, holistic control strategies are introduced that distribute the energy between the subsystems intelligently.