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Technical Paper

Vehicle Trajectories After Intersection Collision Impact

1970-02-01
700176
The postcollision motion starts immediately upon completion of a collision impact where the vehicles obtain new sets of velocities through an exchange of momentum. Similitude with model study and fullscale automobile experiments indicate that the post-collision trajectory is essentially a plane motion, governed by inertia and tire friction. Trajectories depend on many parameters (such as tire friction coefficient, front wheel steering angle, vehicle geometrics, and whether wheels are locked or free to rotate) but not on the vehicle weight. Theoretical computation of trajectories are compared with experiments.
Technical Paper

The Performance Effects of Edge-Based Heat Transfer on Lithium-Ion Pouch Cells Compared to Face-Based Systems

2014-04-01
2014-01-1866
Optimizing the hardware design and control strategies of thermal management systems (TMS) in battery packs using large format pouch cells is a difficult but important problem due to the limited understanding of how internal temperature distributions impact the performance and lifetime of the pack. Understanding these impacts is difficult due to the greatly varying length and time scales between the coupled phenomena, causing the need for complex and computationally expensive models. Here, an experimental investigation is performed in which a set of fixed one-dimensional temperature distributions are applied across the face of a Nickel-Cobalt-Manganese (NCM) cathode lithium ion pouch cell in order to study the performance impacts. Effects on the open circuit voltage (OCV), Ohmic resistance, bulk discharge and charge resistance and instantaneous power are investigated.
Technical Paper

Simulating a Complete Performance Map of an Ethanol-Fueled Boosted HCCI Engine

2015-04-14
2015-01-0821
This paper follows a cycle-simulation method for creating an engine performance map for an ethanol fueled boosted HCCI engine using a 1-dimensional engine model. Based on experimentally determined limits, the study defined operating conditions for the engine and performed a limited parameter sweep to determine the best efficiency case for each condition. The map is created using a 6-Zone HCCI combustion model coupled with a detailed chemical kinetic reaction mechanism for ethanol, and validated against engine data collected from a 1.9L 4-Cylinder VW TDI engine modified to operate in HCCI mode. The engine was mapped between engine speeds of 900 and 3000 rpm, 1 and 3 bar intake pressure, and 0.2 and 0.4 equivalence ratio, resulting in loads between idle and 14.0 bar BMEP. Analysis of a number of trends for this specific engine map are presented, such as efficiency trends, effects of combustion phasing, intake temperature, engine load, engine speed, and operating strategy.
Journal Article

Regulated Emissions, Air Toxics, and Particle Emissions from SI-DI Light-Duty Vehicles Operating on Different Iso-Butanol and Ethanol Blends

2014-04-01
2014-01-1451
Gasoline direct injection (GDI) engines have improved thermodynamic efficiency (and thus lower fuel consumption) and power output compared with port fuel injection (PFI) and their penetration is expected to rapidly grow in the near future in the U.S. market. In addition, the use of alternative fuels is expanding, with a potential increase in ethanol content beyond the current 10%. Increased emphasis has been placed on butanol due to its more favorable fuel properties, as well as new developments in production processes. This study explores the influence of mid-level ethanol and iso-butanol blends on criteria emissions, gaseous air toxics, and particulate emissions from two wall-guided gasoline direct injection passenger cars fitted with three-way catalysts. Emission measurements were conducted over the Federal Test Procedure (FTP) driving cycle on a chassis dynamometer.
Technical Paper

Potential for Closed Loop Air-Fuel Ratio Management of a Diesel Engine

1999-03-01
1999-01-0517
The potential for improving the efficiency of a heavy duty turbocharged diesel engine by closed loop Air-Fuel Ratio (AFR) management has been evaluated. Testing conducted on a 12 liter diesel engine, and subsequent data evaluation, has established the feasibility of controlling the performance through electronic control of air management hardware. Furthermore, the feasibility of using direct in-cylinder pressure measurement for control feedback has been established. A compact and robust fiber optics sensor for measuring real time in-cylinder pressure has been demonstrated on a test engine. A preferred method for reducing the cylinder pressure data for control feedback has been established for continued development.
Technical Paper

Meeting Both ZEV and PNGV Goals with a Hybrid Electric Vehicle - An Exploration

1996-08-01
961718
This paper is written to provide information on the fuel efficiency, emissions and energy cost of vehicles ranging from a pure electric (ZEV) to gasoline hybrid vehicles with electric range varying from 30 mi (50km) to 100 mi (160km). The Federal government s PNGV and CARB s ZEV have different goals, this paper explores some possibilities for hybrid-electric vehicle designs to meet both goals with existing technologies and batteries. The SAE/CARB testing procedures for determining energy and emission performance for EV and HEV and CARB s HEV ruling for ZEV credit are also critically evaluated. This paper intends to clarify some confusion over the comparison, discussion and design of electric- hybrid- and conventional- vehicles as well.
Journal Article

Evaluation and Modification of Constant Volume Sampler Based Procedure for Plug-in Hybrid Electric Vehicle Testing

2011-08-30
2011-01-1750
Plug-in hybrid electric vehicles (PHVs) consume both fossil fuel and grid electricity, which imposes emission testing challenges on the current constant volume sampler (CVS) test method. One reason is that in the charge-depleting cycle, PHVs having all-electric range operate the engine for a small portion of the traction energy need, causing the CVS to overdilute the exhaust gas. The other reason is that the dilution factor (DF) in the EPA calculation has an error caused by ignoring the CO₂ concentration in ambient air. This paper evaluates these challenges by testing a Toyota PHV on the industry standard CVS system combined with additional continuous sampling methodology for continuous diluents, smooth approach orifice (SAO) measurement for ambient air flow, and fuel flow meter (FFM) measurement for fuel consumption. The current EPA DF can produce an error resulting in higher mass calculation.
Technical Paper

Evaluating Particulate Emissions from a Flexible Fuel Vehicle with Direct Injection when Operated on Ethanol and Iso-butanol Blends

2014-10-13
2014-01-2768
The relationship between ethanol and iso-butanol fuel concentrations and vehicle particulate matter emissions was investigated. This study utilized a gasoline direct injection (GDI) flexible fuel vehicle (FFV) with wall-guided fueling system tested with four fuels, including E10, E51, E83, and an iso-butanol blend at a proportion of 55% by volume. Emission measurements were conducted over the Federal Test Procedure (FTP) driving cycle on a chassis dynamometer with an emphasis on the physical and chemical characterization of particulate matter (PM) emissions. The results indicated that the addition of higher ethanol blends and the iso-butanol blend resulted in large reductions in PM mass, soot, and total and solid particle number emissions. PM emissions for the baseline E10 fuel were characterized by a higher fraction of elemental carbon (EC), whereas the PM emissions for the higher ethanol blends were more organic carbon (OC) in nature.
Technical Paper

Emission Control Cost-Effectiveness of Alternative-Fuel Vehicles

1993-08-01
931841
Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquified petroleum gas, compressed natural gas, and electricity. Vehicle emission estimates included both exhaust and evaporative emissions for air pollutants of hydrocarbon, carbon monoxide. nitrogen oxides, and air-toxic pollutants of benzene, formaldehyde, 1,3-butadiene, and acetaldehyde. Vehicle life-cycle cost estimates accounted for vehicle purchase prices, vehicle life, fuel costs, and vehicle maintenance costs.
Journal Article

Electrical Architecture Optimization and Selection - Cost Minimization via Wire Routing and Wire Sizing

2014-04-01
2014-01-0320
In this paper, we propose algorithms for cost minimization of physical wires that are used to connect electronic devices in the vehicle. The wiring cost is one of the most important drivers of electrical architecture selection. Our algorithms perform wire routing from a source device to a destination device through harnesses, by selecting the optimized wire size. In addition, we provide optimized splice allocation with limited constraints. Based on the algorithms, we develop a tool which is integrated into an off-the-shelf optimization and workflow system-level design tool. The algorithms and the tool provide an efficient, flexible, scalable, and maintainable approach for cost analysis and architecture selection.
Technical Paper

Easily Verifiable Adaptive Sliding Mode Controller Design with Application to Automotive Engines

2016-04-05
2016-01-0629
Verification and validation (V&V) are essential stages in the design cycle of industrial controllers to remove the gap between the designed and implemented controller. In this study, a model-based adaptive methodology is proposed to enable easily verifiable controller design based on the formulation of a sliding mode controller (SMC). The proposed adaptive SMC improves the controller robustness against major implementation imprecisions including sampling and quantization. The application of the proposed technique is demonstrated on the engine cold start emission control problem in a mid-size passenger car. The cold start controller is first designed in a single-input single-output (SISO) structure with three separate sliding surfaces, and then is redesigned based on a multiinput multi-output (MIMO) SMC design technique using nonlinear balanced realization.
Technical Paper

Development of a Carbon/Epoxy Body for a High Performance Vehicle

2003-03-03
2003-01-1195
Considerations follow [1] on the development of the carbon/epoxy body of the Lamborghini Murcièlago. Laminate lay-up and material selection for stiffness criteria are reviewed. Engineering solutions for tooling operations in order to achieve class A surface certification are analyzed. Design for environmental aging is also discussed and accelerated degradation testing methods are described. Finally, the program that lead to the adoption of hybrid adhesive bonding as sole method of joining the composite body components to the tubular steel frame is reviewed.
Technical Paper

A Fuel Control Strategy that Optimizes the Efficiency of a Direct-Methanol Fuel Cell in an Automotive Application

1999-08-17
1999-01-2913
For automotive applications, it is necessary to maximize the fuel conversion efficiency of a PEM direct-methanol fuel cell (DMFC) over the broadest possible dynamic range of power. The research reported here critically examines the efficiency of the DMFC stack when operated over a broad power range. This research establishes a basis for a control strategy that simultaneously: optimizes DMFC fuel conversion efficiency versus power level, leads into a system level optimization of efficiency vs. power, and provides an operational strategy for controlling a direct-methanol fuel cell for maximum fuel efficiency from minimum to maximum power demand. First, there is an explanation of the experimental conditions used to obtain the DMFC experimental data that is reported and analyzed. Next the DMFC methanol crossover phenomenon is discussed and characterized. Then the conceptual framework for the optimization of fuel conversion efficiency is presented.
Journal Article

A Complete Assessment of the Emissions Performance of Ethanol Blends and Iso-Butanol Blends from a Fleet of Nine PFI and GDI Vehicles

2015-04-14
2015-01-0957
Biofuels, such as ethanol and butanol, have been the subject of significant political and scientific attention, owing to concerns about climate change, global energy security, and the decline of world oil resources that is aggravated by the continuous increase in the demand for fossil fuels. This study evaluated the potential emissions impacts of different alcohol blends on a fleet of modern gasoline vehicles. Testing was conducted on a fleet of nine vehicles with different combinations of ten fuel blends over the Federal Test Procedure and Unified Cycle. The vehicles ranged in model year from 2007-2014 and included four vehicles with port fuel injection (PFI) fueling and five vehicles with direct injection (DI) fueling. The ten fuel blends included ethanol blends at concentrations of 10%, 15%, 20%, 51%, and 83% by volume and iso-butanol blends at concentrations of 16%, 24%, 32%, and 55% by volume, and an alcohol mixture giving 10% ethanol and 8% iso-butanol in the final blend.
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