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Engine models are a basis for better controlling combustion process and the exhaust emissions resulting from it. Currently the zero- and quasi-dimensional models are mostly used. These types of models are also addressed in this article. Zero-dimensional models are computationally efficient and show good simulation results concerning the in-cylinder pressure. However, by neglecting multi-zonal resolution they are not able to describe fuel efficiency or the generation of pollutants. It is therefore necessary to enhance combustion process models with phenomenological fuel spray and vaporization models, with a local resolution of at least two zones. The chemical model for the calculating of emissions shall be based on a two-zone model. The amount of mass, which is transferred from the unburned to the burned zone, is entered into a chemical model based on the chemical equilibrium for the OCH-system (oxygen/carbon/hydrogen).

In the last decade direct injecting diesel engines have become more and more important in the automobile industry. Common-rail systems allow to shape the injection curve to reduce emissions, to get a better fuel economy and to provide more comfort. For this the common-rail system itself must be improved. A fundamental problem of the common-rail technology is to measure the exact injected amount of fuel, depending on the absolute rail pressure and pressure oscillations on the rail. Another problem is the delay between trigger signal of the injector and opening of the injector that results in a non-smooth idle speed. One idea to solve this problem is to install a pressure sensor in front of the injector. Due to costs and density problems under high pressure, a simple, non-invasive sensor is preferred. The sensor introduced in this paper is based on the magneto-elastic effect and does not involve any mechanical elements.