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Viewing 241 to 270 of 22467
2014-04-01
Technical Paper
2014-01-1161
Donald Selmanaj, Harald Waschl, Michael Schinnerl, Sergio Savaresi, Luigi del Re
Abstract Especially in view of more and more stringent emission legislation in passenger cars it is required to reduce the amount of pollutants. In the case of Diesel engines mainly NOx and PM are emitted during engine operation. The main influence factors for these pollutants are the in-cylinder oxygen concentration and the injected fuel amount. Typically the engine control task can be divided into two separate main parts, the fuel and the air system. Commonly air system control, consisting of a turbocharger and exhaust gas recirculation control, is used to provide the required amount of oxygen and address the emission targets, whereas the fuel is used to provide the desired torque. Especially in transient maneuvers the different time scales of both systems can lead to emission peaks which are not desired. Against this background in this work instead of the common way to address the air system, the fuel system is considered to reduce emission peaks during transients. The idea is to start from a base calibration and adapt the injection parameters, like start and amount of pilot and main injection, to reduce transient emission peaks.
2014-04-01
Technical Paper
2014-01-1082
Ayman Moawad, Aymeric Rousseau
Abstract Manufacturers have been considering various technology options to improve vehicle fuel economy. One of the most cost effective technology is related to advanced transmissions. To evaluate the benefits of transmission technologies and control to support the 2017-2025 CAFE regulations, a study was conducted to simulate many of the many types of transmissions: Automatic transmissions, Manual Transmission as well as Dual Clutch Transmissions including the most commonly used number of gears in each of the technologies (5-speeds, 6-speeds, and 8-speeds). Different vehicle classes were also analyzed in the study process: Compact, Midsize, Small SUV, Midsize SUV and Pickup. This paper will show the fuel displacement benefit of each advanced transmission across vehicle classes.
2014-04-01
Technical Paper
2014-01-1169
Jean-Claude Habumuremyi
Since 2004, INERGY is working on the development of SCR (Selective Catalytic Reduction) system Components and controls to enable the reduction of NOx (Nitrogen Oxides) in the exhaust gas using an aqueous urea solution. This paper is focused on the pump control strategy. In this paper, we modelled an INERGY SCR pump system (gear pump, DC motor, line and injector) used. Then we considered PID (Proportional-Integral-Derivative) controllers since they are common in the automotive industry. We developed 4 controllers to achieve the necessary system function which include: line filling, pressure build-up, pressure hold-up, and purge. Windup introduced by saturation of the motor command and transition between the controllers were taken into account during development. We tested different anti-windup approaches on this model. We derived lessons regarding the overshoot, the rise time and the performance of the different anti-windup techniques. Then we showed the results of anti-windup methods applied on INERGY 1st and 2nd generation SCR systems
2014-04-01
Technical Paper
2014-01-1135
Chitralkumar V. Naik, Long Liang, Karthik Puduppakkam, Ellen Meeks
Abstract 3-D Computational Fluid Dynamics (CFD) simulations have been performed using a detailed reaction mechanism to capture the combustion and emissions behavior of an IFP Energies nouvelles optical gasoline direct injection engine. Simulation results for in-cylinder soot volume fraction have been compared to experimental data provided by Pires da Cruz et al. [1] The engine was operated at low-load and tests were performed with parametric variations of the operating conditions including fuel injection timing, inlet temperature, and addition of fuel in the intake port. Full cycle simulations were performed including intake and exhaust ports, valve and piston motion. A Cartesian mesh was generated using automatic mesh generation in the FORTÉ CFD software. For the simulations, a 7-component surrogate blend was used to represent the chemical and physical properties of the European gasoline used in the engine tests. A validated detailed combustion mechanism containing 230 species and 1740 reactions was employed to model the chemistry of the fuel surrogate combustion and emissions.
2014-04-01
Technical Paper
2014-01-1124
Raouf Mobasheri, Seyed Alireza Khabbaz
Abstract Exhaust Gas Recirculation (EGR) is an effective pre-treatment technique, which has been widely used to decrease the amount of the oxides of nitrogen (NOx) emission from diesel engines. However, the use of high EGR rates leads to the reduction in oxygen availability in the burning regions of the combustion chamber which impairs the soot oxidation process. Consequently, higher soot generated by EGR leads to long-term usage problems inside the engines such as higher carbon deposits, lubricating oil degradation and enhanced engine wear. In this study, CFD modeling has been carried out to analyze the effects of high EGR rates in conjunction with optimum multiple injection strategies. A heavy-duty DI Diesel engine has been modeled to study the engine performance and emissions with various EGR rates (from 0% to 40%). The selected operating points have been achieved with the same injection profile including a main and post injection for all considered cases. The results showed the effectiveness of multiple injections at controlling soot emission under high EGR conditions.
2014-04-01
Technical Paper
2014-01-0673
Charles Sprouse III, Christopher Depcik
Abstract Significant progress towards reducing diesel engine fuel consumption and emissions is possible through the simultaneous Waste Heat Recovery (WHR) and Particulate Matter (PM) filtration in a novel device described here as a Diesel Particulate Filter Heat Exchanger (DPFHX). This original device concept is based on the shell-and-tube heat exchanger geometry, where enlarged tubes contain DPF cores, allowing waste heat recovery from engine exhaust and allowing further energy capture from the exothermic PM regeneration event. The heat transferred to the working fluid on the shell side of the DPFHX becomes available for use in a secondary power cycle, which is an increasingly attractive method of boosting powertrain efficiency due to fuel savings of around 10 to 15%. Moreover, these fuel savings are proportional to the associated emissions reduction after a short warm-up period, with startup emissions relatively unchanged when implementing a WHR system. Due to the absence of prior DPFHX research and the unique heat transfer process present, this effort describes construction of a prototype DPFHX and subsequent WHR experiments in a single cylinder diesel engine test cell with a comparison between heat exchanger performance with and without DPF cores installed.
2014-04-01
Technical Paper
2014-01-0640
C. Scott Sluder, John M.E. Storey, Michael J. Lance
Abstract Fouling in EGR coolers occurs because of the presence of soot and condensable species (such as hydrocarbons) in the gas stream. Fouling leads to one of two possible outcomes: stabilization of effectiveness and plugging of the gas passages within the cooler. Deposit formation in the cooler under high-temperature conditions results in a fractal deposit that has a characteristic thermal conductivity of ∼0.033 W/m*K and a density of 0.0224 g/cm3. Effectiveness becomes much less sensitive to changes in thermal resistance as fouling proceeds, creating the appearance of “stabilization” even in the presence of ongoing, albeit slow, deposit growth. Plugging occurs when the deposit thermal resistance is several times lower because of the presence of large amounts of condensed species. The deposition mechanism in this case appears to be soot deposition into a liquid film, which results in increased packing efficiency and decreased void space in the deposit relative to high-temperature deposits.
2014-04-01
Technical Paper
2014-01-0629
Michael J. Lance, John Storey, Sam Lewis, C. Scott Sluder
Abstract All high-pressure exhaust gas recirculation (EGR) coolers become fouled during operation due to thermophoresis of particulate matter and condensation of hydrocarbons present in diesel exhaust. In some EGR coolers, fouling is so severe that deposits form plugs strong enough to occlude the gas passages thereby causing a complete failure of the EGR system. In order to better understand plugging and means of reducing its undesirable performance degradation, EGR coolers exhibiting plugging were requested from and provided by industry EGR engineers. Two of these coolers contained glassy, brittle, lacquer-like deposits which were analyzed using gas chromatography-mass spectrometry (GC-MS) which identified large amounts of oxygenated polycyclic aromatic hydrocarbons (PAHs). Another cooler exhibited similar species to the lacquer but at a lower concentration with more soot. The authors propose that lacquer deposits form when oxygenated PAHs present in the exhaust condense on the cooler walls subsequently experience nitric acid catalyzed polymerization in the presence of aldehydes.
2014-04-01
Technical Paper
2014-01-0628
Michael J. Lance, Hassina Bilheux, Jean-Christophe Bilheux, Sophie Voisin, C. Scott Sluder, Joseph Stevenson
Abstract Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with NOx emissions standards. Exhaust gas laden with particulate matter flows through the EGR cooler which causes deposits to form through thermophoresis and condensation. The low thermal conductivity of the resulting deposit reduces the effectiveness of the EGR system. In order to better understand this phenomenon, industry-provided coolers were characterized using neutron tomography. Neutrons are strongly attenuated by hydrogen but only weakly by metals which allows for non-destructive imaging of the deposit through the metal heat exchanger. Multiple 2-D projections of cooler sections were acquired by rotating the sample around the axis of symmetry with the spatial resolution of each image equal to ∼70 μm. A 3-D tomographic set was then reconstructed, from which slices through the cooler sections were extracted across different planes. High concentrations of hydrocarbon is necessary for imaging deposits and only those coolers which exhibited large organic fractions or hydrated sulfate phases were successfully characterized.
2014-04-01
Technical Paper
2014-01-0602
Lennert Sterken, Lennart Lofdahl, Simone Sebben, Tim Walker
Abstract Under a global impulse for less man-made emissions, the automotive manufacturers search for innovative methods to reduce the fuel consumption and hence the CO2-emissions. Aerodynamics has great potential to aid the emission reduction since aerodynamic drag is an important parameter in the overall driving resistance force. As vehicles are considered bluff bodies, the main drag source is pressure drag, caused by the difference between front and rear pressure. Therefore increasing the base pressure is a key parameter to reduce the aerodynamic drag. From previous research on small-scale and full-scale vehicles, rear-end extensions are known to have a positive effect on the base pressure, enhancing pressure recovery and reducing the wake area. This paper investigates the effect of several parameters of these extensions on the forces, on the surface pressures of an SUV in the Volvo Cars Aerodynamic Wind Tunnel and compares them with numerical results. To decrease the dependency of other effects within the engine bay and underbody, the SUV has been investigated in a closed-cooling configuration with upper and lower grille closed and with a smoothened underbody.
2014-04-01
Technical Paper
2014-01-0586
Essam F. Abo-Serie, Mohamed Sherif, Dario Pompei, Adrian Gaylard
Abstract A potentially important, but inadequately studied, source of passengers' exposure to pollutants when a road vehicle is stationary, with an idling engine, results from the ingestion of a vehicle's own exhaust into the passenger compartment through the HVAC intake. We developed and applied a method to determine the fraction of a vehicle's exhaust entering the cabin by this route. Further the influence of three parameters: ambient tail-wind speed, vehicle ground clearance and tail pipe angle, is assessed. The study applies Computational Fluid Dynamic (CFD) simulation to the distribution of exhaust gasses around a vehicle motorized with a 2.2 liter Diesel engine. The simulation employs efficient meshing techniques and realistic loading conditions to develop a general knowledge of the distribution of the gasses in order to inform engineering design. The results show that increasing tail-wind velocity, tail-pipe angle and ground clearance reduces the presence of CO and NO at the HVAC intake.
2014-04-01
Technical Paper
2014-01-0578
Karthikeyan N, Anish Gokhale, Narendra Bansode
Abstract The Continuous Variable Transmission (CVT) in scooters is used to transmit the power from the engine to the wheels. The CVT transmission consists of a drive pulley and a driven pulley connected to each other through a belt. The centrifugal clutch is attached to the rear pulley which transmits the power to the wheel. The engagement and disengagement of the clutch generates heat and friction heat is generated between the belt and pulley, thereby requiring continuous external cooling for its safe operation. A centrifugal fan is employed for cooling of the CVT belt. Since the cooling fan takes air from atmosphere, there is always a possibility of dust from the atmosphere entering the system, which might cause wear of pulley and belt, thereby decreasing the performance of the transmission system. The objective of the work is to analyze the dust ingress pattern in to CVT housing. The work aims at simulating the possible conditions for dust entry into the CVT housing for a complete scooter and the study of different design proposals to minimize the dust entry without compromising the cooling requirement of CVT.
2014-04-01
Technical Paper
2014-01-1128
May Yen, John Abraham
Abstract In this work, computations of reacting diesel jets, including soot and NO, are carried out for a wide range of conditions by employing a RANS model in which an unsteady flamelet progress variable (UFPV) sub-model is employed to represent turbulence/chemistry interactions. Soot kinetics is represented using a chemical mechanism that models the growth of soot precursors starting from a single aromatic ring by hydrogen abstraction and carbon (acetylene) addition and NO is modeled using the kinetics from a sub-mechanism of GRI-Mech 3.0. Tracer particles are used to track the residence time of the injected mass in the jet. For the soot and NO computations, this residence time is used to track the progression of the soot and NO reactions in time. The conditions selected reflect changes in injection pressure, chamber temperature, oxygen concentration, and density, and orifice diameter. As reported in prior work, the UFPV model predicts the ignition delay and flame lift-off height within about 25% of reported measurements.
2014-04-01
Technical Paper
2014-01-1244
Yiqun Huang, John Colvin, Asanga Wijesinghe, Meng Wang, Deyang Hou, Zuhua Fang
Abstract Dual loop EGR systems (having both a high pressure loop EGR and a low pressure loop EGR) have been successfully applied to multiple light-duty diesel engines to meet Tier 2 Bin 5 and Euro 5/6 emissions regulations [1, 2], including the 2009 model year VW Jetta 2.0TDI. Hyundai and Toyota also published their studies with dual loop EGR systems [3, 4]. More interest exists on the low pressure loop EGR effects on medium to heavy duty applications [5]. Since the duty cycles of light duty diesel and heavy duty diesel applications are very different, how to apply the dual loop EGR systems to heavy duty applications and understanding their limitations are less documented and published. As a specific type of heavy duty application, this paper studied the dual loop EGR effects on the retrofit applications of heavy duty diesel for delivery and drayage applications. The reduction of NOx emissions and the impact on fuel economy and controls are discussed. The dual loop EGR systems were fully developed and demonstrated over the full engine speed and load range including transient conditions with a nearly 50% NOx reduction over light to medium loads for drayage truck applications relative to the 2004 emissions level.
2014-04-01
Technical Paper
2014-01-1245
Venkatesh Gopalakrishnan, Alberto Vassallo, Richard C. Peterson, Joaquin De la Morena
Abstract Future diesel combustion systems may operate with significantly higher levels of boost and EGR than used with present systems. The potential benefits of higher boost and EGR were studied experimentally in a single-cylinder diesel engine with capability to adjust these parameters independently. The objective was to study the intake and exhaust conditions with a more optimum combustion phasing to minimize fuel consumption while maintaining proper constraints on emissions and combustion noise. The engine was tested at four part-load operating points using a Design of Experiments (DOE) approach. Two of the operating points correspond to low-speed and low-load conditions relevant for the New European Driving Cycle (NEDC). The other two points focus on medium load conditions representative of the World-wide harmonized Light-duty Test Procedures (WLTP). For the NEDC relevant conditions, improved fuel consumption was not achievable due to combustion noise constraints and the requirement for a very high turbocharger efficiency improvement of more than 20%.
2014-04-01
Technical Paper
2014-01-1243
Johan Genberg, Petter Tornehed, Oivind Andersson, Kristina Stenstrom
Abstract PM in diesel exhaust has been given much attention due to its adverse effect on both climate and health. As the PM emission levels are tightened, the portion of particles originating from the lubrication oil is likely to increase. In this study, exhausts from a biodiesel-fueled Euro 5 engine were examined to determine how much of the carbonaceous particles that originated from the fuel and the lubrication oil, respectively. A combination of three methods was used to determine the PM origin: chain length analysis of the hydrocarbons, determination of organic and elemental carbon (OC and EC), and the concentration of 14C found in the exhausts. It was found that the standard method for measuring hydrocarbons in PM on a filter (chain length analysis) only accounted for 63 % of the OC, meaning that it did not account for all non-soot carbon in the exhausts. Comparing the chain length method to the 14C-based method showed that the non-extractable organic carbon originated both from the oil and fuel.
2014-04-01
Technical Paper
2014-01-1240
Dongxian Song, Ning Jia, Xiangyang Guo, Xingxing Ma, Zhigang Ma, Dingwei Gao, Kejun Li, Haipeng Lai, Chunhui Zhang
Abstract Downsizing is regarded as a promising strategy to reduce the fuel consumption of gasoline engines. But downsized turbocharged engines need to take knocking into account to avoid engine damage. Low Pressure (LP) cooled exhaust gas recirculation (EGR) is an effective suppressant of knocking at boosted high load and EGR could reduce pumping loss at low loads. Both of them are helpful to improve fuel economy. In the research, a LP cooled EGR system is added to a 1.5L turbocharged PFI production gasoline engine and the compression ratio is changed from 9.3 to 11.5. The results show that the fuel reduction is 4.5% at 2000rpm 5bar (20% EGR ratio) and 9.7 % at 3000rpm 10bar (20% EGR ratio) compared with no EGR case. But at boosted high loads the fuel consumption is almost same to the production engine due to high compression ratio which results in severe knocking. In order to further reduce fuel consumption, the engine is operated in lean burn conditions. As we know, the lean operation could decrease NOX conversion efficiency of three-way catalytic (TWC), but the EGR could substantially reduce the emission of NOX.
2014-04-01
Technical Paper
2014-01-1235
Zhimin Liu, David Cleary
Abstract A 2.0L twin-scroll turbocharged SIDI engine was used to evaluate low-pressure loop water-cooled external EGR at operating conditions between 1000 rpm 75 Nm and 3000 rpm 250 Nm. The engine compression ratio was increased from 9.3 to 10.9. The maximum fuel consumption reduction potential, the boost pressure requirements, and the optimized external EGR calibration were determined. Combination of higher compression ratio and external EGR achieved 5-7% better fuel economy over mid-load region when using the twin-scroll turbocharger. A similar (4-6%) better fuel economy was observed over much of the higher-load region, including peak torque condition at 1000rpm, when the required boost pressure was provided by an externally-driven auxiliary boost system (not connected to the engine). The power consumption of auxiliary boost system (supercharger loss) was estimated and considered in fuel economy assessment. The fuel consumption reduction mechanisms of EGR were also analyzed. This study shows that reduced pumping loss attributed to about 0.5% fuel consumption reduction per 10% EGR, heat loss reduction and better mixture properties offered above 2% fuel consumption reduction per 10% EGR.
2014-04-01
Technical Paper
2014-01-1230
Thomas Wallner, Andrew Ickes, Jeff Wasil, James Sevik, Scott Miers
Abstract This study evaluates iso-butanol as a pathway to introduce higher levels of alternative fuels for recreational marine engine applications compared to ethanol. Butanol, a 4-carbon alcohol, has an energy density closer to gasoline than ethanol. Isobutanol at 16 vol% blend level in gasoline (iB16) exhibits energy content as well as oxygen content identical to E10. Tests with these two blends, as well as indolene as a reference fuel, were conducted on a Mercury 90 HP, 4-stroke outboard engine featuring computer controlled sequential multi-port Electronic Fuel Injection (EFI). The test matrix included full load curves as well as the 5-mode steady-state marine engine test cycle. Analysis of the full load tests suggests that equal full load performance is achieved across the engine speed band regardless of fuel at a 15-20°C increase in exhaust gas temperatures for the alcohol blends compared to indolene. This increase as well as the observed 2.5-3% point improvement in brake thermal efficiency of both alcohol blends compared to the reference fuel are caused by changes in air/fuel ratio; an effect ultimately attributable to the open loop engine control strategy.
2014-04-01
Technical Paper
2014-01-1199
Daisuke Takaki, Hirofumi Tsuchida, Tetsuya Kobara, Mitsuhiro Akagi, Takeshi Tsuyuki, Morihiro Nagamine
Abstract This paper presents a study of a cooled exhaust gas recirculation (EGR) system applied to a turbocharged gasoline engine for improving fuel economy. The use of a higher compression ratio and further engine downsizing have been examined in recent years as ways of improving the fuel efficiency of turbocharged gasoline engines. It is particularly important to improve fuel economy under high load conditions, especially in the turbocharged region. The key points for improving fuel economy in this region are to suppress knocking, reduce the exhaust temperature and increase the specific heat ratio. There are several varieties of cooled EGR systems such as low-pressure loop EGR (LP-EGR), high-pressure loop EGR (HP-EGR) and other systems. The LP-EGR system was chosen for the following reasons. It is possible to supply sufficient EGR under a comparatively highly turbocharged condition at low engine speed. It is important for knocking suppression to remove nitrogen oxides (NOx) from the EGR gas, which means using EGR gas from the catalyst downstream.
2014-04-01
Technical Paper
2014-01-1197
Yunlong Li, Yiqiang Pei, Jing Qin, Shaozhe Zhang, Yu Shang, Le Yang, Xuesong Wu
Abstract The effects of exhaust gas recirculation (EGR), late intake valve closure (LIVC) and high compression ratio (HCR) on the performance of a 1.6L multi-point injection (MPI) gasoline engine at 2000rpmwere investigated in this paper. Compared to the baseline engine, The improvement of fuel consumption is about 1.4%∼4.5% by using EGR only because of a reduction of pumping loss(PMEP). Nevertheless deterioration of combustion is introduced at the same time for high specific heat of EGR. The maximum EGR rate introduced in this system is limited by cyclic variations of indicate mean effective pressure (COVIMEP) at low load and fresh charge to achieve enough output power at high load. After combined LIVC and HCR, the improvement of fuel consumption is about 3.5%∼9.6% compared with the baseline engine at the same operation conditions because of significant PMEP reduction, increasing of effective compression ratio (ECR). LIVC&HCR&EGR can improve BSFC further, however, for getting stable combustion process and sufficient power, the combined technology is mainly suitable for medium load.
2014-04-01
Technical Paper
2014-01-1251
Wei Jing, William Roberts, Tiegang Fang
Abstract The measurement of the two-color line of sight soot and KL factor for NO.2 diesel and jet-A fuels was conducted in an optical constant volume combustion chamber by using a high speed camera under 1000 K ambient temperature and varied oxygen concentration conditions. The ambient conditions were set as follows: four oxygen cases including 10%, 15%, 18% and 21% at 1000 K ambient temperature. KL factor and soot temperature were determined based on the two-color pyrometry technique using two band-pass filters with wavelengths of 650 nm and 550 nm. The results show that low soot temperature is observed in the upstream inner flame along the centerline, which is surrounded by high soot temperature regions, and a high KL factor is found in the same region with a low soot temperature. The results under different times suggest that soot temperature is higher for high O2 conditions during the entire flame development; meanwhile, both integrated KL factor and soot area decrease with the increase of O2 concentration.
2014-04-01
Technical Paper
2014-01-1252
Scott Skeen, Julien Manin, Lyle Pickett, Kristine Dalen, Anders Ivarsson
Abstract Quantitative measurements of the total radiative heat transfer from high-pressure diesel spray flames under a range of conditions will enable engine modelers to more accurately understand and predict the effects of advanced combustion strategies on thermal loads and efficiencies. Moreover, the coupling of radiation heat transfer to soot formation processes and its impact on the temperature field and gaseous combustion pollutants is also of great interest. For example, it has been shown that reduced soot formation in diesel engines can result in higher flame temperatures (due to less radiative cooling) leading to greater NOx emissions. Whereas much of the previous work in research engines has evaluated radiation based on two- or three-color detection with limited spatial resolution, this work uses an imaging spectrometer in conjunction with a constant volume pre-burn vessel to quantify soot temperatures, optical thickness, and total radiation with spatial and spectral (360-700 nm) resolution along the flame axis.
2014-04-01
Technical Paper
2014-01-1254
Kar Mun Pang, Mehdi Jangi, Xue-Song Bai, Jesper Schramm
Abstract In this reported work, 2-dimsensional computational fluid dynamics studies of n-heptane combustion and soot formation processes in the Sandia constant-volume vessel are carried out. The key interest here is to elucidate how the chemical kinetics affects the combustion and soot formation events. Numerical computation is performed using OpenFOAM and chemistry coordinate mapping (CCM) approach is used to expedite the calculation. Three n-heptane kinetic mechanisms with different chemistry sizes and comprehensiveness in oxidation pathways and soot precursor formation are adopted. The three examined chemical models use acetylene (C2H2), benzene ring (A1) and pyrene (A4) as soot precursor. They are henceforth addressed as nhepC2H2, nhepA1 and nhepA4, respectively for brevity. Here, a multistep soot model is coupled with the spray combustion solver to simulate the soot formation/oxidation processes. Comparison of the results shows that the simulated ignition delay times and liftoff lengths have good agreements with the experimental measurements across wide range of operating conditions when the nhepC2H2 model is implemented.
2014-04-01
Technical Paper
2014-01-1467
Xin Wang, Yunshan Ge
Abstract Compressed natural gas (CNG) is widely used as an alternative option in spark ignition engines because of its better fuel economy and in part cleaner emissions. To cope with the haze weather in Beijing, about 2000 gasoline/CNG dual-fuel taxis are servicing on-road. According to the government's plan, the volume of alternative fuel and pure electric vehicle will be further increased in the future. Thus, it is necessary to conduct an evaluation on the effectiveness of alternative fuel on curbing vehicular emissions. This research examined the regulated emissions and particulate matter of gasoline/CNG dual-fuel taxi over New European Driving Cycle (NEDC). Emission tests in gasoline- and CNG-fuelled, cold- and warm-start modes were done for all five taxies. Test vehicles, Hyundai Elantra, are powered by 1.6L spark-ignited engines incorporated with 5-gear manual gearboxes. The taxis were registered in May and June, 2013, and their millage was within 3500 and 10000 km on odometer when the emission tests were performed.
2014-04-01
Technical Paper
2014-01-1466
Navin Kumar, Abyarth Behera, Dulari Hansdah, Murugan Sivalingam
Abstract Madhuca indica flower is a forest residue used for preparation of food and liquor in tribal areas of India. In this present investigation, bioethanol produced from madhuca indica flower by the fermentation process is proposed as an alternative fuel for diesel engines. As the cetane number of bioethanol is low, an ignition improver is required for better operation. In this study, Diethyl ether (DEE), an ignition improver is fumigated at two different flow rates viz 120 g/h and 240 g/h in the intake manifold along with the air in a single cylinder, four stroke, DI diesel engine developing a power of 4.4 kW at a rated speed of 1500 rpm. The brake thermal efficiency (BTE) is found to be higher by about 10.47 and 2.46% with 120 g/h and 240 g/h flow rate of the DEE respectively, compared to that of diesel at full load. The brake specific nitric oxide (BSNO) emission is found to be lower for both the flow rates, but the brake specific carbon monoxide (BSCO) and brake specific hydrocarbon (BSHC) emission are found to be higher for the flow rate of 240 g/h compared to 120 g/h of DEE and diesel at full load.
2014-04-01
Technical Paper
2014-01-1455
Robert L. Russell, Kent Johnson, Thomas Durbin, Nicole Davis, James Lents
Abstract Engine manufacturers have explored many routes to reducing the emissions of harmful pollutants and conserving energy resources, including development of after treatment systems to reduce the concentration of pollutants in the engine exhaust, using alternative fuels, and using alternative fuels with after treatment systems. Liquefied petroleum gas (LPG) is one alternative fuel in use and this paper will discuss emission measurements for several LPG vehicles. Regulated emissions were measured for five school buses, one box truck, and two small buses over a cold start Urban Dynamometer Driving Schedule (CS_UDDS), the Urban Dynamometer Driving Schedule (UDDS), and the Central Business District (CBD) cycle. In general, there were no significant differences in the gas phase emissions between the UDDS and the CBD test cycles. For the CS-UDDS cycle the total hydrocarbons and non-methane hydrocarbon emissions are higher than they are from the UDDS cycle. Methane and carbon monoxide emissions are also higher, but the difference isn't as pronounced.
2014-04-01
Technical Paper
2014-01-1459
Karthik Nithyanandan, Han Wu, Ming Huo, Chia-Fon Lee
Abstract Alcohols, because of their potential to be produced from renewable sources and their characteristics suitable for clean combustion, are considered potential fuels which can be blended with fossil-based gasoline for use in internal combustion engines. As such, n-butanol has received a lot of attention in this regard and has shown to be a possible alternative to pure gasoline. The main issue preventing butanol's use in modern engines is its relatively high cost of production. Acetone-Butanol-Ethanol (ABE) fermentation is one of the major methods to produce bio-butanol. The goal of this study is to investigate the combustion characteristics of the intermediate product in butanol production, namely ABE, and hence evaluate its potential as an alternative fuel. Acetone, n-butanol and ethanol were blended in a 3:6:1 volume ratio and then splash blended with pure ethanol-free gasoline with volumetric ratios of 0%, 20%, 40% to create various fuel blends. These blends were tested in a port-fuel injected spark-ignited (SI) engine and their performance was evaluated through measurements of in-cylinder pressure, and various exhaust emissions.
2014-04-01
Technical Paper
2014-01-1441
Joseph Kazour, Bizhan Befrui, Harry Husted, Michael Raney, Daniel Varble
Abstract Innovative nozzle hole shapes for inwardly opening multi-hole gasoline direct injectors offer opportunities for improved mixture formation and particulate emissions reduction. Compared to increased fuel pressure, an alternative associated with higher system costs and increased pumping work, nozzle hole shaping simply requires changes to the injector nozzle shape and may have the potential to meet Euro 6 particulate regulations at today's 200 bar operating pressure. Using advanced laser drilling technology, injectors with non-round nozzle holes were built and tested on a single-cylinder engine with a centrally-mounted injector location. Particulate emissions were measured and coking deposits were imaged over time at several operating fuel pressures. This paper presents spray analysis and engine test results showing the potential benefits of alternative non-round nozzle holes in reducing particulate emissions and enhancing robustness to coking with various operating fuel pressures.
2014-04-01
Technical Paper
2014-01-1496
Tao Tang, Dongxiao Cao, Jun Zhang, Yan-guang Zhao, Shi-jin Shuai
Abstract The diesel particulate filter (DPF) is an effective technology for particulate matter (PM) and particle number (PN) reduction. On heavy-duty diesel engines, the passive regeneration by Diesel Oxidation catalysts (DOC) and catalyzed DPFs (CDPF) is widely used for its simplicity and low cost, which is generally combined with the active regeneration of exhaust fuel injection. This study investigated a DOC-CDPF system with exhaust fuel injection upstream of the DOC. The system was integrated with a 7-liter diesel engine whose engine-out PM emission was below the Euro IV level and tested on an engine dynamometer. PM and PN concentrations were measured based on the Particle Measurement Programme (PMP), and the number/size spectrum for particles was obtained by a Differential Mobility Spectrometer (DMS). The filtration efficiency of DPF on PN was higher than 99% in ESC test, while the efficiency on PM was only 58%. During the active regeneration, a certain amount of diesel fuel was injected into the tailpipe and then oxidized in the DOC.
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