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Viewing 151 to 180 of 23252
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
2016-01-1283
Akshay Kumar, Ashraya Gupta, Ketan Kamra
Abstract Worldwide, research is going on numerous types of engines that practice green and alternative energy such as natural gas engines, hydrogen engines, and electric engines. One of the possible alternatives is the air powered car. Air is abundantly available and can be effortlessly compressed to higher pressure at a very low cost. After the successful development of Compressed Air Engines, engineers shifted their focus in making this technology cost effective and feasible. This led to advancement in the field of pneumatics that is advanced Compressed Air Engine Kit (used for conversion of a small-two stroke SI engine to Compressed Air Engine) where its frugality and compatibility is kept at high priority. This research is in continuation with our previous project of development of an advanced Compressed Air Engine kit and optimisation of injection angle and injector nozzle area for maximum performance.
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
2016-01-1287
Kazutaka Kimura, Yuki Kudo, Akinori Sato
Abstract In recent years, automakers have been developing various types of environmentally friendly vehicles such as hybrid (HV), plug-in hybrid (PHV), electric (EV), and fuel cell (FCV) vehicles to help reduce greenhouse gas (GHG) emissions. However, there are few commercial solar vehicles on the market. One of the reasons why automakers have not focused attention on this area is because the benefits of installing solar modules on vehicles under real conditions are unclear. There are two difficulties in measuring the benefits of installing solar modules on vehicles: (1) vehicles travel under various conditions of sunlight exposure and (2) sunlight exposure conditions differ in each region. To address these problems, an analysis was performed based on an internet survey of 5,000 people and publically available meteorological data from 48 observation stations in Japan.
2016-04-05
Technical Paper
2016-01-1286
Takuya Hara, Takahiro Shiga, Kazutaka Kimura, Akinori Sato
Abstract Introducing effective technologies to reduce carbon emissions in the transport sector is a critical issue for automotive manufacturers to contribute to sustainable development. Unlike the plug-in electric vehicles (PEVs), whose effectiveness is dependent on the carbon intensity of grid electricity, the solar hybrid vehicle (SHV) can be an alternative electric vehicle because of its off-grid, zero-emission electric technology. Its usability is also advantageous because it does not require manual charging by the users. This study aims at evaluating the economic, environmental, and usability benefits of SHV by comparing it with other types of vehicles including PEVs. By setting cost and energy efficiency on the basis of the assumed technology level in 2030, annual cost and annual CO2 emissions of each vehicle are calculated using the daily mileage pattern obtained from a user survey of 5,000 people in Japan and the daily radiation data for each corresponding user.
2016-04-05
Technical Paper
2016-01-1285
Xiang Cheng, Han Hao, Zongwei Liu, Fuquan Zhao
Abstract Compared with conventional vehicles, electric vehicles (EVs) offer the benefits of replacing petroleum consumption and reducing air pollutions. However, there have been controversies over greenhouse gas (GHG) emissions of EVs from the life-cycle perspective in China’s coal-dominated power generation context. Besides, it is in doubt whether the cost-effectiveness of EVs in China exceeds other fuel-efficient vehicles considering the high prices. In this study, we compared the life-cycle GHG emissions of existing vehicle models in the market. Afterwards, a cost model is established to compare the total costs of vehicles. Finally, the cost-effectiveness of different vehicle types are compared. It is concluded that the GHG emission intensity of EVs is lower than reference and hybrid vehicles currently and is expected to decrease with the improvement of the power grid.
2016-04-05
Technical Paper
2016-01-1284
Andrew Burnham, Hao Cai, Michael Wang
Abstract A heavy-duty vehicle (HDV) module of the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREETTM) model has been developed at Argonne National Laboratory. The fuel-cycle GREET model has been published extensively and contains data on fuel-cycles and vehicle operation of light-duty vehicles. The addition of the HDV module to the GREET model allows for well-to-wheel (WTW) analyses of heavy-duty advanced technology and alternative fuel vehicles (AFVs), which has been lacking in the literature. WTW analyses of HDVs becomes increasingly important to understand the fuel consumption and greenhouse gas (GHG) emissions impacts of newly enacted and future HDV regulations from the Environmental Protection Agency and the Department of Transportation’s National Highway Traffic Safety Administration.
2016-04-05
Technical Paper
2016-01-1292
Manish Dixit, V Sundaram, Sathish Kumar S
Abstract Noise pollution is a major concern for global automotive industries which propels engineers to evolve new methods to meet passenger comfort and regulatory requirements. The main purpose of an exhaust system in an automotive vehicle is to allow the passage of non-hazardous gases to the atmosphere and reduce the noise generated due to the engine pulsations. The objective of this paper is to propose a Design for Six Sigma (DFSS) approach followed to optimize the muffler for better acoustic performance without compromising on back pressure. Conventionally, muffler design has been an iterative process. It involves repetitive testing to arrive at an optimum design. Muffler has to be designed for better acoustics performance and reduced back pressure which complicates the design process even more.
2016-04-05
Technical Paper
2016-01-1291
Greig Latham
Abstract Applying the Economic Input-Output Life Cycle Assessment (EIOLCA) method to the question of fielding newly manufactured or remanufactured vehicles provides an illuminating view of the economic and environmental advantages of remanufacturing. Sustained accomplishments of policy and engineering have reduced vehicle emissions such that current work has reached the point of diminishing returns. The macroeconomic, global, unprecedented, debt-supercycle-combined with increasing costs of natural resource extraction and vehicle production-demands improved asset and resource utilization. Expanding and exploiting the entire vehicle life cycle is a profitable and sustainable extension of work to date; such extension calls for remanufacturing to move from vehicle components to the entire vehicle. Stretching service lifetimes delay traditional end-of-life recovery practices while radically challenging the status quo.
2016-04-05
Technical Paper
2016-01-1290
J. Groenewald, James Marco, Nicholas Higgins, Anup Barai
Abstract While a number of publications have addressed the high-level requirements of remanufacturing to ensure its commercial and environmental sustainability, considerably less attention has been given to the technical data and associated test strategies needed for any evidence-based decision as to whether a vehicle energy storage system should be remanufactured - extending its in-vehicle life, redeployed for second-life (such as domestic or grid storage) or decommissioned for recycling. The aim of this paper is to critically review the strategic requirements for data at the different stages of the battery value-chain that is pertinent to an Electric Vehicle (EV) battery remanufacturing strategy. Discussed within the paper is the derivation of a feasible remanufacturing test strategy for the vehicle battery system.
2016-04-05
Technical Paper
2016-01-0826
Arumugam Sakunthalai Ramadhas, Hongming Xu
Abstract Ambient temperature has significant impact on engine start ability and cold start emissions from diesel engines. These cold start emissions are accounted for substantial amount of the overall regulatory driving cycle emissions like NEDC or FTP. It is likely to implement the low temperature emissions tests for diesel vehicles, which is currently applicable only for gasoline vehicles. This paper investigates the potential of the intake heating strategy on reducing the driving cycle emissions from the latest generation of turbocharged common rail direct injection diesel engines at low ambient temperature conditions. For this investigation an air heater was installed upstream of the intake manifold and New European Driving Cycle (NEDC) tests were conducted at -7°C ambient temperature conditions for the different intake air temperatures. Intake air heating reduced the cranking time and improved the fuel economy at low ambient temperatures.
2016-04-05
Technical Paper
2016-01-0825
William Fedor, Joseph Kazour, James Haller, Kenneth Dauer, Daniel Kabasin
Abstract LEV-3 regulation changes require 100% SULEV30 fleet average by 2025. While present applications meeting SULEV30 are predominately small displacement 4-cylinder engines, LEV-3 standards will require larger displacement engines to also meet SULEV30. One concept previously investigated to reduce the cold start engine-out HC emissions was to heat the fuel injected during the cold start and initial engine idle period. Improved atomization and increased vaporization of heated fuel decreased wall wetting and unburned fuel. This resulted in more fuel available to take part in combustion, thus reducing the required injected fuel mass and HC emissions. Single cylinder engine testing with experimental heated Gasoline Direct Injection (GDi) injectors was conducted at 40°C engine coolant and oil temperature conditions. The operating mode simulated cold start idle operating conditions, with split injection for improved Catalyst Light-Off (CATLO) times.
2016-04-05
Technical Paper
2016-01-0823
Jason Miwa, Darius Mehta, Chad Koci
Abstract Increasingly stringent emissions regulations require that modern diesel aftertreatment systems must warm up and begin controlling emissions shortly after startup. While several new aftertreatment technologies have been introduced that focus on lowering the aftertreatment activation temperature, the engine system still needs to provide thermal energy to the exhaust for cold start. A study was conducted to evaluate several engine technologies that focus on improving the thermal energy that the engine system provides to the aftertreatment system while minimizing the impact on fuel economy and emissions. Studies were conducted on a modern common rail 3L diesel engine with a custom dual loop EGR system. The engine was calibrated for low engine-out NOx using various combustion strategies depending on the speed/load operating condition.
2016-04-05
Technical Paper
2016-01-0838
Yinhui Wang, Rong Zheng, Shi-Jin Shuai, Yanhong Qin, Jianfei Peng, He Niu, Mengren Li, Yusheng Wu, Sihua Lu, Min Hu
An experimental study of particulate matter and volatile organic compounds (VOCs) emissions was conducted on a direct injection gasoline (DIG) engine and a port fuel injection (PFI) engine which both were produced by Chinese original equipment manufacturers (OEMs) to investigate the impact of fuel properties from Chinese market on particulate and VOCs emissions from modern gasoline vehicles. The study in this paper is just the first step of the work which is to investigate the impact of gasoline fuel properties and light duty vehicle technologies on the primary and secondary emissions, which are the sources of particulate matter 2.5 (PM2.5) in the atmosphere in China. It is expected through the whole work to provide some suggestions and guidelines on how to improve air quality and mediate severe haze pollution in China through fuel quality control and vehicle technology advances.
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
2016-01-0810
Massimo Cardone, Ezio Mancaruso, Renato Marialto, Luigi Sequino, Bianca Maria Vaglieco
Abstract The interest of the vehicle producers in fulfillment emission legislations without adopting after treatment systems is driving to the use of non-conventional energy sources for modern engines. A previous test campaign dealing with the use of blends of diesel and propane in a CI engine has pointed out the potential of this non-conventional fuel for diesel engines. The soft adaptation of the common rail injection system and the potential benefits, in terms of engine performances and pollutant emissions, encourage the use of propane-diesel blends if an optimization of the injection strategies is performed. In this work, the performances of a propane-diesel mixture in a research diesel engine have been investigated. The injection strategies of Euro 5 calibration have been used as reference for the development of optimized strategies. The aim of the optimization process was to ensure the same engine power output and reduce the pollutant emissions.
2016-04-05
Technical Paper
2016-01-0807
Christopher W. J. Mabson, Ehsan Faghani, Pooyan Kheirkhah, Patrick Kirchen, Steven N. Rogak, Gordon McTaggart-Cowan
Abstract This paper examines the combustion and emissions produced using a prototype fuel injector nozzle for pilot-ignited direct-injection natural gas engines. In the new geometry, 7 individual equally-spaced gas injection holes were replaced by 7 pairs of closely-aligned holes (“paired-hole nozzle”). The paired-hole nozzle was intended to reduce particulate formation by increasing air entrainment due to jet interaction. Tests were performed on a single-cylinder research engine at different speeds and loads, and over a range of fuel injection and air handling conditions. Emissions were compared to those resulting from a reference injector with equally spaced holes (“single-hole nozzle”). Contrary to expectations, the CO and PM emissions were 3 to 10 times higher when using the paired-hole nozzles. Despite the large differences in emissions, the relative change in emissions in response to parametric changes was remarkably similar for single-hole and paired-hole nozzles.
2016-04-05
Technical Paper
2016-01-0822
Jongwon Chung, Namho Kim, Hoimyung Choi, Kyoungdoug Min
Abstract Due to the direct injection of fuel into a combustion chamber, particulate emission is a challenge in DISI engines. Specifically, a significant amount of particulate emission is produced under the cold start condition. In this research, the main interest was to investigate particulate emission characteristics under the catalyst heating condition because it is one of the significant particulate-emissionproducing stages under the cold start condition. A single-cylinder optically accessible engine was used to investigate the effect of injection strategies on particulate emission characteristics under the catalyst heating condition. The split injection strategy was applied during intake stroke with various injection pressures and injection timings. Using luminosity analysis of the soot radiation during combustion, the particulate formation characteristics of each injection strategy were studied.
2016-04-05
Technical Paper
2016-01-0646
Pablo Olmeda, Jaime Martin, Antonio Garcia, Diego Blanco, Alok Warey, Vicent Domenech
Abstract Regulated emissions and fuel consumption are the main constraints affecting internal combustion engine (ICE) design. Over the years, many techniques have been used with the aim of meeting these limitations. In particular, exhaust gas recirculation (EGR) has proved to be an invaluable solution to reduce NOx emissions in Diesel engines, becoming a widely used technique in production engines. However, its application has a direct effect on fuel consumption due to both the changes in the in-cylinder processes, affecting indicated efficiency, and also on the air management. An analysis, based on the engine Global Energy Balance, is presented to thoroughly assess the behavior of a HSDI Diesel engine under variable EGR conditions at different operating points. The tests have been carried out keeping constant the conditions at the IVC and the combustion centering.
2016-04-05
Technical Paper
2016-01-0659
Alok Warey, Venkatesh Gopalakrishnan, Michael Potter, Enrico Mattarelli, Carlo Alberto Rinaldini
Abstract Two-stroke diesel engines could be a promising solution for reducing carbon dioxide (CO2) emissions from light-duty vehicles. The main objective of this study was to assess the potential of two-stroke engines in achieving a substantial reduction in CO2 emissions compared to four-stroke diesel baselines. As part of this study 1-D models were developed for loop scavenged two-stroke and opposed piston two-stroke diesel engine concepts. Based on the engine models and an in-house vehicle model, projections were made for the CO2 emissions for a representative light-duty vehicle over the New European Driving Cycle and the Worldwide Harmonized Light Vehicles Test Procedure. The loop scavenged two-stroke engine had about 5-6% lower CO2 emissions over the two driving cycles compared to a state of the art four-stroke diesel engine, while the opposed piston diesel engine had about 13-15% potential benefit.
2016-04-05
Technical Paper
2016-01-0669
Shikhar Asthana, Shubham Bansal, Shubham Jaggi, Naveen Kumar
Abstract The Automobile industry is under great stress due to greenhouse gas emissions and health impacts of pollutants. The rapid decrease of fossil fuels has promoted the development of engine designs having higher fuel economy. At the same time, these designs keep the stringent emission standards in check without sacrificing brake power. Variable Compression Ratio (VCR) is one such measure. This work reviews the technological advancements in the design of a VCR engine. VCR engines can minimize possible risks of irregular combustion while optimizing Brake specific fuel consumption towards higher power and torque. An increase in fuel economy is seen for VCR naturally aspirated engines when coupled with downsizing. In addition to this, emissions of carbon dioxide decreases due to effective utilization of fuel at high loads. Since the first VCR design, there have been various modifications and improvements in VCR engine design.
2016-04-05
Technical Paper
2016-01-0631
Emilio Navarro-Peris, Estefanía Hervas-Blasco, José M. Corberan, Alex Rinaldi
Abstract The present concern in the reduction of CO2 emissions occasioned by heavy duty trucks is leading to a technological evolution, among others, in powertrain electrification. Towards this objective, the EU has funded the project GASTone targeting the development of a new powertrain concept based on the energy recovery from the exhaust gases and kinetic losses in order to make possible the electrification of the main auxiliaries. This new concept will follow a cascade approach in which the exhaust gases energy will be recovered by the integration of an advanced thermoelectric generator followed by a turbo-generator. This system will be combined with a smart kinetic energy recovery device which will recover the energy losses in the deceleration periods of the vehicle. The recovered energy will be used in the electrified auxiliaries.
2016-04-05
Technical Paper
2016-01-0733
Valentin Soloiu, Tyler Naes, Martin Muinos, Spencer Harp, Jose Moncada, Remi Gaubert, Gustavo Molina
Abstract This study investigates combustion and emissions of Jet-A in an indirect injection (IDI) compression ignition engine and a direct injection (DI) compression ignition engine at 4.5 bar IMEP and 2000 RPM. The Jet-A was blended with ULSD that resulted in 75%Jet-A and 25% ULSD#2 by mass. Both engines were instrumented with Kistler pressure sensors in the main chamber and the IDI engine had a second pressure sensor in the pre-chamber. Combustion properties and emissions from both engines using the 75% jet-A blend (75Jet-A) were compared to a baseline test of Ultra Low Sulfur Diesel #2 (ULSD). The ignition delay was shorter when running on 75Jet-A compared to ULSD in the DI engine. For ULSD, the ignition delay was 1.8 ms and it reduced to 1.7 ms when operating on 75Jet-A (difference of 6%). In the IDI engine the ignition delay for both fuels was 2.3 ms based off the gross heat release in the Pre-Chamber.
2016-04-05
Technical Paper
2016-01-0727
Cody William Squibb, Harold Schock, Ravi Vedula, Thomas Stuecken
Abstract In-cylinder visualization experiments were completed using an International VT275-based optical DI Diesel engine operating under high simulated exhaust gas recirculation combustion conditions. Experiments were run at four load conditions to examine variations in fuel spray, combustion, and soot production. Mass fraction burned analyses of pressure data were used to investigate the combustion processes of the various operating conditions. An infrared camera was used to visualize fuel spray events and exothermic combustion gases. A visible, high-speed camera was used to image natural luminosity produced by soot. The recorded images were post-processed to analyze the fuel spray, the projected exothermic areas produced by combustion, as well as soot production of different load conditions. Probability maps of combustion and fuel spray occurrence in the cylinder are presented for insight into the combustion processes of the different conditions.
2016-04-05
Technical Paper
2016-01-0726
Jonathan Martin, Chenxi Sun, Andre Boehman, Jacqueline O'Connor
Abstract This experimental study involves optimization of the scheduling of diesel post injections to reduce soot emissions from a light-duty diesel engine. Previous work has shown that certain post injection schedules can reduce engine-out soot emissions when compared to conventional injection schedules for the same engine load. The purpose of this study is to investigate the impact of post injection scheduling for a range of engine conditions on a light duty multicylinder turbodiesel engine (1.9L GM ZDTH). For each engine operating condition, a test grid was developed so that only two variables (post injection duration and the commanded dwell time between main injection and post injection) were varied, with all other conditions held constant, in order to isolate the effects of the post injection schedule. Results have identified two distinct regimes of post injection schedules that reduce soot emissions.
2016-04-05
Technical Paper
2016-01-0683
Kai Morganti, Abdullah Alzubail, Marwan Abdullah, Yoann Viollet, Robert Head, Junseok Chang, Gautam Kalghatgi
Abstract This paper is the second of a two part study which investigates the use of advanced combustion modes as a means of improving the efficiency and environmental impact of conventional light-duty vehicles. This second study focuses on drive cycle simulations and Life Cycle Assessment (LCA) for vehicles equipped with Octane-on-Demand combustion. Methanol is utilized as the high octane fuel, while three alternative petroleum-derived fuels with Research octane numbers (RONs) ranging from 61 to 90 are examined as candidates for the lower octane fuel. The experimental engine calibration maps developed in the previous study are first provided as inputs to a drive cycle simulation tool. This is used to quantify the total fuel consumption, octane requirement and tank-to-wheel CO2 emissions for a light-duty vehicle equipped with two alternative powertrain configurations.
2016-04-05
Technical Paper
2016-01-0676
Mohamed Shaaban Khalef, Alec Soba, John Korsgren
Abstract An experimental study of EGR and turbocharging concepts has been performed on an experimental 2.0-litre 4-cylinder turbocharged Euro6 light-duty diesel engine. The purpose of the study was to investigate the emissions and fuel consumption trade-off for different concept combinations. The impact of low-pressure and high-pressure EGR was studied in terms of engine-out emissions and fuel consumption. Moreover, the influence of single-stage and two-stage turbocharging was investigated in combination with the EGR systems, and how the engine efficiency could be further improved after engine calibration optimization. During low load engine operation where throttling may be required to achieve the desired low-pressure EGR rate, the difference in fuel consumption impact was studied for exhaust throttling and intake throttling, respectively. The cooling impact on high-pressure EGR was compared in terms of emissions and fuel consumption.
2016-04-05
Technical Paper
2016-01-0697
Francesco Catapano, Silvana Di Iorio, Ludovica Luise, Paolo Sementa, Bianca Maria Vaglieco
Abstract In this paper, the effect of the oxygen addition on engine performance and exhaust emissions was investigated. The experimental study was carried out in a small single-cylinder PFI SI four-stroke engine. The addition of the 5% vol and 10% vol of oxygen was performed in the intake duct. Typical urban driving operating conditions were investigated. The engine emissions were characterized by means of gaseous analyzers and a smokemeter. Particle size distribution function was measured in the size range from 5.6 to 560 nm by means of an Engine Exhaust Particle Sizer (EEPS). An improvement in terms of engine power output, without BSFC penalty, and HC emissions with oxygen addition was observed at all the investigated operating conditions. On the other hand, NOx and PM emissions increase.
2016-04-05
Technical Paper
2016-01-0698
Zheng Xu, Zhou Zhou, Tao Wu, Tong Li, Chuanhui Cheng, Haiting Yin
Abstract Engine downsizing has become a leading trend for fuel consumption reduction while maintaining the high specific power and torque output. Because of this, Turbo-charged Gasoline Direct Injection (TGDI) technology has been widely applied in passenger vehicles even though a number of technical challenges are presented during the engine development. This paper presents the investigation results of three key issues in the combustion development of a 2.0L TGDI engine at SAIC motor: fuel dilution, smoke emission and low speed stochastic pre-ignition(LSPI). The effect of the injection timing and injection strategy on fuel dilution and smoke emission, and LSPI are the focus of the experimental study.
2016-04-05
Technical Paper
2016-01-0691
Gurneesh S. Jatana, Brian C. Kaul, Robert Wagner
Abstract Spark-ignition (SI) engines can derive substantial efficiency gains from operation at high dilution levels, but sufficiently high-dilution operation increases the occurrence of misfires and partial burns, which induce higher levels of cyclic-variability in engine operation. This variability has been shown to have both stochastic and deterministic components, with residual fraction impacts on charge composition being the major source of the deterministic component through its non-linear effect on ignition and flame propagation characteristics. This deterministic coupling between cycles offers potential for next-cycle control approaches to allow operation near the edge of stability. This paper aims to understand the effect of spark strategies, specifically the use of a second spark (restrike) after the main spark, on the deterministic coupling between engine cycles by operating at high dilution levels using both excess air (i.e. lean combustion) and EGR.
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