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Viewing 31 to 60 of 22875
2015-09-06
Technical Paper
2015-24-2514
Marco Piumetti, Samir Bensaid, Nunzio Russo
A set of ceria-zirconia nanocatalysts with different Zr-contents and structural properties was prepared to study the effect of both the Zr-amount and surface-dependent activity towards soot combustion in “loose” and “tight” soot-catalyst contact. The properties of the catalysts were examined using several physico-chemical techniques. The best soot oxidation activities were achieved for the Ce0.9Zr0.1O2-NP catalyst (NP means nano-polyhedra and 0.9 indicates the atomic ratio of Ce/Ce+Zr), due to its easier reducibility, compared to high-surface area catalysts with the same Ce/Zr ratio. Moreover, better performances were reached for Ce0.9Zr0.1O2-NP, than similar nano-polyhedra with higher Zr-amounts (denoted as CexZr1-xO2-NP, where x = 0.8 or 0.7). On the other hand, worse activities were obtained for both mesoporous and microporous catalysts with the same Ce/Zr ratio.
2015-09-06
Technical Paper
2015-24-2518
Riccardo Amirante, Elia Distaso, Paolo Tamburrano, Rolf D. Reitz
Due to the new challenge of meeting number-based regulations for particulate matter (PM), a numerical and experimental study has been conducted to better understand particulate formation in engines fuelled with compressed natural gas. The study has been conducted on a Heavy-Duty, Euro VI, 4-cylinder, spark ignited engine, with multipoint sequential phased injection and stoichiometric combustion. For the experimental measurements two different instruments were used: a condensation particle counter (CPC) and a fast-response particle size spectrometer (DMS) the latter able also to provide a particle size distribution of the measured particles in the range from 5 to 1000 nm. Experimental measurements in both stationary and transient conditions were carried out. The data using the World Harmonized Transient Cycle (WHTC) were useful to detect which operating conditions lead to high numbers of particles. Then a further transient test was used for a more detailed and deeper analysis.
2015-09-06
Technical Paper
2015-24-2515
Christophe Barro, Sushant Pandurangi, Philipp Meyer, Konstantinos Boulouchos, Philipp Elbert, Yuri M. Wright
Abstract Past research has shown that post injections have the potential to reduce Diesel engine exhaust PM concentration without any significant influence in NOx emissions. However, an accurate, widely applicable rule of how to parameterize a post injection such that it provides a maximum reduction of PM emissions does not exist. Moreover, the underlying mechanisms are not thoroughly understood. In past research, the underlying mechanisms have been investigated in engine experiments, in constant volume chambers and also using detailed 3D CFD-CMC simulations. It has been observed that soot reduction due to a post injection is mainly due to two reasons: increased turbulence from the post injection during soot oxidation and lower soot formation due to lower amount of fuel in the main combustion at similar load conditions. Those studies do not show a significant temperature rise caused by the post injection.
2015-09-06
Technical Paper
2015-24-2501
Thomas Laible, Stefan Pischinger, Bastian Holderbaum
Abstract Within a project of the Research Association for Combustion Engines e.V., different measures for rising the temperature of exhaust gas aftertreatment components of both a passenger car and an industrial/commercial vehicle engine were investigated on a test bench as well as in simulation. With the passenger car diesel engine and different catalyst configurations, the potential of internal and external heating measures was evaluated. The configuration consisting of a NOx storage catalyst (NSC) and a diesel particulate filter (DPF) illustrates the potential of an electrically heated NSC. The exhaust aftertreatment system consisting of a diesel oxidation catalyst (DOC) and a DPF shows in simulation how variable valve timing in combination with electric heated DOC can be used to increase the exhaust gas temperature and thus fulfill the EU6 emission limits.
2015-09-06
Technical Paper
2015-24-2504
Gerben Doornbos, Emma Adams, Per-Anders Carlsson, Daniel Dahl, Mats Laurell, Håkan Schyllander, Par Gabrielsson, Milica Folic, Ingemar Denbratt, Magnus Skoglundh
Commercial three way catalysts have limited capacity towards reducing NOx in the presence of excessive oxygen. This prevents lean-burn combustion concepts from meeting legislative emission standards. A solution towards decreasing NOx emissions in the presence of excess air is the use of a passive-SCR system. Under rich conditions ammonia is formed over an ammonia formation catalyst, the ammonia is stored in the SCR and in its turn reacts with the NOx under lean engine conditions. Here up-scaled Pt/Al2O3 and Pd/Al2O3 catalysts as well as a commercially Pd-Rh based three-way catalyst (TWC) are evaluated using both engine and further lab-scale tests. The purpose of these tests is to compare the ammonia production for the various catalysts under various lambda values and temperatures by means of engine and lab scale tests. The Pd/Al2O3 showed little sensitivity to temperature both under engine and lab scale experiments.
2015-09-06
Technical Paper
2015-24-2482
Wolfgang Mühlbauer, Sebastian Lorenz, Dieter Brueggemann
Finite fossil energy sources and carbon dioxide as a main cause for climate changes are still under critical discussion. Therefore, scientists work on the replacement of fossil by alternative diesel fuels from biomass. Hence, in this study the in-cylinder combustion and particle number emissions of di-n-butyl ether (DNBE), as a representative of second generation biofuels, and of reference diesel fuel (B0) for comparison were analyzed by several measurement techniques at different injection and boost pressures. The heat release rate and thus the ignition delay as well as the center of combustion were analyzed by monitoring the global in-cylinder pressure signal using a pressure sensor. The combustion process was also visualized by simultaneous imaging of the hydroxyl radical and a spectral range of soot luminescence. This allows the analysis of the in-cylinder soot formation and oxidation process.
2015-09-06
Technical Paper
2015-24-2485
Tamara Ottenwaelder, Thomas Raffius, Christian Schulz, Philipp Adomeit, Gerd Grunefeld, Stefan Pischinger
Abstract In order to reduce engine out CO2 emissions it is a main subject to find new alternative fuels out of renewable sources. For this reason in this paper a blend out of 1-octanol and di-n-butylether and pure di-n-butylether are investigated in comparison to n-heptane as diesel-like fuel. The alternative fuels have a different combustion behavior particularly concerning important combustion parameters like ignition delay and mixture formation. Especially the formation of pollutants like nitrogen oxides in the combustion of alternative fuels is of global interest. The knowledge of the combustion behavior is important to design new engine geometries or implement a new calibration of the engine. In previous measurements in a single cylinder engine it was found out that both alternative fuels form nearly no soot emissions. For this reason now NOx is investigated optically to avoid the traditional soot NOx trade-off in diesel combustion.
2015-09-06
Technical Paper
2015-24-2488
Martin Pechout, Ales Dittrich, Martin Mazac, Michal Vojtisek-Lom
Abstract Butanol, which can be produced from biomass, has been suggested as an alternative to ethanol, due to its higher energy density, lower oxygen content and more favorable hygroscopic and corrosive properties. In the Czech Republic, E85 is widely sold at fuel stations and used in ordinary vehicles, both with and without aftermarket control units. This work investigates the potential of ordinary automobiles to run on butanol, and the associated effects on exhaust emissions under real driving conditions. A Škoda Felicia car with a throttle body injection and a Škoda Fabia car with a multi-point port injection have been run on gasoline and its mixtures with up to 85% volume of ethanol, of n-butanol, and of isobutanol (2-methyl-1-propanol). An auxiliary control unit has been used with higher alcohol content. On each fuel, each car was driven 5-6 times along a local test route.
2015-09-06
Technical Paper
2015-24-2490
Francesco Catapano, Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco
Abstract Ethanol is the most promising alternative fuel for spark ignition (SI) engines, that is blended with gasoline, typically. Moreover, in the last years great attention is paid to the dual fueling, ethanol and gasoline are injected simultaneously. This paper aims to analyze the better methods, blending or dual fueling in order to best exploit the potential of ethanol in improving engine performance and reducing pollutant emissions. The experimental activity was carried out in a small displacement single cylinder engine, representative of 2-3 wheel vehicle engines or of 3-4 cylinder small displacement automotive engines. It was equipped with a prototype gasoline direct injection (GDI) head. The tests were carried out at 3000, 4000, and 5000 rpm full load. The investigated engine operating conditions are representative of the European homologation urban driving cycle.
2015-09-06
Technical Paper
2015-24-2500
Nic van Vuuren, Gabriele Brizi, Giacomo Buitoni, Lucio Postrioti, Carmine Ungaro
One of the favored automotive exhaust aftertreatment solutions used for nitrogen oxides (NOx) emissions reductions is referred to as Selective Catalytic Reduction (SCR), which comprises a catalyst that facilitates the reactions of ammonia (NH3) with the exhaust nitrogen oxides (NOx). It is customary with these systems to generate the NH3 by injecting a liquid aqueous urea solution (AUS-32) into the exhaust. The urea solution is injected into the exhaust and transformed to NH3 by various mechanisms for the SCR reactions. Understanding the spray performance of the AUS-32 injector is critical to proper optimization of the SCR injection system. Results were previously presented from imaging of an AUS-32 injector spray under hot exhaust conditions at the injector spray exit for an exhaust injection application.
2015-09-06
Technical Paper
2015-24-2503
Philippe Moreau, Patricia Valero, Valerie Tschamber, Alain Brillard, Jean-Francois Brilhac, Yves Hohl, Regis Vonarb
Abstract The aim of the study is to evaluate the possible vanadium emissions from different commercially available vanadium-based SCR monoliths. The vanadium sublimation was studied at laboratory scale using a monolith sample (16 mm diameter × 19 mm long). Vanadia vapors were disposed on an alumina bed placed downstream the catalyst sample, in the hot zone of a furnace. Experiments were carried out with a space velocity of 42 000 h−1. The reactive gas flow was composed of 5%O2, 5%H2O, 500ppm NO and 500ppm NH3. Catalyst samples and alumina bed were exposed to this reactive gas flow during 10 hours at 500°C, 600°C, 650°C, 675°C, 700°C and 750°C, successively. After each test, alumina samples were mineralized from HNO3, HF and HCl mixture. The digests were then diluted with high purity water prior, to ICP-MS analysis. The results revealed that, for full body type catalysts, sublimation of vanadium increases in a significant way from an exposure to the reactive gas flow at 675°C.
2015-09-06
Technical Paper
2015-24-2509
Maria Vittoria Prati, Giovanni Meccariello, Livia Della Ragione, Maria Antonietta Costagliola
The aim of this study is to investigate the parameters influencing the real driving emission monitoring with particular attention towards the influence of road gradient. For this purpose, an experimental activity was carried out with a Euro 5 Diesel light-duty vehicle, driven along two tracks of Naples characterized by a different road gradient: the first pattern is quite flat, the second includes positive (+2.9%) and negative (−3.6%) road gradient. Exhaust emissions of CO, THC, NOx, CO2 were acquired on road by using a portable emission measuring system (PEMS) connected also to the Engine Control Unit for saving the main engine parameters and to the GPS for the geographical coordinates and altitude. The acquired speed profiles were repeated on the chassis-dynamometer without simulating the road gradient.
2015-09-06
Technical Paper
2015-24-2505
Maria Rosaria Gaballo, Maria Giodice, Alberto Diano, Fabio Fersini, Francesco Miccolis, Soenke Mannal, Stefan Motz
Abstract The world of diesel is becoming more technically complex due to the increasingly restrictive legislation regarding emissions, fuel consumption, and real driving emissions evaluations (RDE). Simulation provides a mechanism for the investigation and optimization of diesel engine performance, new engine concepts, RDE, and after-treatment design. This can contribute to solve the problems that the restrictive legislation creates. In addition to these generally valid capabilities of simulations, our model development is focused on the mission to use correctly sized models to reduce the usage of resources and make simulation an even more rapid and cost effective method. In this contribution, we present our approach for simulation as an advanced integrated tool capable of answering challenging questions presented by emission and fuel consumption reduction in future legislation frameworks.
2015-09-06
Technical Paper
2015-24-2506
Paolo Iodice, Adolfo Senatore
Nowadays, due to catalyst improvements and electronic mixture control of last generation vehicles equipped with internal combustion engine, the most significant part of the total emissions of carbon monoxide and unburned hydrocarbons takes place during the cold phase, if compared with those exhausted in hot conditions, with a clear consequence on air quality of urban contexts. The purpose of this research, developed by the Department of Industrial Engineering of the University of Naples Federico II with reference to an European background, is a deeper analysis of the engine and after-treatment system behaviour within the cold start transient and the evaluation of cold start additional emissions: a methodology was developed and optimized to evaluate the cold transient duration, the emitted quantities during the cold phase and the relevant time-dependence function.
2015-09-06
Technical Paper
2015-24-2448
Mengqin Shen, Vilhelm Malmborg, Yann Gallo, Bjorn B. O. Waldheim, Patrik Nilsson, Axel Eriksson, Joakim Pagels, Oivind Andersson, Bengt Johansson
Abstract When applying high amount of EGR (exhaust gas recirculation) in Partially Premixed Combustion (PPC) using diesel fuel, an increase in soot emission is observed as a penalty. To better understand how EGR affects soot particles in the cylinder, a fast gas sampling technique was used to draw gas samples directly out of the combustion chamber in a Scania D13 heavy duty diesel engine. The samples were characterized on-line using a scanning mobility particle sizer for soot size distributions and an aethalometer for black carbon (soot) mass concentrations. Three EGR rates, 0%, 56% and 64% were applied in the study. It was found that EGR reduces both the soot formation rate and the soot oxidation rate, due to lower flame temperature and a lower availability of oxidizing agents. With higher EGR rates, the peak soot mass concentration decreased. However, the oxidation rate was reduced even more.
2015-09-06
Technical Paper
2015-24-2510
Jan Czerwinski, Pierre Comte, Martin Güdel, Andreas Mayer, Jacques Lemaire, Felix Reutimann, Adm Heinz Berger
Abstract As a result of increased use of catalytic exhaust aftertreatment systems of vehicles and the low-sulfur Diesel fuels there is an increasing share of nitrogen dioxide NO2 in the ambient air of several cities. This is in spite of lowering the summary nitric oxides NOx emissions from vehicles. NO2 is much more toxic than nitrogen monoxide NO and it will be specially considered in the next legal testing procedures. There are doubts about the accuracy of analyzing the reactive substances from diluted gas and this project has the objective to show how NO2 is changing as it travels down through the exhaust- and the CVS systems. For legal measurements of NO2 a WLTP-DTP subgroup (Worldwide Light Duty Test Procedures - Diesel Test Procedures) proposed different combinations of NOx-analyzers and analysis of NO and NOx. Some of these set-ups were tested in this work.
2015-09-06
Technical Paper
2015-24-2517
Piotr Bielaczyc, Joseph Woodburn, Andrzej Szczotka
Abstract Particulate matter in vehicular exhaust is now under great scrutiny. In the EU, direct injection spark ignition (DISI) engines running on petrol now have limits for particulate emissions set for both mass and number. Current legislative test procedures represent a best-case scenario - more aggressive driving cycles and lower ambient temperatures can increase particulate emissions massively. Ambient temperature is generally the environmental parameter of most importance regarding particulate emissions from an engine, particularly for the reasonably brief periods of operation typical for passenger cars operating from a cold start. Two Euro 5 vehicles with DI SI engines were laboratory tested at three ambient temperatures on two different commercially available fuels, with particulate emissions results compared to results from the same fuels when the vehicles were tested at 25°C.
2015-09-06
Technical Paper
2015-24-2440
Dávid Kovács, Peter Eilts
Abstract A variable air path on diesel engines offers further potentials to manage the challenges of engine development - such as reduction of emissions and fuel consumption, as well as performance increase. The Miller cycle is one of the possibilities, which is well known as an effective way to reduce process temperatures and so NOX emissions. The present paper discusses the potentials of this strategy for heavy duty diesel engines by identifying and analyzing the effects caused. The investigations were carried out in the upper load range. First the isolated effect of the Miller cycle was analyzed. The results show reduced NOX emissions, although increased PM and CO emissions were measured. Further, the Miller cycle caused a reduction in peak cylinder pressure. This pressure reserve can be used to combine the Miller cycle with further measures while maintaining the maximum cylinder pressure of the reference operation point.
2015-09-06
Technical Paper
2015-24-2441
Robert Morgan, Andrew Banks, Andrew Auld, Morgan Heikal, Christopher lenartowicz
Abstract Diesel fuel injection pressures have increased steadily on heavy duty engines over the last twenty years and pressures as high as 300MPa are now possible. This was driven by the need to control toxic exhaust emissions, in particular particulate emissions using advanced in-cylinder combustion strategies. With the introduction of efficient aftertreatment systems for both particulate and NOx emissions control there is less demand for in-cylinder emissions control especially considering the drive for improved fuel economy. In this paper we consider the benefit of high fuel injection pressure for a number of emissions control strategies with different balances of in-cylinder and exhaust aftertreatment emissions control. A test program was undertaken on a single cylinder heavy duty research engine installed at the University of Brighton, in collaboration with Ricardo.
2015-09-06
Technical Paper
2015-24-2445
Carlo Beatrice, Gabriele Di Blasio, Ezio Mancaruso, Luigi Sequino, Bianca Maria Vaglieco
Abstract In this paper, a detailed analysis of combustion and emissions is carried out on both metal and optical light duty diesel engines equipped with up-to-date combustion architecture. Both engines were fed with glycerol ethers mixture (GEM) in blend (10% and 20% v/v) within a commercial diesel fuel. The engines ran in significant operating points in the NEDC (New European Driving Cycle) emission homologation area. The results of the experimental campaign on the metal engine show comparable performances between the diesel/GEM blends and the diesel fuel and demonstrate benefits mainly in terms of soot production. The exhaust particles diameters of diesel/GEM blends shift toward smaller dimensions and the total number decreases. Moreover, at lower load conditions, the outputs show a worsening of the unburnt mainly ascribable to the fuel characteristics.
2015-09-06
Technical Paper
2015-24-2516
Panayotis Dimopoulos Eggenschwiler, Daniel Schreiber
Particulate matter in diesel exhaust is captured in diesel particulate filters (DPFs). Since increased load in the filter and thus increased pressure drop deteriorates the engine performance, the filter load of the DPF has to be removed during a process referred to as regeneration. Measures for successful regeneration aim at accelerating soot oxidation and increase fuel consumption. Regeneration lay-out and thus fuel consumption increase is strongly depending on the oxidation behavior of soot. The aim of the present study is the investigation of soot oxidation characteristics. Therefore particle filters have been loaded with soot using the exhaust gas of small heavy duty vehicle operated under defined conditions on an engine dynamometer. The particle filters have been then dismantled and fragmented on their constituting segments. Each filter segment has been regenerated individually in a specifically designed test bench.
2015-09-06
Technical Paper
2015-24-2521
José Ramón Serrano, Pedro Piqueras, Emanuele Angiolini, Cesare Meano, Joaquín De La Morena
Abstract The abatement of nitrogen oxides emissions is a topic of major concern for automotive manufacturers. In addition to aftertreatment solutions such as LNT or SCR devices, the use of exhaust gas recirculation (EGR) is necessary in most of the applications to meet emissions regulations. Due to the high specific humidity of the exhaust gases, a high condensate flow may be generated if EGR gases are significantly cooled down. In the case of long-route EGR (LR-EGR) usage, this condensate flow would reach the compressor wheel. This paper explores the variables governing the condensation process and the potential effects of the liquid droplets and streams on the compressor wheel durability combining experimental and theoretical approach. For this purpose, visualization of both the condensate flow and the compressor wheel are performed. Tests are conducted in a flow test rig in which LR-EGR water content is reproduced by water injection on the hot air mass flow.
2015-09-06
Technical Paper
2015-24-2531
Marco Leonetti, Michael Bargende, Martin Kreschel, Christoph Meier, Horst Schulze
Abstract Due to the demands for today's passenger cars regarding fuel consumption and emissions, exhaust turbo charging has become a fundamental step in achieving these goals. Especially in upper and middle class vehicles it is also necessary to consider the noise comfort. Today, floating bushings are mainly used as radial bearings in turbochargers. In the conventional operating range of the turbocharger dynamic instability occurs in the lubrication films of the bearings. This instability is transferred by structure-borne noise into audible airborne sound and known as constant tone phenomenon. This phenomenon is not the major contributor of the engine noise but its tonal character is very unpleasant. In order to gain a more detailed understanding about the origin of this phenomenon, displacement sensors have been applied to the compressor- and the turbine-side of the rotor, to be able to determine the displacement path.
2015-09-06
Technical Paper
2015-24-2543
Damien Maroteaux, Damien Le Guen, Eric Chauvelier
Abstract The worldwide trends for future CO2 regulation standards will push car manufacturers for more and more development of Electric and Hybrid Electric Vehicles. Many different configurations of Hybrid Electric Vehicles exist, including parallel hybrid, series hybrid, plug-in hybrids, Battery Electric Vehicles with Range Extender, etc. The choice of the optimal architecture depends on many different parameters, and is a key issue to be solved at the beginning of vehicle development. In order to help decision making in the early phase of projects, simulation tools are essential. A specific simulation platform for simulation of fuel economy and CO2 emissions for hybrid electric vehicles has been developed by Renault.
2015-09-06
Technical Paper
2015-24-2538
Lars Christian Riis Johansen, Ingemar Denbratt, Stina Hemdal
Abstract The emissions from a parallel hybrid combustion engine and electric powertrain operated on a modified New European Drive Cycle (NEDC) was investigated in order to determine the relation between emissions and the road and engine load profile. The effect of simulated electric motor assistance during accelerations on emissions was investigated as a means to reduce particulate and gaseous emissions. The time resolved particulate number and size distribution was measured in addition to gaseous emissions. The combustion engine was a downsized, three cylinder spark ignited direct injection (SIDI) turbocharged engine fuelled with gasoline. Electric motor assistance during accelerations was simulated by reduction of the vehicle mass. This reduced engine load during accelerations. Fuel rich engine transients occurred during accelerations. NOx emissions were reduced with electric assistance due to a reduction in engine load.
2015-09-06
Technical Paper
2015-24-2548
Florian Tschopp, Tobias Nüesch, Mu Wang, Christopher Onder
Abstract This paper deals with the problem of obtaining the optimal energy and emission management strategy for a diesel hybrid electric vehicle. The vehicle is assumed to be equipped with a selective catalytic reduction device for the removal of harmful NOx emissions. The authors present a model-based procedure: The energy flows of the hybrid vehicle are modelled in a standard way, while the engine-out emissions are calculated based on a temperature-corrected engine map. For the simulation of the SCR system a combination of two existing first-principle physical models is used. The optimal energy and emission strategy for a given driving cycle is then obtained using dynamic programming. In terms of results, three case studies are presented. One case study illustrates the trade-off between fuel consumption and tailpipe NOx emissions for various relative weights of these objectives.
2015-09-06
Technical Paper
2015-24-2390
Shashi Aithal, Stefan Wild
Abstract Design and optimization of automotive engines present unique challenges on account of the large design space and conflicting constraints. A notable example of such a problem is optimizing the fuel consumption and reducing emissions over the drive cycle of an automotive engine. There are over twenty design variables (including operating conditions and geometry) for the above-mentioned problem. Conducting design, analyses, and optimization studies over such a large parametric space presents a serious computational challenge. The large design parameter space precludes the use of detailed numerical or experimental investigations. Physics-based reduced-order models can be used effectively in the design and optimization of such problems.
2015-09-06
Technical Paper
2015-24-2391
Dimitris Tsokolis, Stefanos Tsiakmakis, Georgios Triantafyllopoulos, Anastasios Kontses, Zisis Toumasatos, Georgios Fontaras, Athanasios Dimaratos, Biagio Ciuffo, Jelica Pavlovic, Alessandro Marotta, Zissis Samaras
The paper describes the development of a modelling approach to simulate the effect of the new Worldwide harmonized Light duty Test Procedure (WLTP) on the certified CO2 emissions of light duty vehicles. The European fleet has been divided into a number of segments based on specific vehicle characteristics and technologies. Representative vehicles for each segment were selected. A test protocol has been developed in order to generate the necessary data for the validation of the vehicle simulation models. In order to minimize the sources of uncertainty and the effects of flexibilities, a reference “template model” was developed to be used in the study. Subsequently, vehicle models were developed using AVL Cruise simulation software based on the above mentioned template model. The various components and sub-modules of the models, as well as their input parameters, have been defined with the support of the respective OEMs.
2015-09-06
Technical Paper
2015-24-2388
Jordan Rudloff, Alessio Dulbecco, Gregory Font
IFP Energies nouvelles (IFPEN) has a large experience in the development of engine simulation platforms. During the last decade, the Dual Flame Model (DFM), a physical 0-dimensional (0D) combustion model designed for Diesel applications, was developed and continuously improved. The DFM formalism allows to represent quite precisely the in-cylinder combustion process scenario, by accounting for the first order relevant physics impacting fuel oxidation. First of all, this allows to account for the impact of engine actuators on combustion (e.g. injection systems performing complex injection strategies, Low Pressure and High Pressure EGR loops,…) and then to describe the pollutant emissions formation processes, being chemical kinetics strongly dependent on the in-cylinder thermochemical conditions. The aim of this communication is to present the potential of using the DFM model in the different stages of a Diesel engine development process for pollutant emissions optimization.
2015-09-06
Technical Paper
2015-24-2423
Roberto Saracino, Maria Rosaria Gaballo, Soenke Mannal, Stefan Motz, Antonio Carlucci, Marco Benegiamo
Abstract The strategies adopted to control the combustion in Diesel applications play a key role when dealing with current and future requirements of automotive market for Diesel powertrain systems. The traditional “open loop” control approach aims to achieve a desired combustion behaviour by indirect manipulation of the system boundary conditions (e.g. fresh air mass, fuel injection). On the contrary, the direct measurement of the combustion process, e.g. by means of in-cylinder pressure sensor, offers the possibility to achieve the same target “quasi” automatically all over the vehicle lifetime in widely different operating conditions. Beside the traditional combustion control in closed loop (i.e. based on inner torque and/or combustion timing), the exploitation of in-cylinder pressure signal offers a variety of possible further applications, e.g. smart detection of Diesel fuel quality variation, control of combustion noise, modeling engine exhaust emission (e.g. NOx).
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