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Viewing 1 to 30 of 2357
2016-05-18 ...
  • May 18-20, 2016 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Fuel composition has had to change with the advent of more stringent emission regulations. Reformulated gasoline (RFG), for example, is vastly different from gasoline of even ten years ago. Tightening regulations on diesel emissions will dramatically change both diesel fuel and engine design. This three-day seminar will review the fundamentals of motor fuels, combustion and motor power generation. The primary content of the course provides a basic introduction to the technology, performance, evaluation, and specifications of current gasoline, diesel, and turbine fuels.
2016-04-05
Technical Paper
2016-01-1069
Masayoshi Otaka, Taro Kasahara, Kenichi Komaba
Abstract As a means of further improving combustion efficiency of gasoline engine, an increase in compression ratio, which enhances the risk of knocking, is thinkable. To optimize engine combustion parameters, a technology that can precisely detect knocking is desirable. Presently skillful experts have been evaluating knocking subjectively by listening to radiation noise so far. The authors developed a device that can precisely detect knocking by means of processing sound signals, which are captured by a high-performance microphone that is sensitive in the wide frequency range. Shock waves induced by knocking cause in-cylinder gas vibrations that emits metallic hit noises from the outer engine wall. We studied how to identify the feature values of frequency characteristics when knocking occurs, under the assumption that the engine radiation noise includes more than 2nd-order harmonic components with respect to the basic frequency of the in-cylinder gas vibration mode.
2016-04-05
Technical Paper
2016-01-1016
Yolanda Bravo, Carmen Larrosa, Jose Lujan, Héctor Climent, Manuel Rivas
Abstract Spark ignition (SI) engines are increasing their popularity worldwide since compression ignition (CI) engines have been struggling to comply with new pollutant emission regulations. At the moment, downsizing is the main focus of research on SI engines, decreasing their displacement and using a turbocharging system to compensate this loss in engine size. Exhaust gas recirculation is becoming a popular strategy to address two main issues that arise in heavily downsized turbocharged engines at full load operation: knocking at low engines speeds and fuel enrichment at high engine speeds to protect the turbine. In this research work, a fuel consumption optimization for different operating conditions was performed to operate with a cooled EGR loop, with gasoline and E85. Thus, the benefits of exhaust gas recirculation are proven for a SI gasoline turbocharged direct injection engine.
2016-04-05
Technical Paper
2016-01-1009
Xin Wang, Yunshan Ge, Chuanzhen Zhang, Jia Liu, Zihang Peng, Huiming Gong
Abstract Along with the booming expansion of private car preservation, many Chinese cities are now struggling with hazy weather and ground-level ozone contamination. Although central government has stepped up efforts to purify skies above China, counter-strategies to curb ground-level ozone is comparatively weak. By using maximum incremental reactivity (MIR) method, this paper estimated the ozone forming potential for twenty-five Euro-3 to Euro-5 passenger cars burning conventional gasoline, methanol-gasoline, ethanol-gasoline, neat methanol and compressed natural gas (CNG). The results showed that, for all the fuel tested, VOC/NOx ratios and SR values decreased with the upgrading of emission standard. Except for Euro-3 M100 and Euro-4 M85, SR values for alternative fuel were to different degrees smaller than those for gasoline. When the emission standard was shifted from Euro-4 to Euro-5, OFP values estimated for gasoline vehicle decreased.
2016-04-05
Technical Paper
2016-01-1343
Vivek Yadav, Krishnan Karthikeyan, Wasim Akram Shaikh, Ganesh Dacharum, Keerthi B. M.
Abstract Super-knocking event generates high pressure pulse in gasoline engine, the predominant failure mode in these cases is connecting rod buckling. Two major factors which affects the bucking strength of connecting rod are shank dimensions and load offset in crankpin axis. There are standard methods available for calculating buckling strength of connecting rod such as Johnson’s buckling equation, Eigenvalue method, Merchant-Rankine formula etc. Each of these methods have pros and cons. But no method caters to all the considerations accurately such as section variation in shank, load offsets, local material plasticity and geometric nonlinearity as in bending preceded by buckling. In present paper, a new methodology is developed using FEA to evaluate the connecting rod buckling strength and post buckling deformation. Comparison with eigenvalue method and theoretical results are presented. Study related to buckling load sensitivity for load offset is also presented.
2016-04-05
Technical Paper
2016-01-1277
Monis Alam, Ashish Jaiswal, Jatin Agarwal, Ketan Yadav, Naveen Kumar
Abstract Gasoline has been the major fuel in transportation, its good calorific value and high volatility have made it suitable for use in different injection methods. The drastic increase in use of carbon based fuels has led to increase in harmful emissions, thus resulting in implementation of stricter emissions norms. These harmful emissions include carbon monoxide and NOx. To meet the new norms and reduce the harmful emissions, better techniques have to be implemented to achieve better combustion of gasoline and reduce the amount of carbon monoxide in the exhaust. One such way of doing this is by enriching gasoline with hydrogen. Due to its low activation energy and high calorific value, the high energy released from hydrogen can be used to achieve complete combustion of gasoline fuel. However, there are certain drawbacks to the use of hydrogen in spark ignition engine, knocking and overheating of engine parts being the major problems.
2016-04-05
Technical Paper
2016-01-1281
Jatin Agarwal, Monis Alam, Ashish Jaiswal, Ketan Yadav, Naveen Kumar
Abstract The continued reliance on fossil fuel energy resources is not sufficient to cater to the current energy demands. The excessive and continuous use of crude oil is now recognized as unviable due to its depleting supplies and elevating environmental degradation by increased emissions from automobile exhaust. There is an urgent need for a renewable and cleaner source of energy to meet the stringent emission norms. Hythane is a mixture of 20% hydrogen and 80% methane. It has benefits of low capital and operating costs and is a cleaner alternative than crude oil. It significantly reduces tailpipe emissions and is the cheapest way to meet new emission standards that is BS-IV. Hythane produces low carbon monoxide (CO), carbon dioxide (CO2) and hydrocarbons (HC) on combustion than crude oil and helps in reduction of greenhouse gases.
2016-04-05
Journal Article
2016-01-0806
James Sevik, Michael Pamminger, Thomas Wallner, Riccardo Scarcelli, Ronald Reese, Asim Iqbal, Brad Boyer, Steven Wooldridge, Carrie Hall, Scott Miers
Abstract Interest in natural gas as a fuel for light-duty transportation has increased due to its domestic availability and lower cost relative to gasoline. Natural gas, comprised mainly of methane, has a higher knock resistance than gasoline making it advantageous for high load operation. However, the lower flame speeds of natural gas can cause ignitability issues at part-load operation leading to an increase in the initial flame development process. While port-fuel injection of natural gas can lead to a loss in power density due to the displacement of intake air, injecting natural gas directly into the cylinder can reduce such losses. A study was designed and performed to evaluate the potential of natural gas for use as a light-duty fuel. Steady-state baseline tests were performed on a single-cylinder research engine equipped for port-fuel injection of gasoline and natural gas, as well as centrally mounted direct injection of natural gas.
2016-04-05
Journal Article
2016-01-0785
Martin Kirsten, Gerhard Pirker, Christoph Redtenbacher, Andreas Wimmer, Franz Chmela
Abstract As emission limits become increasingly stringent and the price of gaseous fuels decreases, more emphasis is being placed on promoting gas engines. In the field of large engines for power generation, dual fuel combustion concepts that run on diesel/natural gas are particularly attractive. Knock in diesel/natural gas dual fuel engines is a well known yet not fully understood complex phenomenon that requires consideration in any attempt to increase load and efficiency. Thus combustion concept development requires a reliable yet robust methodology for detecting knock in order to ensure knock-free engine operation. Operating parameters such as rail pressure, start of injection and amount of diesel injected are the factors that influence oscillations in the in-cylinder pressure trace after the start of combustion. Oscillations in the pre-mixed combustion phase, or ringing, are caused by the rapid conversion of large parts of the injected diesel.
2016-04-05
Journal Article
2016-01-0601
Sebastiano Breda, Alessandro D'Adamo, Stefano Fontanesi, Nicola Giovannoni, Francesco Testa, Adrian Irimescu, Simona Merola, Cinzia Tornatore, Gerardo Valentino
Abstract The occurrence of knock is the most limiting hindrance for modern Spark-Ignition (SI) engines. In order to understand its origin and move the operating condition as close as possible to onset of this potentially harmful phenomenon, a joint experimental and numerical investigation is the most recommended approach. A preliminary experimental activity was carried out at IM-CNR on a 0.4 liter GDI unit, equipped with a flat transparent piston. The analysis of flame front morphology allowed to correlate high levels of flame front wrinkling and negative curvature to knock prone operating conditions, such as increased spark timings or high levels of exhaust back-pressure. In this study a detailed CFD analysis is carried out for the same engine and operating point as the experiments. The aim of this activity is to deeper investigate the reasons behind the main outcomes of the experimental campaign.
2016-04-05
Journal Article
2016-01-0689
Magnus Sjöberg, Wei Zeng
Abstract Well-mixed lean or dilute SI engine operation can provide efficiency improvements relative to that of traditional well-mixed stoichiometric SI operation. However, the realized gains depend on the ability to ensure stable, complete and fast combustion. In this work, the influence of fuel type is examined for gasoline, E30 and E85. Several enabling techniques are compared. For enhanced ignition stability, a multi-pulse (MP) transient plasma ignition system is compared to a conventional high-energy inductive spark ignition system. Combined effects of fuel type and intake-gas preheating are examined. Also, the effects of dilution type (air or N2-simulated EGR) on lean efficiency gains and stability limits are clarified. The largest efficiency improvement is found for lean gasoline operation using intake preheating, showing the equivalent of a 20% fuel-economy gain relative to traditional non-dilute stoichiometric operation.
2016-04-05
Technical Paper
2016-01-0678
Haifeng Lu, Jun Deng, Zongjie Hu, Zhijun Wu, Liguang Li, Fangen Yuan, Degang Xie, Shuang Yuan, Yuan Shen
Abstract This research was concerned with the use of Exhaust Gas Recirculation (EGR) improving the fuel economy over a wide operating range in a downsized boosted gasoline engine. The experiments were performed in a 1.3-Litre turbocharged PFI gasoline engine, equipped with a Low Pressure (LP) water-cooled EGR system. The operating conditions varied from 1500rpm to 4000rpm and BMEP from 2bar to 17bar. Meanwhile, the engine’s typical operating points in NEDC cycle were tested separately. The compression ratio was also changed from 9.5 to 10.5 to pursue a higher thermal efficiency. A pre-compressor throttle was used in the experiment working together with the EGR loop to keep enough EGR rate over a large area of the engine speed and load map. The results indicated that, combined with a higher compression ratio, the LP-EGR could help to reduce the BSFC by 9∼12% at high-load region and 3∼5% at low-load region.
2016-04-05
Journal Article
2016-01-0703
Yoshihiro Imaoka, Kiyotaka Shouji, Takao Inoue, Toru Noda
Abstract Technologies for improving the fuel economy of gasoline engines have been vigorously developed in recent years for the purpose of reducing CO2 emissions. Increasing the compression ratio is an example of a technology for improving the thermal efficiency of gasoline engines. A significant issue of a high compression ratio engine for improving fuel economy and low-end torque is prevention of knocking under a low engine speed. Knocking is caused by autoignition of the air-fuel mixture in the cylinder and seems to be largely affected by heat transfer from the intake port and combustion chamber walls. In this study, the influence of heat transfer from the walls of each part was analyzed by the following three approaches using computational fluid dynamics (CFD) and experiments conducted with a multi-cooling engine system. First, the temperature rise of the air-fuel mixture by heat transfer from each part was analyzed.
2016-04-05
Technical Paper
2016-01-0704
Jacob McKenzie, Wai K. Cheng
Abstract The combustion process after auto-ignition is investigated. Depending on the non-uniformity of the end gas, auto-ignition could initiate a flame, produce pressure waves that excite the engine structure (acoustic knock), or result in detonation (normal or developing). For the “acoustic knock” mode, a knock intensity (KI) is defined as the pressure oscillation amplitude. The KI values over different cycles under a fixed operating condition are observed to have a log-normal distribution. When the operating condition is changed (over different values of λ, EGR, and spark timing), the mean (μ) of log (KI/GIMEP) decreases linearly with the correlation-based ignition delay calculated using the knock-point end gas condition of the mean cycle. The standard deviation σ of log(KI/GIMEP) is approximately a constant, at 0.63. The values of μ and σ thus allow a statistical description of knock from the deterministic calculation of the ignition delay using the mean cycle properties
2016-04-05
Technical Paper
2016-01-0701
Katsuya Matsuura, Keito Nakano, Keisuke Shimizu, Norimasa Iida, Yoshihisa Sato
Abstract Knock is a factor hindering enhancement of the thermal efficiency of spark ignition engines, and is an unsteady phenomenon that does not necessarily occur each cycle. In addition, the heat release history of the flame also fluctuates from cycle to cycle, and the auto-ignition process of the unburned mixture (end-gas), compressed by the global increase in pressure due to release of chemical energy, is affected by this fluctuation. Regarding auto-ignition of the end-gas, which can be the origin of knock, this study focused on the fluctuation of the flame heat release pattern, and used a zero-dimensional (0D) detailed chemical reaction calculation in an attempt to analyze and examine the consequence on the end-gas compression and auto-ignition process of changes in the i) start of combustion, ii) combustion duration and iii) center of heat release of the flame.
2016-04-05
Technical Paper
2016-01-0699
Jacob McKenzie, Wai K. Cheng
Abstract An ignition delay correlation encompassing the effects of temperature, pressure, residual gas, EGR, and lambda (on both the rich and lean sides) has been developed. The procedure uses the individual knocking cycle data from a boosted direct injection SI engine (GM LNF) operating at 1250 to 2000 rpm, 8-14 bar GIMEP, EGR of 0 to 12.5%, and lambda of 0.8 to 1.3 with a certification fuel (Haltermann 437, with RON=96.6 and MON=88.5). An algorithm has been devised to identify the knock point on individual pressure traces so that the large data set (of some thirty three thousand cycles) could be processed automatically. For lean and for rich operations, the role of the excess fuel, air, and recycled gas (which has excess air in the lean case, and hydrogen and carbon monoxide in the rich case) may be treated effectively as diluents in the ignition delay expression.
2016-04-05
Technical Paper
2016-01-0702
Gautam Kalghatgi, Kai Morganti, Ibrahim Algunaibet, Mani Sarathy, Robert Dibble
An earlier paper has shown the ability to predict the phasing of knock onset in a gasoline PFI engine using a simple ignition delay equation for an appropriate surrogate fuel made up of toluene and PRF (TPRF). The applicability of this approach is confirmed in this paper in a different engine using five different fuels of differing RON, sensitivity, and composition - including ethanol blends. An Arrhenius type equation with a pressure correction for ignition delay can be found from interpolation of previously published data for any gasoline if its RON and sensitivity are known. Then, if the pressure and temperature in the unburned gas can be estimated or measured, the Livengood-Wu integral can be estimated as a function of crank angle to predict the occurrence of knock. Experiments in a single cylinder DISI engine over a wide operating range confirm that this simple approach can predict knock very accurately.
2016-04-05
Technical Paper
2016-01-0700
Johannes Mutzke, Blane Scott, Richard Stone, John Williams
Abstract Knocking combustion places a major limit on the performance and efficiency of spark ignition engines. Spontaneous ignition of the unburned air-fuel mixture ahead of the flame front leads to a rapid release of energy, which produces pressure waves that cause the engine structure to vibrate at its natural frequencies and produce an audible ‘pinging’ sound. In extreme cases of knock, increased temperatures and pressures in the cylinder can cause severe engine damage. Damage is thought to be caused by thermal strain effects that are directly related to the heat flux. Since it will be the maximum values that are potentially the most damaging, then the heat flux needs to be measured on a cycle-by-cycle basis. Previous work has correlated heat flux with the pressure fluctuations on an average basis, but the work here shows a correlation on a cycle-by-cycle basis. The in-cylinder pressure and surface temperature were measured using a pressure transducer and eroding-type thermocouple.
2016-04-05
Technical Paper
2016-01-0643
Jian Zhang, Changwen Liu, Fengrong Bi, Yiqiang Pei, Xiaobo Bi
Abstract Knock threshold detection is the key of closed loop control of ignition in gasoline engine, and it is also the difficult point in knock measurement. In this paper, an investigation of knock detection in turbocharged gasoline engine using bispectrum slice and ensemble empirical mode decomposition (EEMD) based on the engine cylinder head vibration signals is presented. By adding some finite amplitude Gaussian white noises to the signal, EEMD keeps the signal continuous in different time span, and therefore the mode mixing inhering in the classical empirical mode decomposition (EMD) method is alleviated. Power spectrum density (PSD) estimation is used to determine the band range of the resonance frequency generated by knock component. EEMD is used to decompose the original signals, the time-frequency characteristics of the Intrinsic Mode Functions (IMF) are analyzed using Continues Wavelet Transform (CWT) due to its excellent time-frequency resolution.
2016-04-05
Journal Article
2016-01-0666
Guillaume Bourhis, Jean-Pascal Solari, Virginie Morel, Roland Dauphin
Abstract The efficiency of spark ignition (SI) engines is usually limited by the occurrence of knock, which is linked to fuel octane number. If running the engine at its optimal efficiency requires a high octane number at high load, a lower octane number can be used at low load. Saudi Aramco, along with its long-term partner IFP Energies nouvelles, has been developing a synergistic fuel engine system where the engine is fed by fuel with an octane number adjusted in real time, on an as needed basis, while running at its optimal efficiency. Two major steps are identified to develop this “Octane on Demand” (OOD) concept: First, characterize the octane requirement needed to run the engine at its optimal efficiency over the entire map. Then, select the best dual fuel combination, including a base fuel and an octane booster to fit this concept.
2016-04-05
Technical Paper
2016-01-0087
Fengrong Bi, Teng Ma, Jian Zhang
Abstract This paper reports an investigation of knock detection in spark ignition (SI) engines using EEMD-Hilbert transform based on the engine cylinder block vibration signals. Ensemble Empirical Mode Decomposition (EEMD) was used to de-compose the signal and detect knock characteristic. Hilbert transform was used to analysis the frequency information of knock characteristics. The result shows that for cylinder block vibration signals, the EEMD algorithm could extract the knock characteristic (include light knock), and the Hilbert transform result shows that the instantaneous of knock characteristics concentrate in 5000-10000Hz. At last, the knock window is then determined, based on which a new knock intensity evaluation factor K is proposed, and the results show that, the parameter K is reasonable and effective.
2016-04-05
Journal Article
2016-01-0581
Alessandro D'Adamo, Sebastiano Breda, Stefano Fontanesi, Giuseppe Cantore
Abstract Engine knock is emerging as the main limiting factor for modern spark-ignition (SI) engines, facing increasing thermal loads and seeking demanding efficiency targets. To fulfill these requirements, the engine operating point must be moved as close as possible to the onset of abnormal combustion events. The turbulent regime characterizing in-cylinder flows and SI combustion leads to serious fluctuations between consecutive engine cycles. This forces the engine designer to further distance the target condition from its theoretical optimum, in order to prevent abnormal combustion to severely damage the engine components just because of few individual heavy-knocking cycles. A RANS-based model is presented in this study, which is able to predict not only the ensemble average knock occurrence but also a knock probability. This improves the knock tendency characterization, since the mean knock onset alone is a poorly meaningful indication in a stochastic event such as engine knock.
2016-04-05
Technical Paper
2016-01-0748
Vijai Shankar Bhavani Shankar, Muhammad Sajid, Khalid Al-Qurashi, Nour Atef, Issam Alkhesho, Ahfaz Ahmed, Sukho Chung, William Roberts, Kai Morganti, Mani Sarathy
Abstract Primary Reference Fuels (PRFs) - binary mixtures of n-heptane and iso-octane based on Research Octane Number (RON) - are popular gasoline surrogates for modeling combustion in spark ignition engines. The use of these two component surrogates to represent real gasoline fuels for simulations of HCCI/PCCI engines needs further consideration, as the mode of combustion is very different in these engines (i.e. the combustion process is mainly controlled by the reactivity of the fuel). This study presents an experimental evaluation of PRF surrogates for four real gasoline fuels termed FACE (Fuels for Advanced Combustion Engines) A, C, I, and J in a motored CFR (Cooperative Fuels Research) engine. This approach enables the surrogate mixtures to be evaluated purely from a chemical kinetic perspective. The gasoline fuels considered in this study have very low sensitivities, S (RON-MON), and also exhibit two-stage ignition behavior.
2016-04-05
Technical Paper
2016-01-0762
Jihad Badra, Ahmed Elwardany, Jaeheon Sim, Yoann Viollet, Hong Im, Junseok Chang
Abstract Gasoline compression ignition (GCI) engines have been considered an attractive alternative to traditional spark ignition engines. Low octane gasoline fuel has been identified as a viable option for the GCI engine applications due to its longer ignition delay characteristics compared to diesel and in the volatility range of gasoline fuels. In this study, we have investigated the effect of different injection timings at part-load conditions using light naphtha stream in single cylinder engine experiments in the GCI combustion mode with injection pressure of 130 bar. A toluene primary reference fuel (TPRF) was used as a surrogate for the light naphtha in the engine simulations performed here. A physical surrogate based on the evaporation characteristics of the light naphtha has been developed and its properties have been implemented in the engine simulations.
2016-04-05
Journal Article
2016-01-0719
Mattias Mayer, Peter Hofmann, Bernhard Geringer, John Williams, James Moss
Abstract In recent years a new combustion phenomenon called Low-Speed Pre-Ignition (LSPI) occurred, which is the most important limiting factor to exploit further downsizing potential due to the associated peak pressures and thus the huge damage potential. In the past there were already several triggers for pre-ignitions identified, whereat engine oil seems to have an important influence. Other studies have reported that detached oil droplets from the piston crevice volume lead to auto-ignition prior to spark ignition. However, wall wetting and subsequently oil dilution and changes in the oil properties by impinging fuel on the cylinder wall seem to have a significant influence in terms of accumulation and detachment of oil-fuel droplets in the combustion chamber. For this reason, the influence of test fuels with different volatility were investigated in order to verify their influence on wall wetting, detachment and pre-ignition tendency.
2016-04-05
Technical Paper
2016-01-0720
Yan Long, Zhi Wang, Yunliang Qi, Shouzhi Xiang, Guang Zeng, Peng Zhang, Xin He, Ashutosh Gupta, Huifang Shao, Yinhui Wang
Abstract High boost and direct injection are effective ways for energy saving in gasoline engines. However, the occurrence of super-knock at high load has become a main obstacle for further improving power density and fuel economy. It has been known that super-knock can be induced by pre-ignition, and oil droplet auto-ignition is found to be one of the possible mechanisms. In this study, experiments were conducted in a single-cylinder thermal research engine (TRE), in which different types of oil and surrogates were directly injected into the cylinder and then led to pre-ignition and super-knock. The effect of oil injection timing, oil injection quantity, different gasoline and different oil were tested. All the oil in this work could induce pre-ignition, even though their combustion phasing was much later than that in the case of n-hexadecane.
2016-04-05
Technical Paper
2016-01-0721
Andrew B. Mansfield, Elana Chapman, Kenneth Briscoe
Abstract The effects of aromatic content and octane rating of gasoline fuels on stochastic pre-ignition (SPI) behaviors were investigated at typical operating conditions using a modern 2.0 L turbocharged engine. In-cylinder pressure time history measurements made during a speed-load test sequence designed to stimulate SPI were used to determine both the frequency of SPI occurrence and the in-cylinder peak pressure during such events. Six fuels were tested with varying levels of aromatic content (15 - 35% by vol.) and two octane rating levels (∼88 & 94 anti-knock index). The engine was operated using a production-intent calibration with equivalence ratio near one. Pressure and temperature in the intake manifold were held constant near two bar and 35°C respectively. Significant SPI activity was observed, with abnormal event frequencies up to ∼1 SPI event per 1,000 engine cycles and in-cylinder peak pressures up to ∼200 bar.
2016-04-05
Technical Paper
2016-01-0716
Doyle Boese, Andrew Ritchie, Anne W. Young
Abstract In recent years, an abnormal combustion phenomenon called low-speed pre-ignition (LSPI) has arisen from the downsizing of gasoline engines in order to improve fuel economy and comply with global CO2 legislation. The type and quality of the fuel and lubricant has been found to influence LSPI occurrence rates. A methodology for studying LSPI has been implemented, and a rigorous statistical approach for studying the data from a stationary engine test can provide consistent results as shown in Part 1 of the series. LSPI events can be determined by an iterative statistical procedure based on calculating the mean and standard deviation of peak pressure (PP) and crank angle location of 2% mass fraction burned (MFB02) data, determining cycles with parameters which exceeded n standard deviations from the mean and identifying outliers. Outliers for the PP and MFB02 metrics are identified as possible LSPI events.
2016-04-05
Technical Paper
2016-01-0833
Lei Meng, Yuqiang Li, Karthik Nithyanandan, Timothy Lee, Chunnian Zeng, Chia-Fon Lee
Abstract To face the challenges of fossil fuel shortage and air pollution problems, there is growing interest in the potential usage of alternative fuels such as bio-ethanol and bio-butanol in internal combustion engines. The literature shows that the acetone in the Acetone-Butanol-Ethanol (ABE) blends plays an important part in improving the combustion performance and emissions, owing to its higher volatility. In order to study the effects of acetone addition into commercial gasoline, this study focuses on the differences in combustion, performance and emission characteristics of a port-injection spark-ignition engine fueled with pure gasoline (G100), ethanol-containing gasoline (E30) and acetone-ethanol-gasoline blends (AE30 at A:E volumetric ratio of 3:1). The tests were conducted at 1200RPM with the default calibration (for gasoline), at 3 bar and 5 bar BMEP under various equivalence ratios.
2016-04-05
Journal Article
2016-01-0834
Arjun Prakash, Roger Cracknell, Vinod Natarajan, David Doyle, Aaron Jones, Young Suk Jo, Matthew Hinojosa, Peter Lobato
Octane appetite of modern engines has changed as engine designs have evolved to meet performance, emissions, fuel economy and other demands. The octane appetite of seven modern vehicles was studied in accordance with the octane index equation OI=RON-KS, where K is an operating condition specific constant and S is the fuel sensitivity (RONMON). Engines with a displacement of 2.0L and below and different combinations of boosting, fuel injection, and compression ratios were tested using a decorrelated RONMON matrix of eight fuels. Power and acceleration performance were used to determine the K values for corresponding operating points. Previous studies have shown that vehicles manufactured up to 20 years ago mostly exhibited negative K values and the fuels with higher RON and higher sensitivity tended to perform better.
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