Remarkable improvement of NOx–PM trade-off in a diesel engine by means of bioethanol and EGR

Abstract

In order to realize a premixed compression ignition (PCI) engine, the effects of bioethanolgas oil blends and exhaust gas recirculation (EGR) on PM-NOx trade-off have been investigated focusing on ignition delay, premixed combustion, diffusion combustion, smoke, NOx and thermal efficiency. The present experiment was done by increasing the ethanol blend ratio and ethanol and by increasing the EGR ratio in a single cylinder direct injection diesel engine. It is found that a remarkable improvement in NOx-PM trade-off can be achieved by promoting the premixing based on the ethanol blend fuel having low evaporation temperature, large latent heat and low cetane number as well, in addition, based on a marked elongation of ignition delay due to the low cetane number fuel and the low oxygen intake charge. As a result, very low levels of NOx and PM, which satisfies the 2009 emission standards imposed on heavy duty diesel engines in Japan, were achieved without deterioration of brake thermal efficiency in the PCI engine fuelled with the 50% ethanol blend diesel fuel and the high EGR ratio. It is noticed that smoke can be reduced even by increasing the EGR ratio under the highly premixed condition.

Effects of EGR rate on performance and emissions of a diesel power generator fueled by B7

“…Exhaust gas recirculation (EGR), which returns a portion of the engine exhaust gas to the combustion chamber via the intake system, shows a great potential to reduce NO X emissions [2,3]. The application of this technique to spark ignition and compression ignition engines has been studied with regard to its effects on engine performance, inlet air temperature control, combustion control and dual-fuel operation [4][5][6][7][8][9][10][11][12]. The possibility of reducing NO x emissions with the use of EGR rate results from thermal, chemical and dilution effects [8,9,[13][14][15][16].…”

Comparison of Engine Simulation Software for Development of Control System

“…Also, it affects significant improvement of performance such as NOx emission, engine break power, and fuel consumption. In [18], significant improvements were achieved in terms of performance by using 5% of EGR at low.…”

Effects of 2,5-dimethylfuran addition to diesel on soot nanostructures and reactivity

“…Oxygenated fuels such as ethanol [12,13], methanol [14,15], ethers [16,17], ketones [18,19], biodiesel [20,21], and plant-derived oils (e.g. vegetable oil, jatropha oil [22,23] and rapeseed oil [24]), when blended with gasoline or diesel, have been shown in the literature to reduce soot emissions.…”