Investigation of oxides of nitrogen emissions from biodiesel-fueled engines

Impact of biodiesel application at various blending ratios on passenger cars of different fueling technologies

“…Biodiesel has a higher bulk modulus of compressibility (or speed of sound) than diesel and this may cause a more rapid transfer of the fuel pump pressure wave to the injector needle. This causes an earlier needle lift and a small advance in injection timing which is proposed to account for a fraction of the NO x increase observed under some conditions [5,10,25]. The bulk modulus effect appears to be present to pump-line nozzle and UI systems, but not to CR systems where a rapid transfer of a pressure wave does not occur [32].…”

“…Reasons for the NO x increase with use of biodiesel have been reviewed by Ban Weiss et al [23,24] and Lapuerta et al [25]. These include an undesirable advance of injection timing due to the varied physical properties of biodiesel (viscosity, density, compressibility, sound velocity) which leads to earlier combustion and higher in-cylinder temperatures [5,10]. Higher flame temperatures may also be caused due to the different combustion chemistry of biodiesel and the decrease in flame radiation due to lower soot formation [23,24].…”

“…In general, biodiesel has a lower heating value and higher natural cetane value, viscosity and density than fossil diesel [3,4]. As a result of the different physicochemical character, biodiesel has been found to affect emissions of diesel engines [5][6][7][8][9][10]. In general, particulate matter (PM), carbon monoxide (CO) and unburned hydrocarbons (HCs) seem to decrease with use of biodiesel.…”

Oxides of nitrogen emissions from biodiesel-fuelled diesel engines

“…Low viscosity results in increased fuel leakage, which causes a decreased rate of pressure rise and thus delays start of injection [33]. Shown in Table 2, biodiesel has a higher viscosity which results in less leakage and contributes to a higher rate of pressure rise (and thus an earlier start of injection) [73].…”

Reduction of NOx in the exhaust gas of DI- diesel engine fueled with mahua methyl ester along with exhaust gas recirculation

“…Charge, which burns early in the combustion process, is especially important since it is compressed to higher temperature and it is caused for the increase in the NO formation rate as combustion proceeds and cylinder pressure increases. 5,6 After reaching the peak pressure, burned gas temperature decreases as the cylinder gases expanded. Due to the sudden decrease in pressure and temperature because of expansion, the reactions involve in the formation of NO x freezes.…”