243 research outputs found
Vlachos (Theodoros N.), Die Geschichte der Byzantinischen Stadt Melenikon
No full textFailler Albert. Vlachos (Theodoros N.), Die Geschichte der Byzantinischen Stadt Melenikon. In: Revue des études byzantines, tome 29, 1971. p. 352
Vlachos (Theodoros N.), Die Geschichte der Byzantinischen Stadt Melenikon
No full textFailler Albert. Vlachos (Theodoros N.), Die Geschichte der Byzantinischen Stadt Melenikon. In: Revue des études byzantines, tome 29, 1971. p. 352
75. Vlachos (Theodoros N.). Die Geschichte der byzantinischen Stadt Melenikon
No full textGouillard Jean. 75. Vlachos (Theodoros N.). Die Geschichte der byzantinischen Stadt Melenikon. In: Revue des Études Grecques, tome 84, fascicule 399-400, Janvier-juin 1971. pp. 264-265
EXPERIMENTAL INVESTIGATION ON PERFORMANCE AND EMISSIONS OF AN AUTOMOTIVE DIESEL ENGINE FUELLED WITH BIOFUELS
No full textBiodiesel is the biofuel most commonly used in Europe, covering approximately 80% of the biofuel market. However, the relationship between biofuel industry and food prices push towards the adoption of new generation biodiesels which could minimize the impact of biofuels production on human food chain. Biodiesel sourced from non-edible seed oils like Jatropha Curcas could therefore be a viable solution for biodiesel production, since allows green cover to wasteland. More recently, also Hydrotreated Vegetable Oil (HVO), obtained by means of a refinery-based process that converts vegetable oils into paraffinic hydrocarbons, has been gaining an increasing attention. The effects of using high percentage blends of ultra low sulphur diesel and biofuels (FAME and HVO) in a Euro 5 small displacement passenger car diesel engine on combustion process, full load performance and part load emissions have been evaluated in this work. Moreover, a characterization of Particulate Matter (PM) in terms of mass, chemical composition and particles number and size distribution was assessed as well. The impacts that fuels with different physical and chemical properties may have on injection, combustion and on ECU calibration process were evaluated by means of specific tests campaign involving different injection timings under part load operation. Results highlighted that the implementation of models for blending detection, on engines ECUs, could be of crucial importance for a wider usage of biofuels in transportation sector. In addition, the effects on engine torque were analyzed, for both a standard ECU calibration (i.e. without any special tuning for the different fuel characteristics) and for a specifically adjusted ECU calibration obtained by properly increasing the injected fuel quantities to compensate for the lower Lower Heating Value (LHV) of the biofuels: with the latter, the same torque levels measured under diesel operation could be observed with the biodiesel too, with lower smoke levels, thus highlighting the potential for maintaining the same level of performance while achieving substantial emissions benefits. Moreover, the effects of biodiesel blends on brake specific fuel consumption and on engine-out exhaust emissions (CO2, CO, HC, NOx and smoke) were also evaluated at several part load operating conditions, representative of the New European Driving Cycle (NEDC). Both standard and specific calibrations were evaluated, highlighting an average rise of fuel consumption in good agreement with LHV decrease, at same fuel conversion efficiency and CO2 emissions. A decrease of NOx emissions when using a specifically adjusted engine calibration, along with a considerable smoke emission reduction were observed as well. Due to increasing concerns about the hazardous effects that particulate matter could have on human health, PM emissions were evaluated under normal engine operating mode at part load operation. PM gravimetric analysis at medium and high load operating points showed a good correlation with soot measurements carried out by means of standard laboratory equipment (i.e. smokemeters). On the contrary, at low loads, the same instrument underestimated the Soluble Organic Fraction (SOF) fraction of PM especially when biofuel was used. Thermo-gravimetric analysis confirmed the outcomes from gravimetric analysis: the significance of standard measurements which are commonly carried out during the engine calibration activity should be carefully considered when biofuels are adopted. Finally, the assessment of the toxicological potential of PM when HVO and Rapeseed Methyl Ester (RME) were used was carried out. Results highlighted that PM from HVO had a higher mutagenic effect respect to PM emissions obtained with other fuel
Effects of Rapeseed and Jatropha Methyl Ester on Performance and Emissions of a Euro 5 Small Displacement Automotive Diesel Engine
No full textThe effects of using neat and blended (30% vol.) biodiesel,
obtained from Rapeseed Methyl Ester (RME) and Jatropha
Methyl Ester (JME), in a Euro 5 small displacement
passenger car diesel engine have been evaluated in this paper.
The impact of biodiesel usage on engine performance at full
load was analyzed for a specifically adjusted ECU
calibration: the same torque levels measured under Diesel
operation could be obtained, with lower smoke levels, thus
highlighting the potential for maintaining the same level of
performance while achieving substantial emissions benefits.
In addition, the effects of biodiesel blends on brake specific
fuel consumption and on engine-out exhaust emissions (CO2,
CO, HC, NOx and smoke) were also evaluated at 6 different
part load operating conditions, representative of the New
European Driving Cycle. Emissions were also measured at
the DPF outlet, thus providing information about aftertreatment
devices efficiencies with biodiesel. The application
of a specifically adjusted engine calibration showed a rise of
fuel consumption, due to the lower energy content of
biodiesel, at same fuel conversion efficiency and comparable
CO2 emissions. An appreciable increase of CO and HC
emissions at low load could be noticed, along with a
considerable smoke emission reduction.
Finally, soot-NOx trade-off were also analyzed for three
different engine operating points, in order to gather detailed
information about further possible emissions benefits that
could be achieved through a more extensive ECU
recalibration
Performance and emissions of a Euro5 small diesel engine fuelled with biodiesel
No full textThis article describes the effects of using neat biodiesel on a modern small displacement passenger car diesel engine, highlighting the need for a specific adjusted electronic control unit (ECU) calibration for biodiesel. Engine performance were evaluated at full load with a standard ECU calibration as
well as with an ECU calibration specifically adjusted for biodiesel; Break Specific Fuel Consumption (BSFC) and exhaust emissions was then evaluated at seven part load operating conditions, representative of the New European Driving Cycle (NEDC). Tests showed that through recalibration it is possible to obtain the same performance measured under diesel operation, with benefits in
terms of engine-out emissions, especially as far as smoke emissions are concerned. Moreover, particle number and size distribution at engine outlet were also evaluated at part load operating conditions, showing a significant reduction of particle number and mass with biodiesel
Analysis of Performance and Emissions of an Automotive Euro 5 Diesel Engine Fuelled with B30 from RME and JME
No full textThe effects of using a B30 blend of ultra low sulphur diesel and two different Fatty Acid Methyl Esters (FAME) obtained from both Rapeseed Methyl Ester (RME) and Jatropha Methyl Ester (JME) in a Euro 5 small displacement passenger car diesel engine on both full load performance and part load emissions have been evaluated in this paper. In particular the effects on engine torque were firstly analyzed, for both a standard ECU calibration (i.e. without any special tuning for the different fuel characteristics) and for a specifically adjusted ECU calibration obtained by properly increasing the injected fuel quantities to compensate for the lower LHV of the B30: with the latter, the same torque levels measured under diesel operation could be observed with the B30 blend too, with lower smoke levels, thus highlighting the potential for maintaining the same level of performance while achieving substantial emissions benefits. Moreover, the effects of the two different 30% vol. blends on brake specific fuel consumption and on engine-out exhaust emissions (CO2, CO, HC, NOx and smoke) were also evaluated at 6 different part load operating conditions, representative of the New European Driving Cycle. Both standard engine calibration (change of the accelerator pedal position) and specifically adjusted engine calibration (adjustment of the energizing time of main injection) were evaluated for part load operating conditions, highlighting a 4% average rise of fuel consumption, on a mass basis, at same fuel conversion efficiency and CO2 emissions. A noticeable increase of CO and HC emissions at low load could also be noticed, along with a significant NOx emissions decrease when using a specifically adjusted engine calibration, and a considerable smoke emission reductio
Particle Number, Size and Mass Emissions of Different Biodiesel Blends Versus ULSD from a Small Displacement Automotive Diesel Engine
No full textA kinetic approach for the estimation of intracellular concentrations of nitrosative species in cells challenged by nitric oxide
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references.by Vasileios Theodoros Dendroulakis.Ph.D
Influence on the performance and emissions of an automotive Euro 5 diesel engine fueled with F30 from Farnesane
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