When looking at the effects of diesel engine exhaust on the environment, it is important to first look at the composition of the exhaust gases. Over 99.5% of the exhaust gases are a  combination of  nitrogen, oxygen, carbon dioxide, and water. With the exception of carbon  dioxide, which contributes about  5% of the total volume, the diesel engine exhaust consists of  elements which are part of...

as motorcycles are named as one of the important air pollution emission sources in tehran, investigating their emission performance and finding a solution for reducing their emission is of high importance. in this study, emission factors from 60 motorcycles from tehran’s present fleet and 4 closed loop injection fuel supply system and catalytic converter equipped motorcycles were measured. meas...

in this paper, a numerical study is performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (rcci) combustion mode in a heavy-duty, single-cylinder diesel engine with gasoline and diesel fuels. in rcci strategy in-cylinder fuel blending is used to develop fuel reactivity gradients in the combustion chamber that result in a ...

Coal combustion is the primary anthropogenic source of atmospheric iodine, which has important environmental and health effects. The iodine distribution in Chinese coals and the atmospheric iodine emission factors of coal-fired boilers are studied to estimate the iodine atmospheric flux from coal combustion in China from 1995 to 2009. The national average iodine content weighted by coal yield f...

this study investigated different concepts for natural-gas-fired power plants with the co2capture, and compared them based on the net plant efficiency and emission of co2. the cycles were based ona six oxy-fuel, one post-combustion and two pre-combustion capture concept. this paper presented theresults of an environmental evaluation performed by the application of the life cycle analysis (lca) ...

Diesel engines are the most commonly used internal combustion engines nowadays, especially in European transportation. This preference is due to their low consumption and acceptable driveability and comfort. However, the main disadvantages of traditional direct injection Diesel engines are their high levels of noise, nitrogen oxides (NO x) and soot emissions, and the usage of fossil fuels. In o...

The development of combustion systems to minimize the emission of pollutants and to increase the system’s efficiency involves modifications of the combustion process using premixed systems and highly turbulent swirl stabilized flames. However, these modifications of the combustion process usually lead to stability problems caused by the appearance of combustion-driven oscillations. Therefore, i...

In this study, a 3D combustion chamber was simulated using FLUENT 6.32. Aim to obtain detailed information on combustion characteristics and _ nitrogen oxides in the furnace and the effect of oxygen enrichment in a combustion process. Oxygenenriched combustion is an effective way to reduce emissions. This paper analyzes NO emission, including thermal NO and prompt NO. Flow rate ratio of air to ...

A detailed chemistry-based CFD model was developed to simulate the diesel spray combustion and emission process. A reaction mechanism of n-heptane is coupled with a reduced NOx mechanism to simulate diesel fuel oxidation and NOx formation. The soot emission process is simulated by a phenomenological soot model that uses a competing formation and oxidation rate formulation. The model is applied ...

Ways to reduce nitrogen oxide emissions In order to comply with the increasingly tough emission standards worldwide, engine manufacturers are forced not only to substantially reduce emissions of particulate matter (PM), but also emissions of nitrogen oxides. The main approach pursued by MTU is low-emission combustion, in other words an internal engine solution. However, this means taking into a...