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Viewing 211 to 240 of 22820
2015-04-14
Technical Paper
2015-01-1162
Frank Atzler, Michael Wegerer, Fabian Mehne, Stefan Rohrer, Christoph Rathgeber, Sebastian Fischer
Abstract Modern vehicles need to fulfil challenging requirements with respect to emissions, noise and fuel consumption. Up to the EU5 legislation a sound steady state application was sufficient for passenger car Diesel engines to meet these requirements, and fuel consumption was less in the focus than the emissions of nitrous oxides and soot, hydrocarbons and carbon monoxide. Future legislation will require not only tighter limits in emissions but additionally will set fuel consumption targets. More demanding drive cycles will make it even more difficult to achieve these targets. Additional to measures on the combustion engine, moderate electrification for energy recuperation as well as the supply of electrical generated torque to the drive train will increasingly find its way into modern passenger cars. The presence of an electric machine can be used not only to reduce the fuel consumption but also the emissions of the combustion engine.
2015-04-14
Journal Article
2015-01-1257
David B. Roth, Iago Gonzalez Tabares, Anxo Sotelo Álvarez
Abstract Cooled LPL EGR is a proven means of improving the efficiency of a Gasoline Turbocharged Direct-Injection engine. One of the most significant hurdles to overcome in implementing a LPL EGR system is dealing with condensation of water near the entrance of the turbocharger's compressor wheel. A gasoline engine, and to a greater extent a spark ignition engine running on Natural Gas, will encounter enough water condensation at some steady-state conditions to damage the compressor wheel due to the high-speed collision between the compressor blades and the water droplets. As an alternative to not utilizing beneficial EGR at the condensing conditions, the team at BorgWarner have developed a LPL EGR mixer that is effective at condensing and collecting the water droplets and routing the water around the compressor wheel. The new Condensing EGR mixer was developed from the known concept of utilizing a mild venturi section to enhance EGR delivery and mixing.
2015-04-14
Technical Paper
2015-01-1259
Tapio Pohjalainen, Martti Larmi
Abstract This study presents a novel crank mechanism which enables easy and fast compression ratio adjustment. The novel crank mechanism and piston travel are explained and highlighted. The basic idea is that eccentric gear is installed on a crankshaft web. Eccentric gear is fitted to the big end of the connection rod and eccentricity is controlled by rotating the control gear a discrete amount. Thus the position of eccentricity is varied and controls an effective stroke length. The compression ratio is adjusted to best fit current load demand, either optimizing fuel efficiency or engine power and torque. Adjustments are individual to each cylinder. The system is capable of adjusting from min to max within 10 milliseconds [ms]. Emphasis is on reduction of CO2 emissions and reducing fuel consumption, especially at part load condition. The governing mechanical equations are presented.
2015-04-14
Journal Article
2015-01-1306
Jeremy S. Neubauer, Eric Wood, Ahmad Pesaran
Abstract Battery second use-putting used plug-in electric vehicle (PEV) batteries into secondary service following their automotive tenure-has been proposed as a means to decrease the cost of PEVs while providing low cost energy storage to other fields (e.g., electric utility markets). To understand the value of used automotive batteries, however, we must first answer several key questions related to battery degradation, including: How long will PEV batteries last in automotive service? How healthy will PEV batteries be when they leave automotive service? How long will retired PEV batteries last in second-use service? How well can we best predict the second-use lifetime of a used automotive battery? Under the support of the U.S. Department of Energy's Vehicle Technologies Office, the National Renewable Energy Laboratory has developed a methodology and the requisite tools to answer these questions, including the Battery Lifetime Simulation Tool (BLAST).
2015-04-14
Journal Article
2015-01-1635
Zhen Zhang, Stephan Stadlbauer, Harald Waschl, Richard Fuerhapter, Luigi del Re
Abstract At the moment, no equipment is available for fast measurements of particulate matter (PM) from production CI engines, especially during transients. Against this background, virtual sensors may be an option, provided their precision can be validated. This paper presents a new approach to estimate PM emission based only on in-cylinder pressure data. To this end, an in-cylinder pressure trace is measured with a high resolution (0.5 CAD) and every trace is divided into 8 segments according to critical cylinder events (e.g. opening of the valves or the beginning of injection). A piecewise principle component analysis (PCA) is used to compress the information. This information is then used for PM estimation via a second order polynomial model structure. The key element is the separate use of pressure trace information before and during the early stages of combustion. The model is parameterized by steady points and transient experiments which include parts of the FTP and the NEDC.
2015-04-14
Technical Paper
2015-01-1631
Michinori Tani, Atsuhiro Miyauchi, Yoshiaki Matsuzono
Abstract Recently, automotive emission regulations are being further tightened, such as the Tier III/LEV III in the U.S. As a result, reducing cost of after-treatment systems to meet these strict regulations has become an urgent issue, and then the demand for high-precision air-fuel ratio (A/F) control which can achieve this cost reduction is high [1]. On the other hand, in order to meet rapidly changing market needs, it is becoming difficult to keep enough development periods that enable sufficient calibration by trial-and-error, such as feedback-gain calibration. This leads to an increase in three-way catalytic converter costs in some cases. For these reasons, it is necessary to construct control system that can make full use of hardware capabilities, can shorten development periods regardless of the skill level of engineers.
2015-04-14
Journal Article
2015-01-1620
Feilong Liu, Jeffrey Pfeiffer
Abstract Low-pressure, Cooled Exhaust Gas Recirculation (LPC EGR) brings significant fuel economy, NOx reduction and knock suppression benefits to a modern, boosted, downsized Spark Ignition (SI) engine. As a prerequisite to design an engine control system for LPC EGR, this paper presents development of a set of estimation algorithms to accurately estimate the flow rate, pressure states and thermal states of the LPC EGR-related components.
2015-04-14
Technical Paper
2015-01-1648
Hendrik Golzke, Heiko Holler, Wolfgang Friedrich, Philippe Leick, Ulrich Schoenauer, Andreas Dreizler
Abstract The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.
2015-04-14
Technical Paper
2015-01-1639
Indranil Brahma, Odinmma Ofili, Matthew Campbell, Henrique Chiang, Vincent Giralo, Peter Stryker, Daniel Johnson, Aaron Clark
Abstract EGR flow rate measurements on production engines are commonly made using orifices or flow nozzles. These devices increase the exhaust pressure resulting in an increase in fuel consumption. Further, they are accurate and recommended only for steady state flow, and not pulsating flow encountered in engines. In this work measurements made at the EGR cooler, such as the pressure drop across it and the inlet and outlet temperatures, have been examined for their ability to predict mass flow rate through the cooler. Direct measurements of pulsating flow through an EGR cooler were made by routing all of the engine exhaust flow through the cooler while making accurate measurements of the air and fuel flowing into the engine. Based on dimensional arguments, the flow resistance of the EGR cooler was characterized by a loss coefficient within the standard head loss energy equation.
2015-04-14
Technical Paper
2015-01-1638
Dejan Kihas, Michael R. Uchanski
Recently, numerous researchers and Original Equipment Manufacturers (OEMs) have developed diesel engine-out nitrogen oxides (NOx) estimation algorithms that are capable of running in real-time on production Electronic Control Units (ECUs). These are generally referred to as virtual sensors or inferential sensors. NOx estimators are typically installed to improve On-Board Diagnostics (OBD) monitors or to lower bill of material costs by replacing physical NOx sensors. This paper reviews the literature of on-ECU NOx models in order to document the state of the art and identify directions for future work. The discussion includes applications of NOx estimators, accuracy of NOx estimators, required sensor inputs, sources of error, calibration effort, and ECU resource consumption.
2015-04-14
Technical Paper
2015-01-1637
SeungBum Kim, SeongMin Park, DongUk Han
Abstract This paper focuses on the vehicle test result of the US fuel economy test cycles such as FTP75, HWY and US06 with model based Cooled EGR system. Cooled EGR SW function was realized by Model Based Development (internal rapid prototyping) using iRPT tool. With EGR, mixing exhaust gas with clean air reduces the oxygen concentration in the cylinder charge, as a result, the combustion process is slowed, and the combustion temperature drops. This experiment confirmed that the spark timing was more advanced without knocking and manifold pressure was increased in all cases with EGR. A positive potential of fuel economy improvement on FTP mode, US06 mode have seen in this experiment but not for HWY where the engine load is quite low and the spark advance is already optimized. As a result, fuel economy was increased by maximum 3.3% on FTP, 2.7% on US06, decreased by 0.3% on HWY mode respectively with EGR.
2015-04-14
Journal Article
2015-01-1714
Usman Asad, Jimi Tjong
Abstract This study describes a zero-dimensional algorithm for tracking the intake dilution in real-time. The inputs to the model are the oxygen concentration from the exhaust oxygen sensor, the manifold air pressure and temperature (MAP/MAT), the mass air flow (MAF) and the estimated fuel injected per cycle from the engine control module. The intake manifold, the exhaust manifold and EGR system are discretized into 3 volumes and the detailed concentrations of the gas species comprising the exhaust, EGR and intake streams are tracked at each time step (on a cycle-by-cycle basis). The model does not need the EGR ratio to be known in advance and is also applicable to oxygenated fuels such as ethanol. The model response is tuned to a multi-cylinder engine and the model output is empirically validated against a wide range of engine operations including load and EGR transients.
2015-04-14
Technical Paper
2015-01-1684
KV Shivaprasad, PR Chitragar, GN Kumar
Abstract This article experimentally characterizes the combustion and emission parameters of a single cylinder high speed SI engine operating with different concentrations of hydrogen with gasoline fuel. For this purpose, the conventional carbureted high speed SI engine was modified into an electronically controllable engine, wherein ECU was used to control the injection timings and durations of gasoline. The experiments have been conducted for different engine speeds at various throttle positions. The experimental results demonstrated that engine brake power and brake thermal efficiency increased to certain extent and then decreases with the increase of hydrogen percentage in the fuel blend. The experimental results revealed that heat release and cylinder pressure increased with addition of hydrogen fraction till 20%. It also showed the reduction in HC and CO emissions in comparison with pure gasoline.
2015-04-14
Technical Paper
2015-01-1072
Aron D. Butler, Rafal A. Sobotowski, George J. Hoffman, Paul Machiele
Abstract The EPAct/V2/E-89 gasoline fuel effects program collected emissions data for 27 test fuels using a fleet of 15 high-sales cars and light trucks from the 2008 model year (all with port fuel injection). The test fuel matrix covered values of T50, T90, vapor pressure, ethanol content, and total aromatic content spanning ranges typical of market gasolines. Emission measurements were made over the LA92 cycle at a nominal temperature of 24°C (75°F). The resulting emissions database of 956 tests includes a particulate matter (PM) mass measurement for each. Emission models for PM fuel effects were fit based on terms for which the fuel matrix was originally optimized, with results published by EPA in a 2013 analysis report. This paper presents results of a subsequent modeling analysis of this PM data using the PM Index fuel parameter, and compares these models to the original versions.
2015-04-14
Journal Article
2015-01-0838
Zhiqin Jia, Ingemar Denbratt
Abstract Studies have shown that premixed combustion concepts such as PCCI and RCCI can achieve high efficiencies while maintaining low NOx and soot emissions. The RCCI (Reactivity Controlled Compression Ignition) concept use blending port-injected high-octane fuel with early direct injected high-cetane fuel to control auto-ignition. This paper describes studies on RCCI combustion using CNG and diesel as the high-octane and high-cetane fuels, respectively. The test was conducted on a heavy-duty single cylinder engine. The influence of injection timing and duration of the diesel injections was examined at 9 bar BMEP and1200 rpm. In addition, experiments were conducted using two different compression ratios, (14 and 17) with different loads and engine speeds. Results show both low NOx and almost zero soot emissions can be achieved but at the expense of increasing of unburned hydrocarbon emissions which could potentially be removed by catalytic after-treatment.
2015-04-14
Journal Article
2015-01-0988
Fabien Ocampo, Virginie Harle, Naotaka Ohtake, Renaud Rohe, Barry W.L. Southward
Abstract The reduction of NOx to meet current diesel regulation standards has been achieved using two main technologies named NH3-SCR and LNT. In the forthcoming years, the implementation of new and colder test cycles such as “real driving emissions” (RDE), combined with CO2 targets (95 g/km is 2020 target in Europe) will require higher NOx storage capacity (NSC) in the low temperature region (120-350°C). On the other hand, lean-burn Gasoline vehicles, emitting exhaust gases at higher temperatures, will require improved NSC over a broader temperature range (200-500°C). Therefore, the development of more efficient NSC materials is an area of extensive study by original equipment manufacturers (OEMs), catalysts manufacturers, and raw materials suppliers. Today, ceria is a key component in the formulation of active NSC washcoats.
2015-04-14
Technical Paper
2015-01-1250
Nisar Al-Hasan, Johannes Beer, Jan Ehrhard, Thomas Lorenz, Ludwig Stump
Abstract In the past few years the gasoline direct injection (GDI) downsizing approach was the dominating gasoline engine technology used to reduce CO2 emission and to guarantee excellent transient performance. Forecasts for the next several years indicate that the worldwide market share of GDI engines will grow further. By 2022 it is expected that the gasoline DI engine will be the most popular combustion engine for passenger car application. However in the future the gasoline engine will have to comply with more stringent emission and CO2 standards. The European legislation demands a fleet average CO2 emission of 95g/km latest by 2021. Therefore, CO2 emission improvement, without compromising driveability, is the major goal of powertrain development. The perspective of more stringent CO2 and emission legislation in highly loaded drive cycle necessitates major development efforts.
2015-04-14
Journal Article
2015-01-1683
Bernie Porter, Hugh Blaxill, Noor Jariri
Abstract The 2025 Corporate Average Fleet Economy (CAFE) fuel economy regulations are a significant challenge to the automotive industry. These regulations require dramatic increases in vehicle fleet fuel economy. This paper will identify and analyze a portfolio of technologies that have the potential to achieve the 2025 CAFE fuel economy targets, focusing on powertrain enhancements. The study uses a MAHLE Powertrain developed fleet modeling tool and a range of vehicle technologies and powertrain data taken from MAHLE's global research and development activities. Powertrain technologies considered include extreme engine downsizing, dilute combustion, friction reduction, hybridization, diesel and alternative fuels. The vehicle technologies analyzed include vehicle light weighting, reduced rolling resistance, advanced transmissions and improved aerodynamics.
2015-04-14
Collection
This technical paper collection focuses on particle emissions from combustion engines, including measurement and testing methods, and the effects of changes in fuel composition. Papers also cover the topics of the environmental and health effects of elemental carbon and organic carbon that constitutes solid cored particles plus the environmental and health effects of secondary organic aerosol emissions. This includes particulate emissions from both gasoline and diesel engines.
2015-04-14
Journal Article
2015-01-0993
Timothy V. Johnson
Abstract This review paper summarizes major developments in vehicular emissions regulations and technologies from 2014. The paper starts with the key regulatory advancements in the field, including newly proposed Non-Road Mobile Machinery regulations for 2019-20 in Europe, and the continuing developments towards real driving emissions (RDE) standards. An expert panel in India proposed a roadmap through 2025 for clean fuels and tailpipe regulations. LD (light duty) and HD (heavy-duty) engine technology continues showing marked improvements in engine efficiency. Key developments are summarized for gasoline and diesel engines to meet both the emerging NOx and GHG regulations. HD engines are demonstrating more than 50% brake thermal efficiency using methods that can reasonably be commercialized. Next, NOx control technologies are summarized, including SCR (selective catalytic reduction), lean NOx traps, and combination systems. Emphasis is on durability and control.
2015-04-14
Journal Article
2015-01-1034
Homayoun Ahari, Michael Smith, Michael Zammit, Kenneth Price, Jason Jacques, Thomas Pauly, Lin Wang
Significant reduction in Nitrogen Oxide (NOx) emissions will be required to meet LEV III/Tier III Emissions Standards for Light Duty Diesel (LDD) passenger vehicles. As such, Original Equipment Manufacturers (OEMs) are exploring all possible aftertreatment options to find the best balance between performance, durability and cost. The primary technology adopted by OEMs in North America to achieve low NOx levels is Selective Catalytic Reduction (SCR). The critical parameters needed for SCR to work properly are: an appropriate reductant such as ammonia (NH3) provided as Diesel Exhaust Fluid (DEF), which is an aqueous urea solution 32.5% concentration in weight with water (CO(NH2)2 + H2O), optimum operating temperatures, and optimum nitrogen dioxide (NO2) to NOx ratios (NO2/NOx). The NO2/NOx ratio is most influenced by Precious Group Metals (PGM) containing catalysts upstream of the SCR catalyst.
2015-04-14
Technical Paper
2015-01-0863
Hideyuki Ogawa, Peilong Zhao, Taiki Kato, Gen Shibata
Abstract Dual fuel combustion with premixed natural gas as the main fuel and diesel fuel as the ignition source was investigated in a 0.83 L, single cylinder, DI diesel engine. At low loads, increasing the equivalence ratio of natural gas to around 0.5 with intake throttling makes it possible to reduce the THC and CO emissions as well as to improve the thermal efficiency. At high loads, increasing the boost pressure moderates the combustion, but increases the THC and CO emissions, resulting in deterioration of the thermal efficiency. The EGR is essential to suppress the rapid combustion. As misfiring occurs with a compression ratio of 14.5 and there is excessively rapid combustion with 18.5 compression ratio, 16.5 is a suitable compression ratio.
2015-04-14
Journal Article
2015-01-1085
Marc C. Besch, Joshua Israel, Arvind Thiruvengadam, Hemanth Kappanna, Daniel Carder
Abstract This study was aimed at experimentally investigating the impact of diesel/natural gas (NG) dual-fuel retrofitting onto gaseous emissions emitted by i) legacy, model year (MY) 2005 heavy-duty engines with cooled EGR and no after-treatment system, and ii) a latest technology engine equipped with DPF and urea-SCR after-treatment systems that is compliant with 2010 US-EPA emissions standards. In particular, two different dual-fuel conversion kits were evaluated in this study with pure methane (CH4) being used as surrogate for natural gas. Experiments were conducted on an engine dynamometer over a 13-mode steady-state test cycle as well as the transient FTP required for engine certification while gaseous emissions were sampled through a CVS system. Tailpipe NOx emissions were observed at a comparable level for diesel and diesel/CH4 dual-fuel operation for the 2010 compliant engine downstream the SCR.
2015-04-09
WIP Standard
J3094
Create a standard for measurement of the performance characteristics of an Internal Heat Exchanger. The standard should make it easier to innovate designs and bring improvements to this new technology.
2015-04-08
Magazine
Hydraulics still in control of off-highway needs Engineers continue to master electronic controllers and software to help systems manage engine speeds and boost efficiency, to the ultimate benefit of both OEMs and end-users. Off-highway calibration challenges-big and complex As the final set of Tier 4 regulations kick in for engines greater than 750 hp (560 kW), calibration efforts must contend with complex engine and aftertreatment systems. Engine manufacturers and service providers deal with this complexity, but does it need to be so? DEF delivery modelling for SCR systems Researchers characterize a 0-D model of a urea delivery module, oriented to model-based control and to the simulation of the system response to fault injections finalized to diagnosis validation.
2015-03-30
Technical Paper
2015-01-0126
Meng Choung Chiong, Srithar Rajoo, Alessandro Romagnoli
Abstract This paper presents a concept for new piston expander utilizing nozzle as part of a secondary steam cycle to recover exhaust energy. A commercial 1D simulation tool, AVL BOOST, was used to model the system, and comparison study was carried out between the conventional and nozzle piston expanders. It was found the nozzle piston expander could increase output power from a minimum of 0.73kW up to a maximum of 4.75kW. The simulation study has shown that the concept of using nozzle to admit steam into the piston expander has potential to improve engine system level efficiency.
2015-03-30
Technical Paper
2015-01-0111
Sarapon Thitipatanapong, Sathaporn Chuepeng, Poranat Visuwan
Abstract Encouraging the use of alternative fuels available in Thailand is mainly due to fuel crisis within the past few decades. The government has recently drafted a renewable energy long-term plan to increase biofuel production. This has emboldened biodiesel to be used as fuel for agriculture and transportation, in particular. Diesel engines are promising for reducing carbon dioxide emissions related fuel energy consumption. Ordinarily, diesel combustion generates particulate matter and nitrogen oxides in trade-off relationship. However, advanced techniques for engine technology and aftertreatment devices have been abundantly developed to mitigate these hindrances. To break the trade-off emissions, an example technique is to fuel engines with biodiesel incorporated with exhaust gas recirculation. Among available options, nonthermal plasma (NTP) is one of the techniques that charges exhaust gas with high power electricity to reduce some emissions.
2015-03-27
Article
Sales of diesel-powered light vehicles are up 70% and the latest engines are cleaner than ever. But the diesel industry still faces significant headwinds to greater penetration.
2015-03-25
Article
A team of researchers from the Cockrell School of Engineering at The University of Texas at Austin have developed a mutant yeast strain that could lead to a more efficient and economical biofuel production process, and from non-food sources.
2015-03-13
Article
Andy Pontius, Chief Technologist for Faurecia Emissions Control Technologies in North America, talks about even lighter-weight exhaust systems and meeting future powertrain-systems expectations.
Viewing 211 to 240 of 22820

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