Abstract
Keywords: System Simulation, Thermal Management, Thermal Comfort, Additional Heating, Fuel Consumption, Pollutant Emissions.
One of the current challenges faced by car manufacturers and suppliers is to develop vehicles that are more environmentally friendly and that respect current and future emission regulations. Improved engine efficiency has led to a reduction of heat released into the coolant circuit that renders heating the cabin and ensuring passengers´ comfort increasingly problematic. Demisting and de-icing are also strongly dependent on the availability of a heat sources, in particular during vehicle starting.
To remedy the lack of thermal energy for cabin comfort, more and more vehicles and in particular diesels, are equipped with additional heating devices such as burners or electrical heaters. Figure 1 illustrates this tendency by showing the market shares by engine type and climate for Europe for 2006, the thermal deficit to be compensated and an estimation of vehicles equipped with additional heating. Two-thirds of the new cars will have to be equipped with additional heating devices with a heating power from 0.5 to 2.5 KW in temperate countries and up to 6 KW in cold countries.
At the same time, environmental requirements stipulate a reduction in fuel consumption and emissions, including during the vehicle starting phases, when the engine does not reach its optimal operating mode. However, it is precisely during these phases that additional heating devices are particularly requested. Optimization of these devices therefore becomes essential in the evaluation and the control of the environmental impact of vehicles.