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Viewing 1 to 30 of 2374
2017-04-04
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Mixed modes with both flame propagation and slow auto ignition. Distinct from SI knock: autoignition is desired and will not ruin the engine. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, and SACI mode change are invited and will be placed in appropriate sub-sessions. Papers with an emphasis on the modeling aspects of combustion are encouraged to be submitted into PFL 110 or PFL120 modeling sessions.
2016-10-24
Technical Paper
2016-01-9075
Martijn van Essen, Sander Gersen, Gerco van Dijk, Torsten Mundt, Howard Levinsky
Abstract The effects of air humidity on the knock characteristics of fuels are investigated in a lean-burn, high-speed medium BMEP engine fueled with a CH4 + 4.7 mole% C3H8 gas mixture. Experiments are carried out with humidity ratios ranging from 4.3 to 11 g H2O/kg dry air. The measured pressure profiles at non-knocking conditions are compared with calculated pressure profiles using a model that predicts the time-dependent in-cylinder conditions (P, T) in the test engine (“combustion phasing”). This model was extended to include the effects of humidity. The results show that the extended model accurately computes the in-cylinder pressure history when varying the water fraction in air. Increasing the water vapor content in air decreases the peak pressure and temperature significantly, which increases the measured Knock Limited Spark Timing (KLST); at 4.3 g H2O/kg dry air the KLST is 19 °CA BTDC while at 11 g H2O/kg dry air the KLST is 21 °CA BTDC for the same fuel.
2016-10-17
Technical Paper
2016-01-2259
George S. Dodos, Chrysovalanti E. Tsesmeli, Fanourios Zannikos
The fuel supply chain faces the challenges associated with microbial contamination symptoms. Microbial growth is an issue usually known to be associated with middle distillate fuels and biodiesel, however, incidents where microbial populations have been isolated from unleaded gasoline storage tanks have also been recently reported. Alcohols are employed as gasoline components and the use of these oxygenates is growing esp. regarding ethanol, which can be a renewable alternative to gasoline as well. Despite their alleged disinfectant properties, a number of field observations suggests that biodeterioration could be a potential issue in fuel systems handling ethanol-blended gasoline. The impact of alcohol-fuel blends on fuel microbial susceptibility has been the subject of few studies and additional work could contribute to the understanding of this topic. The aim of this study was to assess the effect of alcohols on microbial proliferation in unleaded gasoline fuel.
2016-10-17
Technical Paper
2016-01-2166
Ahfaz Ahmed, Muhammad Waqas, Nimal Naser, Eshan Singh, William Roberts, Sukho Chung, Mani Sarathy
Commercial gasoline fuels contain hundreds of different hydrocarbons, yet despite their dissimilarity in composition they often demonstrate similar octane ratings. It is of fundamental interest to study differences arising in combustion performance of such fuels, specifically fuels have varying physical properties. This investigation is needed to interpret differences in combustion behavior of gasolines showing similar knocking character in a cooperative fuel research engine, but demonstrating different attributes in a direct injection spark ignition (DISI) engines due to the enhanced effects of fuel properties To investigate this scenario two FACE (Fuels for advanced combustion engines) gasolines, FACE F and FACE G with similar Research and Motor octane but differing physical and chemical properties were studied in a DISI engines.
2016-10-17
Technical Paper
2016-01-2170
Raphael Gukelberger, Dennis Robertson, Terrence Alger, Jess Gingrich, Steven Almaraz, Vijayakannan MOHAN
A turbocharged 2.0 L PFI engine was modified to operate in a low-pressure loop and Dedicated EGR (D-EGR®) engine configuration. Both engine architectures were operated with a low and high octane gasoline as well as three ethanol blends. The core of this study focused on examining combustion differences at part and high loads between the selected fuels and also the different engine configurations. Specifically, the impact of the fuels on combustion stability, burn rates, knock mitigation, required ignition energy, and efficiency were evaluated. The results showed that the knock resistance generally followed the octane rating of the fuel. At part loads, the burn rates, combustion stability, and EGR tolerance was marginally improved with the high ethanol blends. When combustion was not knock or stability limited, the efficiency differences between the fuels were negligible. The D-EGR engine was much less sensitive to fuel changes in terms of burn rates than the LPL EGR setup.
2016-10-17
Technical Paper
2016-01-2295
Chunsheng Ji, John Dec, Jeremie Dernotte, William Cannella
Previous work has shown that conventional ignition improvers, 2-ethylhexyl nitrate (EHN) and di-tert-butyl peroxide (DTBP), can be used to enhance the autoignition of a regular-grade E10 gasoline in an HCCI engine at naturally aspirated and moderately boosted conditions (up to 180 kPa absolute) with a constant engine speed of 1200 rpm and a 14:1 compression ratio. The effect of EHN on boosted HCCI combustion is further investigated with a higher compression ratio (16:1) piston over a range of engine speeds (up to 2400 RPM) in the current work. The results show that the higher compression ratio and engine speeds can make the combustion of a regular-grade E10 gasoline somewhat less stable. The addition of EHN improves the combustion stability by allowing combustion phasing to be more advanced for the same ringing intensity.
2016-10-17
Technical Paper
2016-01-2168
Masaharu Kassai, Taisuke Shiraishi, Toru Noda, Mamoru Hirabe, Yoshiki Wakabayashi, Jin Kusaka, Yasuhiro Daisho
For the development of downsized spark ignition (SI) engine, an abnormal combustion issue which is called low speed pre-ignition(LSPI) was recognized and desired to be solved. To explain the too early pre-ignition timing in LSPI, we need to assume some pre-ignition source which is containing something other than fuel. Previously, it have been reported that LSPI can be caused by droplets of fuel and lubricant oil mixture. In this report, ignition behavior of lubricant component containing fuel injected toward premixed fuel-air mixture was experimentally investigated by using rapid compression and expansion machine (RCEM) which can visualize combustion process in cylinder. Various combinations of fuel composition for premixed fuel-air mixture and fraction of base oil, metallic additives, and fuel for injecting droplets were tested.
2016-10-17
Technical Paper
2016-01-2307
Guillaume Bourhis, Jean-Pascal Solari, Roland DAUPHIN, Loic De Francqueville
Efficiency of spark ignition engines is limited towards high loads by the occurrence of knock, which is linked to the octane number of the fuel. Running the engine at its optimal efficiency requires a high octane number at high load whereas a low octane number can be used at low load. Saudi Aramco, along with its long-term partner IFP Energies nouvelles, is developing an “Octane on Demand” (OOD) concept: the fuel octane number is adjusted “on demand” to prevent knock occurrence by adapting the fuel RON injected in the combustion chamber. Thus, the engine cycle efficiency is increased by always keeping combustion phasing at optimum. This is achieved by a dual fuel injection strategy, involving a low-RON base fuel and a high-RON octane booster. The ratio of fuel quantity on each injector is adapted to fit the RON requirement function of engine operating conditions.
2016-10-17
Technical Paper
2016-01-2292
Masaharu Kassai, Ken Torii, Taisuke Shiraishi, Toru Noda, Tor Kit Goh, Karsten Wilbrand, Shaun Wakefield, Adam Healy, David Doyle, Roger Cracknell, Masahiko Shibuya
Effect of lubricant oil and fuel properties on low speed pre-ignition (LSPI) occurrence in boosted S.I. engines was experimentally evaluated with multi-cylinder engine and de-correlated lubricant oil and fuel matrices. Furthermore, assuming droplets of lubricant oil and fuel mixture as ignition source, droplets spray and evaporated homogeneous mixture of lubricant oil and fuel were tested its auto-ignitability with combustion bomb and differential scanning calorimetry (DSC) to analyze fundamental ignition process. In addition to already reported dominant additives, effect of various detailed additives on LSPI occurrence was confirmed. Also, fuel volatility was found its effectiveness on LSPI occurrence. These results support and reconfirm the validity of the LSPI mechanism hypothesis that we are focusing on: droplets of lubricant oil and fuel mixture, caused by adhesion of fuel spray on liner wall, will fly and pre-ignite before spark ignition.
2016-10-17
Technical Paper
2016-01-2278
Ashutosh Gupta, Huifang Shao, Joseph Remias, Joseph Roos, Yinhui Wang, Yan Long, Zhi Wang, Shi-Jin Shuai
Superknock is an undesirable combustion phenomenon that limits the fuel economy, drivability, emissions and durability performance of modern turbocharged engines. Numerous researchers have previously reported that the frequency of super knock is sensitive to engine oil and fuel composition in controlled laboratory and engine-based studies. Several studies indicate that droplets of oil and residual fuel ejected from the piston crevice could play a role. Recent studies by Tsinghua University and Afton Chemical Corporation have demonstrated that controlled injection of oil-fuel droplets into the combustion chamber can induce pre-ignition and superknock. Afton and Tsinghua recently developed a 3D CFD engine simulation which was able to realistically model all of the elementary processes involved in droplet induced pre-ignition. The model was able to successfully simulate droplet induced pre-ignition at conditions where the phenomenon has been experimentally observed.
2016-10-17
Technical Paper
2016-01-2257
Hua LI, Liang Yu, Linqi Ouyang, Shuzhou Sun
The ignition delay time of toluene reference fuels composed of isooctane, n-heptane and toluene was studied in a shock tube under the conditions of medium to high temperature ranges, different pressures (10-20 bar), and various equivalence ratios (0.5,1.0,1.5 and 2) by reflected waves.Three different ternary blends, TRF2 (42.8% isooctane/13.7% n-heptane/43.5% toluene), TRF3 (65% isooctane/10% n-heptane/25% toluene) and TRF4 (87.2% isooctane/6.3% n-heptane/6.5% toluene), with the same Research Octane Number of 95 (RON=95) were constructed. The experimental results showed that there was an obvious negative correlation between the ignition delay time of the toluene reference fuels and the pressure, temperature and equivalence ratio; and, a minimal discrepancy of TRF2, TRF3, and TRF4 was measured at pressures of 10 and 20 bar in a stoichiometric ratio. Based on Curran’s detailed kinetic model for PRF (primary reference fuel) (Combust.
2016-10-17
Technical Paper
2016-01-2294
Hwasup Song, Han Ho Song
Livengood-Wu integration model is acknowledged as a relatively simple but fairly accurate autoignition prediction method which has been widely recognized as a methodology predicting knock occurrence of a spark-ignition (SI) engine over years. Fundamental idea of the model is that the chemical reactivity of fuel under a certain thermodynamic test condition can be represented by inverse of the acquired ignition delay. However, recent studies show that the predictability of the model seems to deteriorate if the tested fuel exhibits negative temperature coefficient (NTC) behavior which is primarily caused by two-stage ignition characteristics. It is convincing that the cool flame exothermicity during the first ignition stage is a major cause that limits the prediction capability of the integration model, therefore a new ignition delay concept based on cool flame elimination is introduced in order to minimize the thermal effect of the cool flame.
2016-10-17
Technical Paper
2016-01-2293
Michael Pamminger, James Sevik, Riccardo Scarcelli, Thomas Wallner, Steven Wooldridge, Brad Boyer
The compression ratio is a strong lever to increase the efficiency of an internal combustion engine. However, it is limited by the knock resistance of the fuel used. Natural gas shows a higher knock resistance compared to gasoline, which makes it very attractive for use in internal combustion engines. The current paper describes the knock behavior of gasoline fuels, and specific in-cylinder blend ratios with one of the gasoline fuels and natural gas. The engine used for these investigations is a single cylinder research engine for light duty application which is equipped with two separate fuel systems. Both fuels can be used simultaneously which allows for gasoline to be injected into the intake port and natural gas to be injected directly into the cylinder to overcome the power density loss usually connected with port fuel injection of natural gas.
2016-10-17
Technical Paper
2016-01-2234
Ahmed F. Khan, Alexey Burluka, Jens Neumeister, Dave OudeNijeweme, Paul Freeland, John Mitcalf
A holistic modelling approach has been employed to predict combustion, cyclic variability and knock propensity of a turbocharged downsized SI engine fuelled with gasoline. A quasi-dimensional, thermodynamic combustion modelling approach has been coupled with chemical kinetics modelling of autoignition using reduced mechanisms for realistic gasoline surrogates. The quasi-dimensional approach allows a fast and appreciably accurate prediction of the effects of operating conditions on the burn-rate and makes it possible to evaluate engine performance. It has also provided an insight into the nature of the turbulent flame as the boost pressure and speed is varied. In order to assess the sensitivity of the end-gas chemical kinetics to cyclic variability, the in-cylinder turbulence and charge composition were perturbed according to a Gaussian distribution.
2016-10-17
Technical Paper
2016-01-2209
Uisung Lee, Jeongwoo Han, Michael Wang, Jacob Ward, Elliot Hicks, Dan Goodwin, Rebecca Boudreaux, Per Hanarp, Henrik Salsing, Parthav Desai, Emmanuel Varenne, Patrik Klintbom, Werner Willems, Sandra L. Winkler, Heiko Maas, Robert De Kleine, John Hansen, Tine Shim, Erik Furusjö
Dimethyl Ether (DME) is an alternative to diesel for use in specially designed compression ignition diesel engines. A key advantage of using DME is the potential for reaching ultralow levels of regulated emissions using simple exhaust aftertreatment technologies and the absence of soot. DME can be produced from natural gas or from renewable feedstocks such as landfill gas or renewable natural gas from waste streams. This study investigates the well-to-wheels (WTW) energy use and emissions of several DME pathways as compared with those of petroleum gasoline and diesel using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model that is developed at Argonne National Laboratory. The DME pathways include small scale DME production from landfill gas, manure-based biogas and methanol from fossil natural gas (NG), and large scale DME production directly from fossil NG.
2016-10-17
Technical Paper
2016-01-2244
Ulrich Spicher, Max Magar, Jens Hadler
Today, most gasoline direct injection engines (DISI) are developed as downsizing concepts featuring homogeneous mixtures and boosting (turbocharging). These engines exhibit increased power output, improved torque behavior as well as lower fuel consumption in typical test cycles compared to conventional gasoline engines. Future emission legislations will focus on real driving conditions that generally result in increased fuel consumption and exhaust emissions compared to the present statutory testing conditions. Thus a considerable optimization of the combustion process has to be achieved in order to meet future emission standards under real driving conditions. In order to enable considerable improvements in engine efficiency and emissions mixture stratification in combination with boosting has to be implemented for part load conditions. However in high to full load operation a stoichiometric homogeneous mixture is still required.
2016-10-17
Technical Paper
2016-01-2167
Kohtaro Hashimoto, Tomohide Kudo, Takuya Sato, Ichiro Takase, Takamasa Suzuki, Tatsuya Nakano
In order to develop the on-board gasoline reforming technology that provides higher octane number fuel on demand, octane number enhancement of gasoline surrogate by aerobic oxidation using nitroxy imide catalyst was investigated. At first, octane number of the oxidative species from alkane and aromatic compound were estimated using fuel ignition analyzer. As a result, not only alcohols but also ketones and aldehydes have higher octane number than the original alkanes and aromatic compound. Then, gasoline surrogate was oxidized aerobically with nitroxy imide catalyst and cobalt catalyst under lower than 100degree C condition. As a result, fuel molecules were oxidized to produce alcohols, ketones, aldehydes, and ‎carboxylic acids. Nitroxy imide catalyst that has higher solubility in gasoline surrogate has higher oxidation ability. Furthermore, the estimated octane number of the oxidized gasoline surrogate improves 16 RON.
2016-10-17
Technical Paper
2016-01-2291
Yongsheng He, Zhimin Liu, Ian Stahl, Guiqiang Zhang, Youneng Zheng
Stochastic pre-ignition (SPI) has been commonly observed on turbocharged gasoline engines at low-speed high-load conditions, which causes extremely high peak cylinder pressure that can damage an engine immediately or degrade the engine life. The SPI was found to be strongly related to the characteristics of fuel and/or lubricants used by the engine. This study experimentally evaluated the frequency and severity of SPI on a 2.0L 4-cylinder turbocharged spark-ignition direct-injection (SIDI) engine with China market premium fuel and China blended US Tier-2 fuel samples. Key fuel properties were identified and correlated to SPI events. Two different types of engine oils were also tested and their impact on SPI were compared.
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
2016-01-0748
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
2016-01-0842
Joshua Lacey, Farzad Poursadegh, Michael Brear, Phred Petersen, Charles Lakey, Steve Ryan, Brendan Butcher
Abstract The focus of internal combustion (IC) engine research is the improvement of fuel economy and the reduction of the tailpipe emissions of CO2 and other regulated pollutants. Promising solutions to this challenge include the use of both direct-injection (DI) and alternative fuels such as liquefied petroleum gas (LPG). This study uses Mie-scattering and schlieren imaging to resolve the liquid and vapor phases of propane and iso-octane, which serve as surrogates for LPG and gasoline respectively. These fuels are imaged in a constant volume chamber at conditions that are relevant to both naturally aspirated and boosted, gasoline direct injection (GDI) engines. It is observed that propane and iso-octane have different spray behaviors across these conditions. Iso-octane is subject to conventional spray breakup and evaporation in nearly all cases, while propane is heavily flash-boiling throughout the GDI operating map.
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
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
Technical Paper
2016-01-0816
Yintong Liu, Liguang Li, Haifeng Lu, Jun Deng, Zongjie Hu
Abstract Due to much higher pressure and pressure rising rate, knocking is always of potential hazards causing damages in the engine and high NOX emissions. Therefore, the researchers have focused on knocking diagnosis and control for many years. However, there is still lack of fast response sensor detecting in-cycle knocking. Until now, the feedback control based on knocking sensor normally adjusts the injection and ignition parameters of the following cycles after knocking appears. Thus in-cycle knocking feedback control which requires a predictive combustion signal is still hard to see. Ion current signal is feasible for real-time in-cylinder combustion detection, and can be employed for misfiring and knocking detection. Based on incylinder pressure and ion current signals, the in-cycle knocking feedback control is investigated in this research.
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.
2016-04-05
Journal Article
2016-01-0889
Chuang Fan, Sunyu Tong, Xiaohong Xu, Jing Li, Xiao Yu He, Jun Deng, Liguang Li
Downsizing gasoline direct injection engine with turbo boost technology is the main trend for gasoline engine. However, with engine downsizing and ever increasing of power output, a new abnormal phenomenon, known as pre-ignition or super knock, occurs in turbocharged engines. Pre-ignition will cause very high in-cylinder pressure and high oscillations. In some circumstances, one cycle of severe pre-ignition may damage the piston or spark plug, which has a severe influence on engine performance and service life. So pre-ignition has raised lots of attention in both industry and academic society. More and more studies reveal that the auto-ignition of lubricants is the potential source for pre-ignition. The auto-ignition characteristics of different lubricants are studied. This paper focuses on the ignition delay of different lubricants in Controllable Active Thermo-Atmosphere (CATA) combustion system.
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
Technical Paper
2016-01-0830
Takashi Nomura, Shigehiko Sato, Jumpei Takahashi, Masayuki Ichiyanagi
Port fuel injection (PFI) injector and direct fuel injection (DI) injector clogging from deposits caused by poor fuel quality, is a concern in emerging countries. Then DI injector deposits are sometimes cleaned by injector cleaners in such situation. However deposit cleaners for PFI injectors have not been developed, because of the lack of research of PFI injector deposits. Through chemical analysis, this study showed them to be water-soluble deposits. Subsequently success was achieved in developing a new gasoline injector cleaner applicable to injector deposits in both types of injectors, through optimization of a surface active agent.
2016-04-05
Technical Paper
2016-01-0831
Young Suk Jo, Leslie Bromberg, John Heywood
Abstract High octane fuel (e.g., E85) effectively suppresses knock, but the octane ratings of such fuels are much above what is required under normal driving conditions. It is important, therefore, to understand the octane requirement of the engine itself over its full range of operation and apply that knowledge to practical driving cycles to understand fuel octane utilization, especially of a turbocharged engine. By carefully defining knock limits, the octane requirement of a 2-liter turbocharged spark ignition engine was experimentally quantified over a wide range of loads and speeds using PRF blends and gasoline-ethanol blends. Utilizing this knowledge and engine-in-vehicle simulations, the octane requirements of various driving cycles were calculated for a passenger car and a medium duty truck model.
2016-04-05
Technical Paper
2016-01-0903
Ram Vijayagopal, Kevin Gallagher, Daeheung Lee, Aymeric Rousseau
Abstract The energy density and power density comparison of conventional fuels and batteries is often mentioned as an advantage of conventional vehicles over electric vehicles. Such an analysis often shows that the batteries are at least an order of magnitude behind fuels like gasoline. However this incomplete analysis ignores the impact of powertrain efficiency and mass of the powertrain itself. When we compare the potential of battery electric vehicles (BEVs) as an alternative for conventional vehicles, it is important to include the energy in the fuel and their storage as well as the eventual conversion to mechanical energy. For instance, useful work expected out of a conventional vehicle as well as a BEV is the same (to drive 300 miles with a payload of about 300 lb). However, the test weight of a Conventional vehicle and BEV will differ on the basis of what is needed to convert their respective stored energy to mechanical energy.
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