Abstract
Keywords
Heat management, Fuel Consumption, Warm Up Phase, Emissions, Controller
Abstract
The reduction of fuel consumption and exhaust emission poses a major objective in development and research of modern combustion engines. This fact is affirmed by the commitment of the automotive manufacturers in reference to the CO2-emissions. The goal is to decrease the emissions to a value of 120g/km by the year 2012. The emission values for the year 2003 are 170g/km for European manufacturers, 174g/km for Japanese manufacturers, and 160g/km for German manufacturers.
In order to reach this goal, potential for improvements to the cooling system have to be exposed, among other car modifications (lightweight construction, increase of powertrain efficiency, decrease of rolling friction and drag) and improvements of the engine (fuel-mixture generation, combustion and friction). By using heat management, significant savings in fuel consumption are possible, especially during warm up phase and in the part-load operational range of the engine.
Steady state cooling systems control the temperature of the coolant and keep it at certain levels. The heat dissipation is a function of engine speed, but the heat which is generated by the engine is a function of the engine speed and the dominating load value. It is known that the specific fuel consumption decreases with increasing temperature of the engine components and the combustion chamber in particular. Perfection of combustion and reduction of friction losses are major goals. Thermal dethrottling of IC engines contributes to the improvements.
The presented concept uses data from the sensors of a series-production car to create a controller that uses previous conditions and situations to predict a scenario for a subsequent amount of time. It detects different types of drivers and tracks which reflect current and anticipated load ranges and driving conditions, i.e., an estimate of heat which has to be dissipated. The cooling potential can be estimated on the basis of the awaited driving conditions. A comparison of the conditions enables a demand-guided cooling system in order to increase the component temperatures of the engine, especially during warm up phase and in part-load operational range. Thus, fuel consumption and exhaust emissions could be reduced.