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SAE 2011 High Efficiency IC Engines Symposium - Session 3 - Advanced Diesel Engine Technologies Presenter Andrew Brown, Delphi Corp.

Vehicle electrification is shaping the future of automotive mobility in terms of automotive power and propulsion. The market for New Energy Vehicles (HEV/PHEV/REEV/EV) as well as clean vehicle technologies is expected to grow steadily driven by government regulations mandating increased fuel economy and lower emissions. The fastest growth in this market will be in Asia Pacific, most notably China. The Chinese government has made its intentions clear on how important it considers the development and consumer purchase of hybrid and electric vehicles. The mandate is that by year 2012, vehicle manufacturers produce at least 500,000 units (or 5%) per year of their total output as hybrid and/or electric. All Chinese vehicle manufacturers must have at least one HEV or EV model in the market by the same year. Thus far China has invested over US$3.5 billion to stimulate the production of NEVs and the necessary infrastructure to support them.

Intake camshaft retard beyond that necessary for reliable cold start-ability is shown to improve part-load fuel economy. By retarding the intake camshaft timing, engine pumping losses can be reduced and fuel economy significantly improved. At high engine speeds, additional intake cam retard may also improve full-load torque and power. To achieve these benefits, an intake camshaft phaser with intermediate lock pin position (ILP) and increased phaser authority was developed. ILP is necessary to reliably start at the intermediate phase position for cold temperatures, while providing increased phaser retard under warm conditions. The phaser also provides sufficient intake advance to maximize low-speed torque and provides good scavenging for boosted engine applications. Design and development of the intermediate locking phaser system is described. The pros and cons of various methods of accomplishing locking and unlocking a phaser are illustrated.

A complete system approach to power semiconductor analysis and selection is set forth in this paper. In order to address design overkill, a suitable power profile across the desired drive schedule is obtained through vehicle simulation in lieu of worse case operating conditions. The representative profile is then applied to detailed models of the inverter, power device, and power device thermal stack-up in order to predict worse case, silicon junction temperature rise. The simulation stream includes a closed silicon thermal loop that leads to more accurate power loss and junction temperature calculations. The models are combined and exercised in a single platform for ease of integration and fast simulation. Herein, the methods will be applied to a working example of an inverter for motor drives, and analytical results will be reviewed.

This paper describes a method to estimate the engine stop position using any production style crank position sensor, while accounting for possible engine rock-back. The approach is based on modeling the engine speed state, achieving robustness and ease of calibration by adapting the rubbing friction model component during the first part of engine coast-down, followed by open-loop modeling when the engine speed has dropped below the sensor signal validity threshold.

This paper presents production Engine Management System algorithms for Estimation and Control of Turbocharged engines with the following qualities; 1) Model based ensuring applicability at all ambient conditions, 2) Does not require Turbine data for calibration 3) Estimation logic form allows reuse for control applying predictive values for response and stability 4) Applies to all Waste-Gate types; passive and active, pneumatic and electrical, 5) Does not require Waste-Gate position measurement 5) Applies to engines with Variable Geometry Turbine.

This paper addresses the longstanding problems of residual gas measurement during engine dynamometer testing, and of real-time residual modeling for engine control applications. A new method is described which is simple to apply, requiring only currently standard calibration test cell instrumentation. Experimental validation against measurements using direct in-cylinder CO2 sampling is presented, and a comprehensive error sensitivity analysis is included. A real-time capable, controls-oriented model is also described. Its accuracy is assessed by comparison to engine-simulation-generated residual values after using these values to determine the model parameters.

This paper is an overview of the current state (calendar year 2010) of in-vehicle multiplexing and what pertinent technologies are emerging. Usage and trends of in-vehicle networking protocols will be presented and categorized. The past few years have seen a large growth in the number and type of communication buses used in automobiles, trucks, construction equipment, and military, among others. Development continues even into boating and recreation vehicles. Areas for discussion will include SAE Class A, B, C, Diagnostics, SafetyBus, Mobile Media, Wireless, and X-by-Wire. All existing mainstream vehicular multiplex protocols (approximately 40) are categorized using the SAE convention as well as categories previously proposed by this author. Top contenders will be pointed out along with a discussion of the protocol in the best position to become the industry standard in each category.

The current study focused on the effects B20 fuel (20% soybean-based biodiesel) and SCR entrance shapes on a light-duty, high-speed, 2.8L common-rail 4-cylinder diesel engine, at different exhaust temperatures. The results indicate that B20 has less deNOX efficiency at low temperature than ULSD, and that N₂O emission need to be characterized as well as NH₃ slip. If a mixer and enough mixing length are used, longer divergence section does not improve the deNOX efficiency significantly under the speed ranges tested.

Estimation of vehicle roll angle, lateral velocity and side slip angle for the purpose of crash sensing is considered. Only roll rate sensor and the sensors readily available in vehicles equipped with ESC (Electronic Stability Control) systems are used in the estimation process. The algorithms are based on kinematic relationships, thus avoiding dependence on vehicle and tire models, which minimizes tuning efforts and sensitivity to parameter variations. The estimate of roll angle is obtained by blending two preliminary estimates, each valid in different conditions, in such a manner that the final estimate continuously favors the more accurate one. The roll angle estimate is used to compensate the gravity component in measured lateral acceleration due to vehicle roll or road bank angle. This facilitates estimation of lateral velocity and side slip angle from fundamental kinematic relationships involving the gravity-compensated lateral acceleration, yaw rate and longitudinal velocity.

Brazilian ethanol vehicles are typically equipped with an auxiliary gasoline sub-tank fuel system which aids cold starting and drivability for low ambient temperatures. Port fuel injectors capable of rapidly heating ethanol have been developed to eliminate this auxiliary system. These injectors also enable reductions in emissions. Computational Fluid Dynamics (CFD) is used in conjunction with Taguchi Robust Engineering methods to optimize the heat exchanging geometry of these heated injectors. Simulation results are confirmed with experimental hardware and engine cold start testing. Modeling results, experimental hardware, and engine cold start performance is presented and discussed.

Signal processing incorporating Artificial Neural Networks (ANN) has been shown to be well suited for modeling engine-related performance indicators [ 1 , 2 , 3 ] that require multi-dimensional parametric calibration space. However, to obtain acceptable accuracy, traditional ANN implementation may require processing resources beyond the capability of current engine controllers. This paper explores the practicality of implementing an ANN-based algorithm performing real-time calculations of the volumetric efficiency (VE) for an engine with variable valve actuation (phasing and lift variation). This alternative approach was considered attractive since the additional degree of freedom introduced by variable lift would be cumbersome to add to the traditional multi-dimensional table-based representation of VE.

Compressed Natural Gas (CNG) is gaining popularity as a viable alternate transportation fuel in many regions of the world. Injectors capable of delivering pressurized gaseous fuels have been developed for this emerging vehicular market segment. CNG fuel injectors must be designed to be compatible and durable with a very low lubricity gaseous fuel to meet automotive OEM life expectancy standards. Traditional gasoline injectors utilize a “hard/hard” sealing configuration, in which both the valve and seat are constructed out of hard metals. When properly lubricated with liquid fuels, these valves can meet vehicular injector leak and flow durability requirements. However, metal valves operating without lubrication can experience excessive wear, which leads to unacceptable levels of gas leakage and flow shifts. The use of elastomer-to-metal sealing surfaces minimizes leakage, but may cause cold ambient operation challenges.

Samples of 33% glass filled and unfilled poly(butylene terephthalate) [PBT] and nylon 66 (PA66) were injection molded into bars,which were immersed in common engine and powertrain fluids: antifreeze, motor oil and automatic transmission fluid for 25 days. Fluid uptake was measured at 1, 7, 18, and 25 days by gravimetry. Both PBT samples absorbed 0.2-0.25% antifreeze and 0.05 - 0.10% motor oil and automatic transmission fluid (ATF). Both DSC and DMA analysis showed no disruption of polymer thermal transitions or storage moduli. The glass filled PA66 sample absorbed 2.5% antifreeze and 0.25-0.3% of motor oil and ATF and showed an 80°C reduction in the tan delta maximum on DMA. The unfilled PA66 sample absorbed 7% antifreeze and 0.2-0.3% of motor oil and ATF also showed a tan delta maximum 80°C less than the unexposed control. Creep analysis was conducted on the unfilled nylon sample and compared to a virgin material.

Gasoline direct injection (GDi) engines have become popular due to their inherent potential for reduction of exhaust emissions and fuel consumption to meet increasingly stringent environmental standards. These engines require high-pressure fuel injection in order to improve the fuel atomization process and accelerate mixture preparation. To achieve a lower-cost system, a single-piston high-pressure fuel pump design is often employed due to its relative simplicity. However, pumps of this design are acknowledged as the source of high levels of fuel pressure fluctuations which can lead to audible noise, variations in the amount and spray quality of fuel delivery from cylinder to cylinder, compromised durability and consumer dissatisfaction. In this paper, the design process for a high-pressure fuel rail assembly using Robust Engineering methodology is presented.

As more and more active restraint devices are added by vehicle manufacturers for occupant protection, the history of driver frontal airbags illustrates that the design performance of such devices for in-position (IP) occupants often have to be limited in order to reduce their aggressiveness for out-of-position (OOP) situations. As of today, a limited number of publications dealing with FE simulation of airbag deployment for OOP are available. The objective of our study was to evaluate the feasibility of airbag deployment simulations based on an extensive set of well-defined physical test matrix. A driver frontal airbag was chosen (European mid-size car sample) for this study. It was deployed against a force plate (14 tests in a total of 6 configurations), and used with Hybrid III 50th percentile dummy (HIII) in OOP tests (6 tests, 4 configurations). Special attention was paid to control the boundary conditions used in experiments in order to improve the modelling process.

This book features 20 SAE technical papers, originally published in 2009 and 2010, which showcase how the mobility industry is developing greener products and staying responsive - if not ahead of - new standards and legal requirements. These papers were selected by SAE International's 2010 President Dr. Andrew Brown Jr., Executive Director and Chief Technologist for Delphi Corporation. Authored by international experts from both industry and academia, they cover a wide range of cutting-edge subjects including powertrain electrification, alternative fuels, new emissions standards and remediation strategies, nanotechnology, sustainability, in-vehicle networking, and how various countries are also stepping up to the "green challenge".

During the past decade, there has been a steady increase in studies addressing rollover crashes and injuries. Though rollovers are not the most frequent crash type, they are significant with respect to serious injury and interest in rollovers has grown with the introduction of SUVs, vans, and light trucks. A review of Occupant and Vehicle Responses in Rollovers examines relevant conditions for field roll overs, vehicle responses, and occupant kinetics in the vehicle. This book edited by Dr. David C. Viano and Dr. Chantal S. Parenteau includes 62 technical documents covering 15 years of rollover crash safety, including field crash statistics, pre- and rollover dynamics, test procedures and dummy responses.