Ignition delay and its influence on the performance of a Diesel engine operating with different Diesel–biodiesel fuels

• DOI: 10.1016/j.egyr.2021.08.123
• Publication Date: 2021-09-08T07:20:04Z
• Authors: Lucian Miron; Radu Chiriac; Marek Brabec; Viorel Bădescu
• Keywords: Diesel engine; 13. Climate action; Biofuels; Ignition delay; 0211 other engineering and technologies; Pollutant emissions; Electrical engineering. Electronics. Nuclear engineering; 02 engineering and technology; 7. Clean energy; TK1-9971

The ignition delay is an important parameter which characterizes the initiation of combustion process and consequently its development in Diesel engines. This parameter mainly depends on chemical factors which are related to the fuel structure and its properties and also on physical factors which are related to the engine operating conditions. The need for alternative fuels usage in Diesel engines determined by the depletion of petroleum resources and by the regulations imposed on pollutant emissions have enforced the researches on renewable biofuels. Among these new fuels, biodiesel B7, actually in use, and biodiesel B20, in prospective, have received a particular interest. In this sense, an experimental and theoretical study was performed on a tractor Diesel engine aiming to determine the ignition delay of the rapeseed biodiesel B7 and B20 and to compare them with the ignition delay of pure Diesel fuel for full load and different engine speeds as tested operating conditions. This present study represents an extension of the previously mentioned research having now as objectives: to review what are the methods used for the ignition delay evaluation, to perform a comparison between several commonly Arrhenius type relationships used for the assessment of ignition delay and the ignition delay experimentally determined, and to offer a better understanding of the influences induced by the ignition delay respectively by the fuel reactivity on performance, efficiency and emissions of compression ignited engines operating with different Diesel–biodiesel fuels. The novelty of this work consists in the statistical approach to probability density of ignition delay which leads to better estimation of this crucial parameter and consequently to better control of the combustion process.