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Potential for Emission Reduction and Fuel Economy with Micro & Mild HEV

AVL List GmbH-Franz Murr, Ernst Winklhofer, Michael Weissbaeck, Gerald Teuschl
  • Technical Paper
  • 2019-28-2504
Published 2019-11-21 by SAE International in United States
The development of modern combustion engines (spark ignition as well as compression ignition) for vehicles compliant with future oriented emission legislation (BS6, Euro VI, China 6) has introduced several technologies for improvement of both fuel efficiency as well as low emissions combustion strategies. Some of these technologies as there are high pressure multiple injection systems or sophisticated exhaust gas after treatment system imply substantial increase in test and calibration time as well as equipment cost.With the introduction of 48V systems for hybridization a cost- efficient enhancement and, partially, an even attractive alternative is now available. An overview will be given on current technologies as well as on implemented test procedures. The focus will be on solutions which have potential for the Indian market, i.e. solutions which can be implemented with moderate application effort for currently available compact and medium size cars. The possibilities of 48V technologies for fuel economy and emission reduction will be discussed. Simultaneously, tools for testing and calibration at power train testbed as well as for on-road application will be presented.Furthermore, it…
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Powertrain Calibration Techniques

AVL LIST GmbH-Ernst Winklhofer, Alois Hirsch, Harald Philipp, Michael Trifterer, Manuel Berglez
Published 2019-09-09 by SAE International in United States
Meeting the particle number (PN) emissions limits in vehicle test sequences needs specific attention on each power variation event occurring in the internal combustion engine (ICE).ICE power variations arise from engine start onwards along the entire test drive. In hybrid systems, there is one further source for transient ICE response: each power shift between E-motor and ICE introduces gas flow variations with subsequent temperature response in the ICE and in the engine aftertreatment system (EAS). This bears consequences for engine out emissions as well as for the EAS efficiency and even for the durability of a catalytic converter.As system calibration engineers must decide on numerous actuator parameters, their decisions, finally, are crucial for meeting legislative limits under the boundary conditions given by the hybrid vehicle’s drive environment.The paper reports on a methodology to measure and evaluate the ICE and EAS response to the vehicle drive requirements and the power shift dynamics between E-motor and ICE.Focus in particular is given to1particle emissions peaks at each engine start and torque variation with measurement of in-cylinder soot formation…
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An Investigation into the Effect of Fuel Injection System Improvements on the Injection and Combustion of DiMethyl Ether in a Diesel Cycle Engine

AVL LIST GmbH-Denis W. Gill, Herwig Ofner, Carsten Stoewe, Karl Wieser, Ernst Winklhofer
DENSO Corp.-Masaaki Kato, Takamasa Yokota
Published 2014-10-13 by SAE International in United States
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. CFD simulation was also used to assist in the interpretation of the 2D test results.Tests were then run on…
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Reducing Emissions and Improving Fuel Economy by Optimized Combustion of Alternative Fuels

AVL List GmbH-Franz Murr, Ernst Winklhofer, Hubert Friedl
Published 2011-10-06 by The Automotive Research Association of India in India
Alternative fuels, especially fuels based on biological matter, are gaining more and more attention. Not only as a pure substitute of oil but also in terms of a possibility for further reduction in emission and as an option to improve the global CO2 balance.For improving the engine performance (emissions, fuel consumption, torque and drivability) the adjustment of fuel injection, the fuel evaporation process and the combustion process itself is paramount. In order to exploit the full potential of alternative fuels excellent knowledge of the fuel properties, including the impact on ignition and flame propagation, is required. This needs suitable tools for analysis of the fuel injection and combustion process. These tools have to support the optimization of the combustion system and the dynamic engine calibration for lowest emissions and most efficient use of fuel.As the term “Alternative Fuels” covers a very wide area a brief overview on available fuel types will be made. Also, the main characteristics of the most promising alternative fuels as currently used for propelling mass production cars and in commercial engines…
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Cylinder- and Cycle Resolved Particle Formation Evaluation to Support GDI Engine Development for Euro 6 Targets

AVL LIST GmbH-Ernst Winklhofer, Alois Hirsch, Harald Philipp
AVL List GmbH-Matthias Neubauer
Published 2011-09-11 by SAE International in United States
Combustion of premixed stoichiometric charge is free of soot particle formation. Consequently, the development of direct injection (DI) spark ignition (SI) engines aims at providing premixed charge to avoid or minimize soot formation in order to meet particle emissions targets. Engine development methods not only need precise engine-out particle measurement instrumentation but also sensors and measurement techniques which enable identification of in-cylinder soot formation sources under all relevant engine test conditions. Such identification is made possible by recording flame radiation signals and with analysis of such signals for premixed and diffusion flame signatures. This paper presents measurement techniques and analysis methods under normal engine and vehicle test procedures to minimize sooting combustion modes in transient engine operation.
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Optimization of Fuel Injection by Measurement of Mixture

AVL LIST GMBH-Ernst Winklhofer
Imagineering-Yuji Ikeda, Atsushi Nishiyama, Akira Takeuchi
  • Technical Paper
  • 2006-08-0126
Published 2006-05-01 by Society of Automotive Engineers of Japan in Japan
In this study, we demonstrated the usefulness of our micro-Cassegrain sensor in a single-cylinder engine. The local air excess ratio (Lambda: λ) was measured successfully by measuring the intensity ratios of three radicals, OH*, CH* and C2*, at close to the cylinder wall. The sensor had the same dimensions as an M5-type pressure transducer. The local λ and its cyclic variations were investigated in different injection mode. We found that the local l fluctuated with time, and showed that there was a large range of indicated mean effective pressure (IMEP), which would not be known from pressure data alone.
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3D-CFD and Optical Analysis of Flame Propagation and Knock Onset for Full Load SI Engine Combustion Optimization

AVL Japan-Mihoko Fukumoto
AVL List GmbH-Ernst Winklhofer, Reinhard Tatschl
  • Technical Paper
  • 2005-08-0097
Published 2005-05-18 by Society of Automotive Engineers of Japan in Japan
The development of SI engines under full load operating conditions more and more relies on CFD modelling and on experimental visualization of flame propagation and knock onset locations. In this context CFD and optical measurement techniques are complementary tools which provide a comprehensive space and time resolved insight into the relevant in-cylinder processes. The current status of CFD modelling and optical diagnostics for the study of flame propagation and the pre-reactions in the end-gas of SI engines are discussed in the article. Based on selected examples the different possibilities of analysis and assessment of the processes are discussed with regards to the actual development tasks.
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Performance Development on Prototype Single-Cylinder Engine: Systematic Combustion System Improvements for Optimum Engine Performance

AVL List GMBH-Ernst Winklhofer, Christian Spanner
Yamaha Marine CO..LTD.-Yoshibumi Iwata
Published 2004-09-27 by SAE International in United States
In recent years, many four-stroke outboard motors have been developed according to the market demand. But four-stroke outboard motor tends to be heavier and larger than conventional two-stroke one due to its more complex mechanism. The outboard motor is required to be light and compact not to disturb the utility of the boat. In addition, boat load requires higher torque at mid engine speed. In such situation, knocking is one of the obstacles against power density. We tried to improve combustion for high power density on a prototype single cylinder engine using up-to-date analyzing and development technology.
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Combustion Quality Assessment for New-Generation Gasoline Engines

AVL Japan-Hidetaka Nohira
AVL List GmbH-Ernst Winklhofer, Christian Beidl, Alois Hirsch, Walter F. Piock
  • Technical Paper
  • 2004-08-0086
Published 2004-05-19 by Society of Automotive Engineers of Japan in Japan
Actuators and components for modern gasoline engine combustion systems aim at exploiting best airflow and mixture conditions for optimizing each individual combustion cycle. Individual cycle combustion events are assessed via their flame signatures. Flame analysis in multicylinder production engines has become possible with the introduction of fiber optic inspection techniques. The refinement of measurement and data evaluation procedures has set the basis for the simplification of fiber optic measurement systems. Applications are optimized for assessment of idle and part load flame stability, of sooting diffusion flames versus clean premixed flames and of self-ignition centers. System standardization has allowed its integration as modular component in development and calibration test beds.
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Micro-optic sensor techniques for flame diagnostics

AVL List GmbH-Ernst Winklhofer, Christian Beidl, Harald Philipp, Walter F. Piock
  • Technical Paper
  • 2001-08-0030
Published 2001-05-23 by Society of Automotive Engineers of Japan in Japan
Optical sensor elements and sensing techniques for the observation of flame propagation and local self-ignition centers in SI engine combustion systems are presented. The micro-optic elements comprising small lenses together with optical fibers are implanted in engine components such as cylinder head gaskets or spark plugs. This allows application of the sensors or sensor arrangements in standard, multicylinder engines, without compromising engine operating conditions.The paper demonstrates multichannel sensor arrangements, their application in the study of flame propagation, and, together with indicating and imaging equipment, the integration of these diagnostic techniques in the workflow of SI combustion system development.