One approach to enhancing the thermal efficiency of combustion systems is burn fuels at ultra-lean conditions (equivalence ratio below 0.5). It has been recently reported that auto-ignition some hydrocarbon fuels, under specific temperature, pressure, and mixture conditions, releases heat in three distinctive stages. The stages can be divided as a first low-temperature stage with conventional l...

The issue of spontaneous ignition of highly pressurized hydrogen release is of important safety concern, e.g. in the assessment of safety risk and design of safety measures. This paper reports on recent numerical investigation of this phenomenon through releases via a tube using a 5-order WENO scheme. A mixture-averaged multi-component approach was used for accurate calculation of molecular tra...

The reduction of pollutant emissions from internal combustion engines, and in particular greenhouse gases, must be achieved by optimizing the process choosing fuels with a low carbon impact. Heterogeneous mixture combustions such as Diesel induce difficulty managing pollutants formation even if its principle output efficiency remains favorable. Therefore, it is necessary to distinguish this las...

Diethyl ether (DEE) is an interesting species for combustion at least two reasons: On the one hand, it used as a kind of ”worst case” reference substance studies concerned with prevention accidental ignition events. other also candidate bio-fuel. For this reason, in work, auto-ignition different /DEE-mixtures (90/10 and 95/5 mol-% /DEE) are studied rapid compression machine (RCM). In RCM, gas m...

Simulations of forced ignition in a non-premixed laminar counterflow are used to study the effect of the strain rate on ignition success. A one dimensional calculation is performed, using detailed methane chemical kinetics, and treating the ignition event as an instantaneous heat release. Ignition success is seen to depend on the mixture composition and spark location, resulting in lean and ric...

Homogenous Charge Compression Ignition (HCCI) is a mode of combustion in IC engines in which premixed fuel and air are ignited spontaneously. There is a belief that HCCI engines have a great potential to improve fuel consumption and reduce NOx emissions. In this study, a single zone, zero dimensional, thermo-kinetic model has been developed and a computer program with MATLAB software is use...

Using the G-Scheme, we have developed a specific procedure to generate simplified mechanisms for chemical kinetics processes, to analyze them in order to understand the role of the most important reactions, and to identify the most important reactions paths of the processes. The procedure is based on participation indices specifically created for a GScheme generated database. The effectiveness ...