Knocking combustion in spark-ignition engines

http://users.ntua.gr/vgiakms/pdf/PECS_2006.pdf

Second-law analyses applied to internal combustion engines operation

A survey is made of high-temperature membranes and several possible applications of membrane reactors for integration in power generation cycles with CO2 capture. Current performance and limitations of relevant inorganic membranes are presented and discussed. Integrated H2, O2 or CO2 membrane separation is analysed and it is concluded that development of power plant concepts including membrane technology is not yet fully explored. Significant design optimisation would be required in order to identify efficient, feasible and environmentally sound technical solutions. In addition, further development and validation of performance of membranes in real applications are needed.

High-temperature membranes in power generation with CO2 capture

The engine knock analysis – An overview

In order to achieve the required future CO 2 reduction targets significant further development of both gasoline and diesel engines is required. One of the main methods to achieve this with the gasoline engine in the short to medium term is through the application of engine downsizing, which has resulted in numerous downsized engines already being brought to production. It is, however, considered that there is still significant further CO 2 reduction potential through continued development of this technology. This paper considers the future development of gasoline engine downsizing in the short to medium term and the various technologies that can be applied to further increase the efficiency of operation. As such this paper covers, among other areas, fundamental engine layout and design, alternative boosting systems, methods of increasing part load efficiency and vehicle modelling, and uses analysis tools and engine test results to show the benefits achievable.

Challenges for Increased Efficiency through Gasoline Engine Downsizing

Potentials of cooled EGR and water injection for knock resistance and fuel consumption improvements of gasoline engines

The paper is focused on the development of a fractal combustion model, included within a whole-engine one-dimensional model (1 Dime code). An extensive validation is carried out through the comparison with experimental data. The experimental activity was carried out in the combustion chamber of an optically accessible one-cylinder engine, equipped with a commercial head. Experimental data basically consisted on optical measurements which were also correlated to the instantaneous pressure inside the cylinder. Optical measurements were based on 2D digital imaging and UV chemiluminescence of radical species. The rate of chemical energy release and related parameters were evaluated from the in-cylinder pressure data using interpretation models for heat release analysis. Moreover a post-processing of the optical measurements allowed to define the mean flame radius, and propagation speeds as well, as a function of the crank angle. Theoretical and experimental analyses allowed to fully characterize flame structure and propagation speed as well. In order to estimate prediction levels and limitations of the numerical procedure, different engine speeds and spark timings were experimentally analyzed. A good agreement has been found in the whole tested range.

Fabio Bozza

Papers

Potentials of cooled EGR and water injection for knock resistance and fuel consumption improvements of gasoline engines

Validation of a Fractal Combustion Model through Flame Imaging

A Theoretical Comparison of Various VVA Systems for Performance and Emission Improvements of SI-Engines

Experimental and numerical study on the influence of cooled EGR on knock tendency, performance and emissions of a downsized spark-ignition engine

3D-1D Analyses of the Turbulent Flow Field, Burning Speed and Knock Occurrence in a Turbocharged SI Engine