Impact of Cold and Hot Exhaust Gas Recirculation on Diesel Engine
Today most of the transport vehicles in countries like India where cost effective is the predominant criteria utilize diesel engines rather than petrol engines. From past 5 years usage of diesel engines was rapid which can be addressed from the sales report of many automobile companies. The reason behind this could be cost of diesel fuel and efficiency of the diesel engine when compared to petrol engine. But when we look on the worse side of diesel engine, emissions from diesel engine are high especially NOx. So there is a need for a technique which could reduce the emissions without affecting the performance of engine. One such technique could be Exhaust gas recirculation. Present paper aims to find the impact of cold and hot EGR on emissions of diesel engine.
Control of oxides of nitrogen from diesel engines using diluents while minimising the impact on particulate pollutants
The investigation was conducted on a high-speed direct-injection diesel engine and was concerned with the effects of exhaust gas recirculation (EGR) on diesel engine combustion and emissions. In particular, the effects on combustion and emissions of carbon dioxide (CO2) and water vapour (H2O), principal constituents of EGR, were analysed and quantified experimentally. The effects of increased inlet temperature and thermal throttling of the inlet charge, both arising from the use of hot EGR, were also investigated. Finally, tests were carried out during which the CO2 added to the engine air flow increased the charge mass flow rate to the engine, rather than displacing some of the oxygen (O2) in the inlet air. It was found that when CO2 or H2O displaced O2 in the inlet charge, both the chemical and thermal effects on exhaust emissions were small. However, the dilution effect was substantial, and resulted in very large reductions in exhaust NOx at the expense of higher particulate and unburnt hydrocarbon emissions. Higher inlet charge temperature increased exhaust NOx and particulate emissions, but reduced unburnt hydrocarbon emissions. Reduction in the inlet charge due to thermal throttling reduces NOx emissions but raises all the other pollutants. Finally, when CO2 was additional to the inlet air charge (rather than displacing O2), large reductions in NOx were recorded with little increase in particulate emissions.
The Italian Renaissance: Culture and Society in Italy
In this newly revised edition of his widely acclaimed work, Peter Burke presents a social and cultural history of the Italian Renaissance. He discusses the social and political institutions that existed in Italy during the fifteenth and sixteenth centuries, and he analyzes the ways of thinking and seeing that characterized this period of extraordinary artistic creativity. Developing a distinctive approach, the author is concerned not only with the finished works of Michelangelo, Raphael, Leonardo da Vinci, and others, but also with the social background, patterns of recruitment, and means of subsistence of this "cultural elite." He thus makes a major contribution both to our understanding of the Italian Renaissance and to our comprehension of the complex relations between culture and society. An excellent social history of the lives and culture of the artists and artisans which made it possible for the arts to flourish.