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The automobile industry and its growing commitment to the environment have collaborated in the development of technologies to reduce emissions of gaseous pollutants, including hydrocarbons. Recent works are aimed at the development of the torch ignition in internal combustion engines of the Otto cycle. A prototype characterized by a torch ignition system with fixed geometry of pre-chamber per cylinder, with a volume of 3.66 cm3 and a single nozzle with a diameter of 6.00 mm, fed with homogeneous mixture originating from Combustion chamber. The ignition and injection system was controlled by a reprogrammable electronic management system. The main results were an increase of around 10% in thermal efficiency and reductions of up to 91% in carbon monoxide emissions, but there was a considerable increase in total hydrocarbons (THC) emissions.

The analysis of engine’s performance, gas emissions and combustion parameters is critical in the development of internal combustion engines. The combustion parameters analysis provide important information to speed up real-time engine’s operation in order to shorter the process of engine’s map calibration. The real-time analysis of these parameters allows the detection of anomalies, such as the prediction of knocking event. From the measurement of the In-cylinder pressure curve and the use of a one-zone combustion model is possible to evaluate the heat release rate, mass burned fraction and average In-cylinder gas temperature. Aiming to expand the amount of real-time data available, such as unburned and burned gases temperature and volume, radius and velocity of turbulent spherical flame and turbulence factor, this paper presents a hybrid combustion model, being composed by coupling a two-zone model to a one-zone model.

The paper describes the setup of a 4-cylinder 1.4-liter prototype Spark Ignited (SI)-engine, which is highly boosted, extremely downsized and port fuel injected. During experimental data gathering with the engine it was discovered that the originally mounted fuel injectors were non-optimized an unable to produce an expected low fuel consumption performance at low speed, low load engine working conditions. To solve this problem by finding an optimized alternative solution for the mixture preparation process it was decided to use a high-performance numerical simulation tool. The paper presents the overall layout of the prototype engine as well as the structure of the 3-D dynamic optimization tool used to address the mixture preparation problem. The paper continues with a detailed description of the different steps used to reach the complete optimization of the mixture preparation system (both the fuel injectors and the intake manifold).