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2014-10-29
Article
Think you know about motor oils and the latest technologies within them? Read this article.
2014-10-29
Article
China’s commercial-vehicles industry is poised for a transformation as suppliers focus on services and clean energy. These changes are occurring amid market shifts as China attempts to reduce pollution and congestion in cities.
2014-10-29
Article
SAE International recently published the J2880 - Recommended Green Racing Protocols. The aims of J2880 are to: • Provide sanctioning bodies with recommendations to help them align competition rules with the objectives of sustainable transportation • Support environmentally responsible and sustainable technology that is transferable to production vehicles • Promote environmentally friendly operations of motorsports venues, competition events, and racing team facilities • Assist sanctioning bodies in establishing a roadmap to increase green initiatives.
2014-10-22
Book
The new Bosch Automotive Handbook, now in its 9th English edition, has been completely revised and enhanced to include the most recent developments in automotive technology. About 200 specialist authors contributed to this new version of every engineer’s must-have reference. The book's format has been revised: it is now 20 percent longer and wider, as this allows for a larger font size. This makes the texts and graphics easier to read. The index has been strongly expanded to make looking up technical terms easier. The Bosch Automotive Handbook is a best-seller, with a broad global readership. Students of engineering programs consult it, as do researchers and engineers in the automotive industry. Mechanics who are studying to become master craftsmen also use it as a reference work. Experts trust the well-founded and extensive expertise that can be found in the classic. The Bosch Automotive Handbook is widely regarded around the world as a standard work for automotive technology.
2014-10-21
Article
General Motors claims that its 2015 Chevrolet Bi-fuel Impala running on gasoline or CNG (compressed natural gas) will be the only bi-fuel-capable sedan on the market to offer a factory warranty. It is slated to go on sale later this year at a starting price of $38,210.
2014-10-20
Article
VCC’s series of IP67- and NEMA 6P-rated panel-mount indicators are designed with a wide viewable angle that delivers bright visibility even in direct sunlight.
2014-10-13
Article
Researchers discover factor that could have significant impact on industrial biofuel production.
2014-10-13
Technical Paper
2014-01-2762
Pradip Lingfa, Pranab Das, Lalit Das, Satya Naik
Abstract In the present experimental investigations the influence of injector opening pressures and injection timings on the engine performance and exhaust emissions of a naturally aspirated single cylinder diesel engine has been investigated. The test were conducted with four different fuels, namely diesel and Tung biodiesel blends (TB10, TB15, TB20 and TB50) at three different injector opening pressures (150 bar, 200 bar and 250 bar) respectively. Fuel injection opening pressures were varied by changing the spring tension of the needle valve of injector nozzle. The three different injection timings (Standard timing at 23° BTDC, Retarded Timing of 21° BTDC and Advanced Timing of 25° BTDC) were used. The injection timings were varied by changing the thickness of the shim. The entire tests were conducted at the constant engine speed of 1500 rpm under various load conditions.
2014-10-13
Technical Paper
2014-01-2570
Karthik Puduppakkam, Chitralkumar Naik, Ellen Meeks, Christian Krenn, Roswitha Kroiss, Johannes Gelbmann, Guenther Pessl
Abstract An important goal for CFD simulation in engine design is to be able to predict the combustion behavior as operating conditions are varied and as hardware is modified. Such predictive capability allows virtual prototyping and optimization of design parameters. For low-temperature combustion conditions, such as with high rates of exhaust-gas recirculation, reliable and accurate predictions have been elusive. Soot has been particularly difficult to predict, due to the dependence of soot formation on the fuel composition and the kinetics detail of the fuel combustion. Soot evolution in diesel engines is impacted by fuel and chemistry effects, as well as by spray dynamics and turbulence. In this work, we present a systematic approach to accurately simulate combustion and emissions in a high-performance BMW diesel engine. This approach has been tested and validated against experimental data for a wide range of operating conditions.
2014-10-13
Technical Paper
2014-01-2569
Fabrizio Bonatesta, Salvatore La Rocca, Edward Hopkins, Daniel Bell
Abstract Gasoline Direct Injection engines are efficient devices which are rivaling diesel engines with thermal efficiency approaching the 40% threshold at part load. Nevertheless, the GDI engine is an important source of dangerous ultra-fine particulate matter. The long-term sustainability of this technology strongly depends on further improvement of engine design and combustion process. This work presents the initial development of a full-cycle CFD model of a modern wall-guided GDI engine operated in homogeneous and stoichiometric mode. The investigation was carried out at part-load operating conditions, with early injections during the intake stroke. It included three engine speeds at fixed engine-equivalent load. The spray model was calibrated using test-bed and imaging data from the 7-point high-pressure fuel injectors used in the test engine.
2014-10-13
Technical Paper
2014-01-2552
Tao Yin, Tie Li, Longhua Chen, Bin Zheng, Fei Zhao
Abstract This paper studies the effect of cooled EGR on fuel consumption and anti-knock performance of a boosted port fuel injection (PFI) SI engine. Experimental results show that the cooled EGR increases the thermal efficiency by 2%∼18% depending on the operation conditions. Compared to low load operations, more improvements of the thermal efficiency are obtained at higher loads, primarily owing to the enhanced anti-knock performance, advanced combustion phasing, elimination of fuel-rich operations as well as reduced heat transfer loss with cooled EGR. The anti-knock performance of cooled EGR provides further potential to improve the thermal efficiency by increasing the compression ratio. To this end, a 1-D thermodynamic model of the engine is built and calibrated using the GT-Power code. A knock prediction correlation considering EGR is developed and validated with the experimental data.
2014-10-13
Technical Paper
2014-01-2564
Andrew Smallbone, Amit Bhave, Peter Man
Abstract This paper demonstrates how the validation and verification phase of prototype development can be simplified through the application of the Model Development Suite (MoDS) software by integrating advanced statistical and numerical techniques. The authors have developed and present new numerical and software integration methods to support a) automated model parameter estimation (model calibration) with respect to experimental data and, b) automated global sensitivity analysis through using a High Dimensional Model Representation (HDMR). These methods are demonstrated at 1) a component level by performing systematic parameter estimation of various friction models for heavy-duty IC engine applications, 2) at a sub-component level by performing a parameter estimation for an engine performance model, and 3) at a system level for evaluating fuel efficiency losses (and CO2 sources) in a vehicle model over 160 ‘real-world’ and legislated drive cycles.
2014-10-13
Technical Paper
2014-01-2668
Maobin Liu, Bang-Quan He, Hua Zhao
Biobutanol, i.e. n-butanol, as a second generation bio-derived alternative fuel of internal combustion engines, can facilitate the energy diversification in transportation and reduce carbon dioxide (CO2) emissions from engines and vehicles. However, the majority of research was conducted on spark-ignition engines fuelled with n-butanol and its blend with gasoline. A few investigations were focused on the combustion and exhaust emission characteristics of homogeneous charge compression ignition (HCCI) engines fuelled with n-butanol-gasoline blends. In this study, experiments were conducted in a single cylinder four stroke port fuel injection HCCI engine with fully variable valve lift and timing mechanisms on both the intake and exhaust valves. HCCI combustion was achieved by employing the negative valve overlap (NVO) strategy while being fueled with gasoline (Bu0), n-butanol (Bu100) and their blends containing 30% n-butanol by volume (Bu30).
2014-10-13
Technical Paper
2014-01-2658
Denis W. Gill, Herwig Ofner, Carsten Stoewe, Karl Wieser, Ernst Winklhofer, Masaaki Kato, Takamasa Yokota, Jost Weber
Abstract For nearly twenty years, DiMethyl Ether has been known to be an outstanding fuel for combustion in diesel cycle engines. Not only does it have a high Cetane number, it burns absolutely soot free and produces lower NOx exhaust emissions than the equivalent diesel. However, the physical properties of DME such as its low viscosity, lubricity and bulk modulus have negative effects for the fuel injection system, which have both limited the achievable injection pressures to about 500 bar and DME's introduction into the market. To overcome some of these effects, a common rail fuel injection system was adapted to operate with DME and produce injection pressures of up to 1000 bar. To understand the effect of the high injection pressure, tests were carried out using 2D optically accessed nozzles. This allowed the impact of the high vapour pressure of DME on the onset of cavitation in the nozzle hole to be assessed and improve the flow characteristics.
2014-10-13
Technical Paper
2014-01-2659
Haifeng Liu, Zunqing Zheng, Lang Yue, Lingcun Kong, Mingfa Yao
Abstract To investigate the effects of fuel volatility on combustion and emissions in a diesel engine, a high-volatility fuel of n-heptane was blended into diesel fuel with different volumetric fractions (0%, 40%, 70%, 100%). A wide range of EGR rates from 0% to 65% were investigated, which covered both the conventional diesel combustion and low temperature combustion. Experiments under two engine load conditions, ∼5.2 bar and ∼10.5 bar gross IMEP were performed at 1500 rpm. The injection timing was fixed at 8°CA BTDC for all test cases. Results show that even if the ignition delay and combustion duration are nearly the same for all tested fuels, the premixed combustion fractions are increased for higher volatility fuels due to the improvement on mixing process during the ignition delay period. The indicated specific fuel consumption is decreased as using high-volatility fuels. The effect of fuel volatility on soot emissions depends on engine loads.
2014-10-13
Technical Paper
2014-01-2646
Siva Subramanian Ravishankar, Aayush Mehrotra, Ghodke Pundlik Rambhaji, Simhachalam Juttu
Abstract One of the major challenges for automotive industry today is to reduce tailpipe emission without compromising on fuel economy especially with the EURO 6, RDE, LEV III emissions and CO2 norms coming up. In case of diesel engines, with the emission norms becoming stringent more and more, it's difficult to improve tradeoff between NOx and PM emissions. After treatment systems give some edge in terms of tail pipe emission reduction but not on the cost, fuel economy and system simplicity front. For diesel engines the compression ratio and design of the bowl geometry plays a crucial role in controlling emission and CO2. The target was to achieve EURO 6 tailpipe emissions with minimum dependency on after treatment. With the target after treatment conversion efficiency the engine out targets were framed. A study of different bowl geometries were made that would help achieve this target of improving reduced engine out emissions.
2014-10-13
Technical Paper
2014-01-2649
Agnese Magno, Ezio Mancaruso, Bianca Maria Vaglieco
Abstract The aim of this study is to investigate the combustion process and pollutant formation in a small compression ignition engine. The engine is a prototype for quadricycles. It was designed to comply with Euro 4 emission standard that is a future regulation for this type of vehicles. Two optical accesses for endoscopes were realized in the first cylinder to investigate the combustion process. Two-color pyrometry method was applied to combustion images in order to detect the flame temperature and the soot concentration. The engine ran with a biodiesel, the rapeseed methyl ester, and a conventional diesel fuel. Operating conditions at the engine speed of 2000 rpm at full and medium load were tested. NOx emissions were measured at exhaust. A smoke meter was used to determine the particulate matter concentration. The sizing and the counting of the particles were performed by means of an engine exhaust particle sizer spectrometer.
2014-10-13
Technical Paper
2014-01-2647
S. Reifarth, E. Kristensson, J. Borggren, A. Sakowitz, H.-E. Angstrom
Abstract The use of EGR for NOX reduction is today a standard technology for diesel engines. The mixing of air and EGR is an important issue, especially for high-pressure EGR-systems. An uneven distribution of EGR between the cylinders can lead to higher overall engine emissions when some cylinders produce more soot, others more NOX than they would with a perfectly even distribution. It is therefore important to understand the processes that control the mixing between air and EGR. The mixing is influenced by both the geometry of the mixing area and the pulsating nature of the flow. The aim of this work is to point out the high importance of the pulses present in the EGR-flow. By simulation in 1-D and 3-D as well as by a fast measurement method, it is shown that the EGR is transported in the air flow in packets. This implies that the timing between intake valve opening and the positioning of the EGR packets has a high influence of the distribution of EGR between the cylinders.
2014-10-13
Technical Paper
2014-01-2653
XiaoDan Cui, Beini Zhou, Hiroki Nakamura, Kusaka Jin, Yasuhiro Daisho
Abstract The objective of the present research was to analyze the effects of using oxygenated fuels (FAMEs or biodiesel fuels) on injected fuel spray and soot formation. A 3-D numerical study which using the KIVA-3V code with modified chemical and physical models was conducted. The large-eddy simulation (LES) model and KH-RT model were used to simulate fuel spray characteristics. To predict soot formation processes, a model for predicting gas-phase polycyclic aromatic hydrocarbons (PAHs) precursor formation was coupled with a detailed phenomenological particle formation model that included soot nucleation from the precursors, surface growth/oxidation and particle coagulation. The calculated liquid spray penetration results for all fuels agreed well with the measured data. The spray measurements were conducted using a constant volume chamber (CVC), which can simulate the ambient temperature and density under real engine conditions.
2014-10-13
Technical Paper
2014-01-2651
Vipul Vibhanshu, Ashish Karnwal, Amar Deep, Naveen Kumar
The rising cost and limited availability of crude oil in international market has provided an opportunity to look for substitute of fossil fuel. Scientists all over the world are experimenting on variety of renewable fuels for meeting the future energy demands. Bio origin fuels are fast becoming potential alternative resources to replace the fossil fuels. The vegetable oils, derived from oil seed crops have got 90 to 95% energy value of diesel on volume basis, comparable cetane number and can substitute upto 20% (v/v) of diesel fuel. Mahua seed oil is common ingredient of hydrogenated fat. Two-step transesterification process was employed to synthesize biodiesel from Mahua Oil (Madhuca-indica) and analysis of Physico-chemical properties as well as the combustion, performance and emission characteristics was done by taking 10, 20 and 100 % blend with diesel. The physico-chemical properties of the blends were found to be comparable to diesel.
2014-10-13
Journal Article
2014-01-2637
Katsufumi Kondo, Junya Takahashi, Tetsuya Aizawa
Abstract Wall-deposition of soot particles occurs due to the interaction between spray flame and cylinder liner wall/piston surface, which can potentially affect soot morphology after the in-flame formation/oxidation processes and before the exit from engine cylinder. In order to investigate these effects, flame wall impingement was simulated in a constant volume combustion vessel and thermophoretic soot sampling was conducted for Transmission Electron Microscopic analysis. A TEM grid for the sampling was exposed to a single-shot diesel spray flame multiple times and the variation of soot morphology (concentration, primary particle diameter and aggregate gyration radius) among the multiple exposures was compared. Furthermore, a newly designed impingement-type sampler vertically exposed the grid to the spray flame and sampled soot particles under different boundary condition from that of conventionally used skim-type sampler.
2014-10-13
Technical Paper
2014-01-2644
S. Reifarth, V. Rajagopal, K. Gritzun, H.-E. Angstrom
Abstract The distribution of EGR between the cylinders of an internal combustion engine has been shown to have large impact on the engine emissions. Especially at high EGR, the combustion reacts sensibly to variations in the EGR-rate. A cylinder that receives excessive EGR produces soot emissions while a cylinder with too little EGR has increased NOX-formation. It is therefore important to have knowledge about the mixing of air and EGR in an engine. This study compares two different EGR-mixing measurement methods. The first is based on CO2 measurement with standard probes, placed at 36 different locations in the intake manifold of the engine. The second method uses a laser beam and a detector to gain information about the mixing with a high time-resolution. Additionally, 1-D simulations are used to gain information about the mixing process. To vary the mixing process on the engine, two different air/EGR mixers are used and their mixing performance is evaluated.
2014-10-13
Technical Paper
2014-01-2645
J. Balaji, Ganesh Prasad M. V., L. Navaneetha Rao, Balaji Bandaru, A. Ramesh
Abstract This study deals with the development of an internal EGR (Exhaust Gas Recirculation) system for NOx reduction on a six cylinder, turbocharged intercooled, off-road diesel engine based on a modified cam with secondary lift. One dimensional thermodynamic simulation model was developed using a commercially available code. MCC heat release model was refined in the present work by considering wall impingement of the fuel as given by Lakshminarayanan et al. The NOx prediction accuracy was improved to a level of 90% by a generic polynomial fit between air excess ratio and prediction constants. Simulation results of base model were correlating to more than 95% with experimental results for ISO 8178 C1 test cycle. Parametric study of intake and exhaust valve events was conducted with 2IVO (Secondary Intake Valve Opening) and 2EVO (Secondary Exhaust Valve Opening) methods. Combinations of different opening angles and lifts were chosen in both 2IVO and 2EVO methods for the study.
2014-10-13
Journal Article
2014-01-2642
Masaki Kuribayashi, Yuta Mizutani, Yutaro Ishizuka, Natsuki Taki, Tetsuya Aizawa
Abstract For better understanding of soot formation and oxidation processes in diesel combustion, effects of ambient oxygen concentration on in-flame diesel soot particle properties including concentration, size, number density and morphology were investigated in a constant volume combustion vessel via simultaneous LII (Laser-Induced Incandescence) / LS (Laser Scattering) imaging techniques and TEM (Transmission Electron Microscopy) analysis. An analysis of LII and LS images yielded 2-dimensional distribution images of concentration, size and number density of soot particles in diesel spray flame, based on a practical assumption that LII and LS signals are proportional to the soot particle size to the power of 3 and 6, respectively.
2014-10-13
Technical Paper
2014-01-2635
Jing Tian, Zhongchang Liu, Yongqiang Han, Zhaojie Shen, Jiangwei Liu, Kang Li
Abstract In order to improve the performance of low temperature combustion of diesel engines to achieve ultra-low emissions and load condition expansions, exhaust gas recirculation (EGR) stratification in the cylinder was proposed to further intensify local EGR concentration and reduce the amount of EGR to acquire high average oxygen concentration within cylinder. In this study, the intake/exhaust port and combustion chamber models were explored by CFD software on a four-valve HD diesel engine, and fresh air and EGR respectively replaced by O2 and CO2 were introduced with division and timing intake strategies during the intake process for stratification optimization.
2014-10-13
Technical Paper
2014-01-2634
Naoto Horibe, Tatsuya Komizo, Takashi Sumimoto, Hao Wang, Takuji Ishiyama
Abstract A series of experiments using a single-cylinder direct injection diesel engine was conducted to investigate the smoke reduction effect of post injection while varying numerous parameters: the post-injection quantity, post-injection timing, injection pressure, main-injection timing, intake pressure, number of injection nozzle orifices, and combustion chamber shape. The experiments were performed under a fixed NOx emission condition by selecting the total injection quantities needed to obtain the predetermined smoke emission levels without post injection. The smoke reduction effects were compared when changing the post injection timing for different settings of the above parameters, and explanations were found for the measured smoke emission trends. The results indicate that close post injection provides lower smoke emission for a combination of a reentrant combustion chamber and seven-hole nozzle.
2014-10-13
Technical Paper
2014-01-2620
Francesco Catapano, Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco
The growing concerns over the pollutant emissions as well as the depletion of fossil fuel led to the research of advanced combustion mode and alternative fuels for the reduction both of fuel consumption and exhaust emissions. The dual-fuel injection system can be used to improve the engine performance and reduce the fossil fuel consumption performing simultaneously a direct-injection (DI) and a port-fuel-injection (PFI) of different fuels. Ethanol is one of the most promising alternative fuels for SI engines. It offers high anti-knock quality because of the high octane number; moreover, being an oxygenated fuel is very effective in particle emissions reduction. On the other hand, it is characterized by lower energy density mainly because of the low lower heating value (LHV). The aim of the paper is the investigation of the ethanol-gasoline dual fuel combustion on engine performance and emissions.
2014-10-13
Technical Paper
2014-01-2610
Ben Leach, Richard Pearson, Rana Ali, John Williams
Abstract Engine downsizing is a key approach employed by many vehicle manufacturers to help meet fleet average CO2 emissions targets. With gasoline engines in particular reducing engine swept volume while increasing specific output via technologies such as turbocharging, direct injection (DI) and variable valve timing can significantly reduce frictional and pumping losses in engine operating areas commonly encountered in legislative drive cycles. These engines have increased susceptibility to abnormal combustion phenomena such as knock due to the high brake mean effective pressures which they generate. This ultimately limits fuel efficiency benefits by demanding use of a lower geometric compression ratio and sub-optimal late combustion phasing at the higher specific loads experienced by these engines.
2014-10-13
Technical Paper
2014-01-2626
Timothy J. Jacobs, Louis Camilli, Matthias Neubauer
Abstract A key element to achieving vehicle emission certification for most light-duty vehicles using spark-ignition engine technology is prompt catalyst warming. Emission mitigation largely does not occur while the catalyst is below its “light-off temperature”, which takes a certain time to achieve when the engine starts from a cold condition. If the catalyst takes too long to light-off, the vehicle could fail its emission certification; it is necessary to minimize the catalyst warm up period to mitigate emissions as quickly as possible. One technique used to minimize catalyst warm up is to calibrate the engine in such a way that it delivers high temperature exhaust. At idle or low speed/low-load conditions, this can be done by retarding spark timing with a corresponding increase in fuel flow rate and / or leaning the mixture. Both approaches, however, encounter limits as combustion stability degrades and / or nitrogen oxide emissions rise excessively.
2014-10-13
Technical Paper
2014-01-2617
Michael Storch, Lars Zigan, Michael Wensing, Stefan Will
Abstract Modern direct injection spark ignition (DISI) engine concepts have the drawback of higher particulate matter emission as compared to port fuel injection concepts. Especially, when driven with biofuels, the operation of DISI engines requires a deeper insight into particulate formation processes. In this study a modern optical accessible DISI engine is used. Pure isooctane, ethanol, E20 (20vol% of ethanol in isooctane) and E85 were investigated as fuels. Simultaneous OH*-chemiluminescence and soot radiation imaging was conducted by a high-speed camera system in order to separate premixed combustion with the sooting combustion. Furthermore, a laser-induced incandescence (LII) sensor was used to measure exhaust elementary carbon mass concentration. Systematically, operation points were chosen, which correspondent to the main sooting mechanisms, poolfire, mixture inhomogeneities and global low air-fuel ratio.
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