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Technical Paper
2014-10-13
Jay Anderson, Scott Miers, Thomas Wallner, Kevin Stutenberg, Henning Lohse-Busch, Michael Duoba
In recent years, increasing difficulty of crude oil production combined with rising oil prices and the popularization of green motoring have fostered greater research interest in alternative combustion fuels. Compressed Natural Gas (CNG) is a fuel that provides beneficial combustion properties, low tailpipe emissions and benefits from significant domestic production resources in the United States. Mainly because of these factors, CNG has begun see utilization in passenger vehicles. This work seeks to provide a practical evaluation of CNG as compared to gasoline as a fuel for use in passenger vehicle engines. To this end, two similar compact sedans were selected. The first is equipped with a gasoline combustion engine, while the second is powered by a modified version of this engine fueled with CNG. Both vehicles are factory configurations available for purchase. The vehicles were subjected to a number of chassis dynamometer tests including the UDDS, HWFET and US06 driving schedules as well as selected steady state testing.
Technical Paper
2014-04-01
Mohammad Reza Amini, Mahdi Shahbakhti, Ali Ghaffari
High hydrocarbon (HC) emission during a cold start still remains one of the major emission control challenges for spark ignition (SI) engines in spite of about three decades of research in this area. This paper proposes a cold start HC emission control strategy based on a reduced order modeling technique. A novel singular perturbation approximation (SPA) technique, based on the balanced realization principle, is developed for a nonlinear experimentally validated cold start emission model. The SPA reduced model is then utilized in the design of a model-based sliding mode controller (SMC). The controller targets to reduce cumulative tailpipe HC emission using a combination of fuel injection, spark timing, and air throttle / idle speed controls. The results from the designed multi-input multi-output (MIMO) reduced order SMC are compared with those from a full order SMC. The results show the reduced SMC outperforms the full order SMC by reducing both engine-out and tailpipe HC emission. This improved performance is caused by setting an optimum priority among the control inputs through the incorporation of SPA that evaluates the significance of the control variables/states on HC emission.
Technical Paper
2014-04-01
Wei Luo, Bo Chen, Jeffrey Naber, Chris Glugla
Abstract The ability to operate a spark-ignition (SI) engine near the knock limit provides a net reduction of engine fuel consumption. This work presents a real-time knock control system based on stochastic knock detection (SKD) algorithm. The real-time stochastic knock control (SKC) system is developed in MATLAB Simulink, and the SKC software is integrated with the production engine control strategy through ATI's No-Hooks. The SKC system collects the stochastic knock information and estimates the knock level based on the distribution of knock intensities fitting to a log-normal (LN) distribution. A desired knock level reference table is created under various engine speeds and loads, which allows the SKC to adapt to changing engine operating conditions. In SKC system, knock factor (KF) is an indicator of the knock intensity level. The KF is estimated by a weighted discrete FIR filter in real-time. Both offline simulation and engine dynamometer test results show that stochastic knock control with fixed length of finite impulse response (FIR) filter has slow and excessive retard issue when a significant knock event happens.
Technical Paper
2014-04-01
Jay Anderson, Eric Rask, Henning Lohse-Busch, Scott Miers
Vehicle operation during cold-start powertrain conditions can have a significant impact on drivability, fuel economy and tailpipe emissions in modern passenger vehicles. As efforts continue to maximize fuel economy in passenger vehicles, considerable engineering resources are being spent in order to reduce the consumption penalties incurred shortly after engine start and during powertrain warmup while maintaining suitably low levels of tailpipe emissions. Engine downsizing, advanced transmissions and hybrid-electric architecture can each have an appreciable effect on cold-start strategy and its impact on fuel economy. This work seeks to explore the cold-start strategy of several passenger vehicles with different powertrain architectures and to understand the resulting fuel economy impact relative to warm powertrain operation. To this end, four vehicles were chosen with different powertrain architectures. These include a modern conventional vehicle with a 6-speed automatic transmission equipped with a torque converter, a downsized and turbocharged GDI vehicle with a 7-speed dual-clutch transmission, a modern turbo-diesel with a 6-speed dual-clutch transmission, and a gasoline-electric hybrid with a power split transmission.
Technical Paper
2014-04-01
Thomas Wallner, Andrew Ickes, Jeff Wasil, James Sevik, Scott Miers
Abstract This study evaluates iso-butanol as a pathway to introduce higher levels of alternative fuels for recreational marine engine applications compared to ethanol. Butanol, a 4-carbon alcohol, has an energy density closer to gasoline than ethanol. Isobutanol at 16 vol% blend level in gasoline (iB16) exhibits energy content as well as oxygen content identical to E10. Tests with these two blends, as well as indolene as a reference fuel, were conducted on a Mercury 90 HP, 4-stroke outboard engine featuring computer controlled sequential multi-port Electronic Fuel Injection (EFI). The test matrix included full load curves as well as the 5-mode steady-state marine engine test cycle. Analysis of the full load tests suggests that equal full load performance is achieved across the engine speed band regardless of fuel at a 15-20°C increase in exhaust gas temperatures for the alcohol blends compared to indolene. This increase as well as the observed 2.5-3% point improvement in brake thermal efficiency of both alcohol blends compared to the reference fuel are caused by changes in air/fuel ratio; an effect ultimately attributable to the open loop engine control strategy.
Technical Paper
2013-09-30
Scott Huang, Jiann-Yang Hwang, Robert Page, Xiaobin Song, Jim Wagnitz, Nannon Huang, Gerald Schaefer, Matt Schaefer
Aluminum based brake rotors have been a priority research topic in the DOE 1999 Aluminum Industry Roadmap for the Automobile Market. After fourteen years, no satisfactory technology has been developed to solve the problem of aluminum's low working temperatures except the steel clad aluminum (SCA) brake technology. This technology research started at Michigan Technological University (MTU) in 2001 and has matured recently for commercial productions. The SCA brake rotor has a solid body and replaces the traditional convective cooling of a vented rotor with conductive cooling to a connected aluminum wheel. Much lower temperatures result with the aluminum wheel acting as a great heat sink/radiator. The steel cladding further increases the capability of the SCA rotor to withstand higher surface temperatures. During the road tests of SCA rotors on three cars, significant gas mileage improvement was found; primarily attributed to the unique capability of the SCA rotor on pad drag reduction.
Technical Paper
2013-04-08
Yang Li, Pushkar Agashe, Zicheng Ge, Bo Chen
Energy management is one of the key challenges for the development of Hybrid Electric Vehicle (HEV) due to its complex powertrain structure. Hardware-In-the-Loop (HIL) simulation provides an open software architecture which enables rapid prototyping HEV energy management system. This paper presents the investigation of the energy management system for a single shaft parallel hybrid electric vehicle using dSPACE eDrive HIL system. The parallel hybrid electric vehicle, energy management system, and low-level Electronic Control Unit (ECU) were modeled using dSPACE Automotive Simulation Models and dSPACE blocksets. Vehicle energy management is achieved by a vehicle-level controller called hybrid ECU, which controls vehicle operation mode and torque distribution among Internal Combustion Engine (ICE) and electric motor. The individual powertrain components such as ICE, electric motor, and transmission are controlled by low-level ECUs. To examine the performance of hybrid ECU and low-level ECUs, vehicle mode control, speed tracking, energy distribution, regenerative braking, and engine operating region were investigated in the HIL environment with a hardware electric motor controller consisting of dSPACE MicroAutoBox II and the AC Motor Control Solution.
Technical Paper
2013-04-08
Zhengshu Zhu
Battery management system (BMS) plays a key role in the power management of hybrid electric vehicles (HEV). It measures the state of charge (SOC), state of health (SOH) of the battery, protects the battery package and extends cells' life cycles. For HEV applications, lithium-ion battery is usually selected as electric power source due to its high specific energy, high energy density, and long life cycle. However, the non-linear characteristic of a Li-ion battery, complicated electro-chemical model, and environmental factors, raises the difficulties in the real-time estimation of the SOC for a Li-ion battery. To address this challenge, a BMS for HEVs is modeled with MATLAB/Simulink. In addition, a regenerative braking control strategy is proposed to determine the magnitude of the regenerative torque based on the battery SOC. The motor-generator system is optimized and modeled with regard to the operating time and power contribution of the e-motor during acceleration and the regeneration behavior of the generator during braking for maintaining the battery SOC within a proper range to achieve the longest battery life cycle and stable performance.
Technical Paper
2013-04-08
Jaclyn Johnson, Hai-Wen Ge, Jeffrey Naber, Seong-Young Lee, Eric Kurtz, Nan Robarge
Diesel combustion and emissions formation is spray and mixing controlled and understanding spray parameters is key to determining the impact of fuel injector operation and nozzle design on combustion and emissions. In this study, both spray visualization and computational fluid dynamics (CFD) modeling were undertaken to investigate key mechanisms for liquid length fluctuations. For the experimental portion of this study a common rail piezoelectric injector was tested in an optically accessible constant volume combustion vessel. Liquid penetration of the spray was determined via processing of images acquired from Mie back scattering under vaporizing conditions by injecting into a charge gas at elevated temperature with a 0% oxygen environment. Tests were undertaken at a gas density of 34.8 kg/m₃, 2000 bar injection pressure, and at ambient temperatures of 900, 1100, and 1300 K. Under these conditions there are noticeable fluctuations in liquid phase penetration once the steady state liquid length has been established, on the order of 10% of the mean liquid length.
Technical Paper
2013-04-08
Kiran C. Premchand, John H. Johnson, Song-Lin Yang
Numerical modeling of aftertreatment systems has been proven to reduce development time as well as to facilitate understanding of the internal physical and chemical processes occurring during different operating conditions. Such a numerical model for a catalyzed diesel particulate filter (CPF) was developed in this research work which has been improved from an existing numerical model briefly described in reference. The focus of this CPF model was to predict the effect of the catalyst on the gaseous species concentrations and to develop particulate matter (PM) filtration and oxidation models for the PM cake layer and substrate wall so as to develop an overall model that accurately predicts the pressure drop and PM oxidized during passive oxidation and active regeneration. Descriptions of the governing equations and corresponding numerical methods used with relevant boundary conditions are presented. Calibration of the model was carried out using data obtained from passive oxidation as well as active regeneration experiments conducted on a Cummins ISL diesel engine using ultra-low sulfur diesel (ULSD) fuel with 10% (B10) and 20% (B20) bio-diesel blends and equipped with a diesel oxidation catalyst (DOC)-CPF aftertreatment system.
Technical Paper
2013-04-08
Mehran Bidarvatan, Mahdi Shahbakhti
Precise cycle-to-cycle control of combustion is the major challenge to reduce fuel consumption in Homogenous Charge Compression Ignition (HCCI) engines, while maintaining low emission levels. This paper outlines a framework for simultaneous control of HCCI combustion phasing and Indicated Mean Effective Pressure (IMEP) on a cycle-to-cycle basis. A dynamic control model is extended to predict behavior of HCCI engine by capturing main physical processes through an HCCI engine cycle. Performance of the model is validated by comparison with the experimental data from a single cylinder Ricardo engine. For 60 different steady state and transient HCCI conditions, the model predicts the combustion phasing and IMEP with average errors less than 1.4 CAD and 0.2 bar respectively. A two-input two-output controller is designed to control combustion phasing and IMEP by adjusting fuel equivalence ratio and blending ratio of two Primary Reference Fuels (PRFs). The designed controller consists of a Discrete Sliding Mode Controller (DSMC) and a feed-forward integral controller.
Technical Paper
2011-05-17
Chad Walber, Jason R. Blough, Mark Johnson, Carl Anderson
When testing dynamic structures, it is important to note that the dynamic system in question may be submerged into a fluid during operation and to properly test the structure under the same condition in order to understand the true dynamic parameters of the system. In this way, the mass and stiffness coupling to the particular fluid, for the case of this study, automatic transmission fluid, may be taken into account. This is especially important in light structures where the coupling between the fluid mass and the structural mass may be great. A structure was tested with a laser vibrometer using several impact methods in open air to determine which impact method would be most suitable for submerged testing. The structure was then submerged in transmission fluid with an accelerometer attached and subsequently tested and compared to the previous results. In addition, two novel means of excitation, by use of a ball bearing impact and by use of a weighted impact rod, will also be discussed and compared.
Technical Paper
2011-04-12
Iltesham Zameer Syed, Abhijit Mukherjee, Jeffrey D. Naber
A numerical simulation of autoignition of gasoline-ethanol/air mixtures has been performed using the closed homogeneous reactor model in CHEMKIN® to compute the dependence of autoignition time with ethanol concentration, pressure, temperature, dilution, and equivalence ratio. A semi-detailed validated chemical kinetic model with 142 species and 672 reactions for a gasoline surrogate fuel with ethanol has been used. The pure components in the surrogate fuel consisted of n-heptane, isooctane and toluene. The ethanol volume fraction is varied between 0 to 85%, initial pressure is varied between 20 to 60 bar, initial temperature is varied between 800 to 1200K, and the dilution is varied between 0 to 32% at equivalence ratios of 0.5, 1.0 and 1.5 to represent the in-cylinder conditions of a spark-ignition engine. The ignition time is taken to be the point where the rate of change of temperature with respect to time is the largest (temperature inflection point criteria). The results are validated against experimental data for pressures up to 60 bar.
Technical Paper
2011-04-12
Yashodeep Lonari, Christopher Polonowski, Jeffrey Naber, Bo Chen
This paper presents the development of a Stochastic Knock Detection (SKD) method for combustion knock detection in a spark-ignition engine using a model based design approach. The SKD set consists of a Knock Signal Simulator (KSS) as the plant model for the engine and a Knock Detection Module (KDM). The KSS as the plant model for the engine generates cycle-to-cycle accelerometer knock intensities following a stochastic approach with intensities that are generated using a Monte Carlo method from a lognormal distribution whose parameters have been predetermined from engine tests and dependent upon spark-timing, engine speed and load. The lognormal distribution has been shown to be a good approximation to the distribution of measured knock intensities over a range of engine conditions and spark-timings for multiple engines in previous studies. The KDM processes these signals with a stochastic distribution estimation algorithm which outputs estimates of knock intensity and at a level characteristic of high knock and a referenced level which are then used to determine a calibrated and referenced knock factor.
Technical Paper
2011-04-12
Pranay Nagar, Scott Miers
Engine friction serves as an important domain for study and research in the field of internal combustion engines. Research shows that friction between the piston and cylinder accounts for almost 20% of the losses in an engine and therefore any effort to minimize friction losses will have an immediate impact on engine efficiency and thus vehicle fuel economy. The two most common methods to experimentally measure engine friction are the floating liner method and the instantaneous indicated mean effective pressure (IMEP) method. This paper provides a detailed review of the IMEP method, presents major findings, and discusses sources of error. Although the instantaneous IMEP method is relatively new compared to the floating liner method, it has been used by many scientists and engineers for calculating piston ring assembly friction with consistent results. It should be noted that irrespective of the method utilized, most of the experiments are conducted under motoring conditions and limited results are available for fired operation.
Technical Paper
2010-04-12
Jan Macek, Vit Dolecek, Seshasai Srinivasan, Franz Tanner, Oldrich Vitek
One-dimensional simulation methods for unsteady (transient) engine operations have been developed and published in previous studies. These 1-D methods utilize heat release and emissions results obtained from 3-D CFD simulations which are stored in a data library. The goal of this study is to improve the 1-D methodology by optimizing the control strategies. Also, additional independent parameters are introduced to extend the 3-D data library, while, as in the previous studies, the number of interpolation points for each parameter remains small. The data points for the 3-D simulations are selected in the vicinity of the expected trajectories obtained from the independent parameter changes, as predicted by the transient 1-D simulations. By this approach, the number of time-consuming 3-D simulations is limited to a reasonable amount. Boost pressure, EGR and relative A/F limit control procedures are compared to improve the engine response to speed/load requirements at minimized emission levels.
Technical Paper
2010-04-12
Iltesham Z. Syed, Yeliana Yeliana, Abhijit Mukherjee, Jeffrey D. Naber, Donna Michalek
A numerical analysis was performed to study the variation of the laminar burning speed of gasoline-ethanol blend, pressure, temperature and dilution using the one-dimensional premixed flame code CHEMKIN™. A semi-detailed validated chemical kinetic model (142 species and 672 reactions) for a gasoline surrogate fuel was used. The pure components in the surrogate fuel consist of n-heptane, isooctane and toluene. The ethanol mole fraction was varied from 0 to 85 percent, initial pressure from 4 to 8 bar, initial temperature from 300 to 600K, and the EGR dilution from 0 to 32% to represent the in-cylinder conditions of a spark-ignition engine. The laminar flame speed is found to increase with ethanol concentration and temperature but decrease with pressure and dilution. A correlation has been proposed to calculate laminar flame speeds of gasoline-ethanol/air mixtures at different pressures, temperatures, and EGR that can be used in parametric burn rate combustion models for engine simulation.
Technical Paper
2010-04-12
Y. Gong, O. Kaario, A. Tilli, M. Larmi, F.X. Tanner
Hydrotreated vegetable oil (HVO) is a high-cetane number alternative fuel with the potential of drastic emissions reductions in high-pressure diesel engines. In this study the behavior of HVO sprays is investigated computationally and compared with conventional diesel fuel sprays. The simulations are performed with a modified version of the C++ open source code OpenFOAM using Reynolds-averaged conservation equations for mass, species, momentum and energy. The turbulence has been modeled with a modified version of the RNG k-ε model. In particular, the turbulence interaction between the droplets and the gas has been accounted for by introducing appropriate source terms in the turbulence model equations. The spray simulations reflect the setup of the constant-volume combustion cell from which the experimental data were obtained. Simulations of non-evaporating and evaporating sprays have been performed for four different fuels, namely the diesel fuel DF2, n-heptane, the European-normed EN 590 fuel and the HVO fuel.
Technical Paper
2010-04-12
Fazal Syed, Swathi Nallapa, Allen Dobryden, Carrie Grand, Ryan McGee, Dimitar Filev
Environmental awareness and fuel economy legislation has resulted in greater emphasis on developing more fuel efficient vehicles. As such, achieving fuel economy improvements has become a top priority in the automotive field. Companies are constantly investigating and developing new advanced technologies, such as hybrid electric vehicles, plug-in hybrid electric vehicles, improved turbo-charged gasoline direct injection engines, new efficient powershift transmissions, and lighter weight vehicles. In addition, significant research and development is being performed on energy management control systems that can improve fuel economy of vehicles. Another area of research for improving fuel economy and environmental awareness is based on improving the customer's driving behavior and style without significantly impacting the driver's expectations and requirements. Ford Motor Company developed an adaptive real-time advisory system for fuel economy improvement in a hybrid electric vehicle that automatically identifies the driver's style, intentions and preferences and provides guidance through haptic and visual mechanisms to the driver for selecting the optimal driving strategy that results in maximum fuel economy.
Technical Paper
2010-04-12
Christopher John Polonowski, Scott Miers, Michael Lecureux, Jay Shah, Jeffrey Naber, Jeremy Worm
Exhaust gas recirculation (EGR) has been employed in a diesel engine to reduce NOx emissions by diluting the fresh air charge with gases composed of primarily N2, CO2, H2O, and O2 from the engines exhaust stream. The addition of EGR reduces the production of NOx by lowering the peak cylinder gas temperature and reducing the concentration of O2 molecules, both of which contribute to the NOx formation mechanism. The amount of EGR has been typically controlled using an open loop control strategy where the flow of EGR was calibrated to the engine speed and load and controlled by the combination of an EGR valve and the ratio of the boost and exhaust back pressures. When oxygenated biofuels with lower specific energy are used, the engine control unit (ECU) will demand a higher fuel rate to maintain power output, which can alter the volumetric flow rate of EGR. In addition, oxygenated biofuels affect the oxygen concentration in the intake manifold gas stream. The following work utilized an analytical analysis of EGR and experimental engine data to compare a soy methyl ester biodiesel (B100) to ultra-low sulfur diesel fuel (B0) with respect to EGR rate, intake air dilution and oxygen concentration, fuel consumption, brake specific NOx and particulate matter emissions in a 1.9L turbocharged DI diesel engine.
Technical Paper
2010-04-12
Venkatapathi Raju Nallapa, Fazal Syed, Jeremy Russell, Raymond Spiteri, Michelle Grytzelius, Carrie Grand, David Hoadley
Lookup tables and functions are widely used in real-time embedded automotive applications to conserve scarce processor resources. To minimize the resource utilization, these lookup tables (LUTs) commonly use custom data structures. The lookup function code is optimized to process these custom data structures. The legacy routines for these lookup functions are very efficient and have been in production for many years. These lookup functions and the corresponding data structures are typically used for calibration tables. The third-party calibration tools are specifically tailored to support these custom data structures. These tools assist the calibrators in optimizing the control algorithm performance for the targeted environment for production. Application software typically contains a mix of both automatically generated software and manually developed code. Some of the same calibration tables may be used in both auto generated and hand-code [ 1 ] [ 2 ]. Model Based Design (MBD) and Automatic Code Generation (ACG) Tools support a variety of general purpose lookup table constructs.
Technical Paper
2010-04-12
Gregory Austin, Jeffrey Naber, John H. Johnson, Chris Hutton
Active regeneration experiments were performed on a production diesel aftertreatment system containing a diesel oxidation catalyst and catalyzed particulate filter (CPF) using blends of soy-based biodiesel. The effects of biodiesel on particulate matter oxidation rates in the filter were explored. These experiments are a continuation of the work performed by Chilumukuru et al., in SAE Technical Paper No. 2009-01-1474, which studied the active regeneration characteristics of the same aftertreatment system using ultra-low sulfur diesel fuel. Experiments were conducted using a 10.8 L 2002 Cummins ISM heavy-duty diesel engine. Particulate matter loading of the filter was performed at the rated engine speed of 2100 rpm and 20% of the full engine load of 1120 Nm. At this engine speed and load the passive oxidation rate is low. The 17 L CPF was loaded to a particulate matter level of 2.2 g/L. Active regeneration was then performed using fuel dosing in the exhaust, which was oxidized at 75-80% conversion efficiency in the diesel oxidation catalyst.
Book
2005-06-27
John H. Johnson
Emission and fuel economy regulations and standards are compelling manufacturers to build ultra-low emission vehicles. As a result, engineers must develop spark-ignition engines with integrated emission control systems that use reformulated low-sulfur fuel. Emission Control and Fuel Economy for Port and Direct Injected SI Engines is a collection of SAE technical papers that covers the fundamentals of gasoline direct injection (DI) engine emissions and fuel economy, design variable effects on HC emissions, and advanced emission control technology and modeling approaches. All papers contained in this book were selected by an accomplished expert as the best in the field; reprinted in their entirety, they present a pathway to integrated emission control systems that meet 2004-2009 EPA standards for light-duty vehicles.
Book
2005-06-27
John H. Johnson
Emission and fuel economy regulations and standards are compelling manufacturers to build ultra-low emission vehicles. As a result, engineers must develop spark-ignition engines with integrated emission control systems that use reformulated low-sulfur fuel. Combustion & Emission Control for SI Engines: Modeling and Experimental Studies is a collection of SAE technical papers that covers advanced emission measurements, combustion, exhaust after- treatment systems, fuel and lubricant effects on emissions, modeling of in-cylinder processes, and particle control and measurement. All papers contained in this book were selected by an accomplished expert as the best in the field; reprinted in their entirety, they present a pathway to integrated emission control systems that meet 2004-2009 EPA standards for light-duty vehicles.
Book
2005-06-17
John H. Johnson
This comprehensive set includes Emissions Control and Fuel Economy for Port and Direct Injected SI Engines and Combustion & Emission Control for SI Engines. Emissions Control and Fuel Economy for Port and Direct Injected SI Engines is a collection of 45 SAE technical papers that cover the fundamentals of gasoline direct injection (DI) engine emissions and fuel economy, design variable effects on HC emissions, and advanced emission control technology and modeling approaches. Combustion & Emission Control for SI Engines: Modeling and Experimental Studies is a collection of 45 SAE technical papers that covers advanced emission measurements, combustion, exhaust after-treatment systems, fuel and lubricant effects on emissions, modeling of in-cylinder processes, and particle control and measurement. Emissions Control and Fuel Economy for Port and Direct Injected SI Engines Combustion & Emission Control for SI Engines
Technical Paper
2002-05-06
Ossi Kaario, Martti Larmi, Franz Tanner
Three-dimensional diesel engine combustion simulations with single-step chemistry have been compared with two-step and three-step chemistry by means of the Laminar and Turbulent Characteristic Time Combustion model using the Star-CD program. The second reaction describes the oxidation of CO and the third reaction describes the combustion of H2. The comparisons have been performed for two heavy-duty diesel engines. The two-step chemistry was investigated for a purely kinetically controlled, for a mixing limited and for a combination of kinetically and mixing limited oxidation. For the latter case, two different descriptions of the laminar reaction rates were also tested. The best agreement with the experimental cylinder pressure has been achieved with the three-step mechanism but the differences with respect to the two-step and single-step reactions were small. Also, the maximum and mean gas temperatures, and hence the NOx, were not noticeably affected by the different choices of chemistry.
Book
2002-04-25
The focus of this book is on measurement techniques, fundamentals of NOx formation in the engine, exhaust gas recirculation (EGR), aftertreatment controls, fuel injection variables that lower NOx emissions, and fuel effects on NOx and particulate emissions. Diesel Nitrogen Oxide Emissions: Landmark Research 1995-2001 is based on extensive SAE literature from the past six years and is the first SAE Progress in Technology book published on the topic of measurement and control of diesel nitrogen oxide emissions. The papers in this book have been chosen as the most valuable on this topic.
Technical Paper
2002-03-04
Walter W. Olson, John W. Sutherland
The National Science Foundation recently sponsored a Workshop on Environmentally Benign Manufacturing (EBM) for the Transportation Industries. The objective of the workshop was to determine future directions of research in the EBM area and to construct a roadmap for development of future research programs. While research in the fields of Design for the Environment (DfE) and Life Cycle Analysis (LCA) have focused on the product and product life cycles, an additional focus is needed to find and develop processes with less environmental impact within the manufacturing environment. This workshop explored EBM issues with respect to the enterprise, the products, the processes and the materials.
Technical Paper
2002-03-04
Ossi Kaario, Martti Larmi, Franz Tanner
A modified version of the Laminar and Turbulent Characteristic Time combustion model and the Hiroyasu-Magnussen soot model have been implemented in the flow solver Star-CD. Combustion simulations of three DI diesel engines, utilizing the standard k-ε turbulence model and a modified version of the RNG k-ε turbulence model, have been performed and evaluated with respect to combustion performance and emissions. Adjustments of the turbulent characteristic combustion time coefficient, which were necessary to match the experimental cylinder peak pressures of the different engines, have been justified in terms of non-equilibrium turbulence considerations. The results confirm the existence of a correlation between the integral length scale and the turbulent time scale. This correlation can be used to predict the combustion time scale in different engines. It was found that, although the standard k-ε turbulence model produced adequate results for the larger engines, the RNG turbulence model gave better agreement with the experimental data for all engines.
Technical Paper
2002-03-04
Karl Haapala, Aaron Thul, Steve Andrasko, Christian Muehlfield, Brandon Bloss, Richard Nesbitt, John E. Beard
In this paper, the conversion of a production SUV to a hybrid electric vehicle with a drive system utilizing a planetary power-split transmission is presented. The uniqueness of this design comes from its ability to couple the advantages of a parallel hybrid with the advantages of a series hybrid. Depending on operating conditions and recent operating history, the drive system transitions to one of several driving modes. The drive system consists of a planetary gear set coupled to an alternator, motor, and internal combustion engine. It performs the power-split operation without the need for belt drives or clutching devices. The effects on driveability, manufacturing, fuel economy, emissions, and performance are presented along with the design, selection, and implementation of all of the vehicle conversion components.
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