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A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.

A 1990 Ford Taurus operated on reformulated gasoline was tested under three modes of malfunction: disabled heated exhaust gas oxygen (HEGO) sensor, inactive catalytic converter, and controlled misfire. The vehicle was run for four U.S. EPA UDDS driving schedule (FTP-75) tests at each of the malfunction conditions, as well as under normal operating conditions. An extensive set of emissions data were collected. In addition to the regulated emissions (HC, CO, and NOx), a detailed chemical analysis was carried out to determine the gas- and particle-phase non-regulated emissions. The effect of vehicle malfunction on gas phase emissions was significantly greater than it was on particle phase emissions. For example, CO emissions ranged from 2.57 g/mi (normal operation) to 34.77 g/mi (disable HEGO). Total HCs varied from 0.22 g/mi (normal operation) to 2.21 g/mi (blank catalyst). Emissions of air toxics (1,3-butadiene, benzene, acetaldehyde, and formaldehyde) were also significantly effected.

Recent Federal and California legislation have mandated major improvements in emission control. Tailpipe HC emission must be decreased an order of magnitude for the California Ultra Low Emission Vehicle (ULEV) standard. Present feedback A/F* control systems employ a Heated Exhaust Gas Oxygen sensor (HEGO sensor) upstream of the catalyst to perform A/F feedback control. Limitations on the ultimate accuracy of these switching sensors are well known. To overcome these limitations a linear Universal Exhaust Gas Oxygen sensor (UEGO sensor) placed downstream from the minicatalyst is employed to attain improved A/F control and therefore, higher three-way catalyst (TWC) conversion efficiency. This configuration was granted a patent in 1992 (1**). This study compares performance differences between the two feedback control systems on a Ford Mustang. In initial studies both the UEGO and HEGO sensors were compared at the midposition location downstream of a minicatalyst.

Afterburning of a rich exhaust/air mixture ahead of the catalyst has been shown in earlier papers to offer an effective means of achieving catalyst light-off in very short times. Protection of the catalyst from overheating is an important aspect of systems using EGI, and on board diagnostics will be required to check for proper function of EGI. In this paper, some options for these requirements are discussed, using a high temperature linear thermistor.

A new laboratory test for measuring catalyst oxygen storage capacity has been developed. The test accurately predicts catalyst performance on the vehicle during transient A/F excursions and correlates well with vehicle CO and Nox tailpipe emissions. The test was subsequently used to facilitate improved oxygen storage capacity for new Pd-only washcoat formulations.

The present work focused on modeling turbulent flame propagation combustion process using a direct chemical kinetics model. Firstly, the theory of turbulent flame propagation combustion modeling directly using chemical kinetics is given in detail. Secondly, two important techniques in this approach are described. One technique is the selection of chemical kinetics mechanism, and the other one is the selection of AMR (adaptive mesh refinement) level. A reduced chemical kinetics mechanism with minor modification by the authors of this paper which is suitable for simulating gasoline engine under warm up operating conditions was selected in this work. This mechanism was validated over some operating conditions close to some engine cases. The effect of AMR level on combustion simulation is given, and an optimum AMR level of both velocity and temperature is recommended.

This paper provides an overview of the dual EGO sensor method for OBD-II catalyst efficiency monitoring. The processes governing the relationship between catalyst oxygen storage, HC conversion efficiency, and rear EGO sensor response are reviewed in detail. A simple physical model relating catalyst oxygen storage capacity and rear EGO sensor response is constructed and used in conjunction with experimental data to provide additional insight into the operation of the catalyst monitor. The effect that the catalyst washcoat formulation has in determining the relationship between catalyst oxygen storage capacity and HC conversion efficiency and its impact on the catalyst monitor is also investigated. Lastly, the effects of catalyst failure mode, fuel sulfur, and the fuel additive MMT on the catalyst monitor's ability to properly diagnose catalyst function are discussed.

The optimized design of an exhaust emission system in terms of performance, cost, packaging, and engine control strategy will be a key part of competitively meeting future more stringent emission standards. Extensive use of vehicle experiments to evaluate design system tradeoffs is far too time consuming and expensive. Imperative to successfully meeting the challenges of future emission regulations and cost constraints is the development of an exhaust system simulation model which offers the ability to sort through major design alternatives quickly while assisting in the interpretation of experimental data. Previously, detailed catalyst models have been developed which require the specification of intricate kinetic mechanisms to determine overall catalyst performance. While yielding extremely valuable results, these models use complex numerical algorithms to solve multiple partial differential equations which are time consuming and occasionally numerically unstable.

Manual Materials Handling has been historically recognized as one of the more prevalent causes for work related lost time injuries. Many manufacturing facilities use Material Handling Systems (lift/ tilt tables, hoists, articulated arms), often to alleviate ‘ergonomic’ stressors as well as to optimize production. If not used appropriately, Material Handling Systems can create new ergonomic concerns, or in some cases increase the physical demands of a job. A strategy designed to optimize the fit between the operator, the appropriate equipment and the operation is addressed in this paper.

The characteristics of multiple spark ignition systems with respect to engine performance, emissions, lean misfire, and tolerance to exhaust gas recirculation (EGR) have been investigated using a carbureted single-cylinder engine. The results, which were compared to those obtained with a standard single spark ignition system, show that both lean misfire limit and EGR tolerance are extended with the multiple spark system. The amount of extension varies with engine load, being largest at the lighter loads studied. Engine power and emissions at non-misfiring conditions are the same with both ignition systems.

This paper discusses the testing for retentivity of non-volatile memories. The physics associated with the reliable production of various non-volatile data storage devices has long been a topic of debate. The ability to reliably produce devices which endure erase/write cycling and retain data for extended periods of time has been questionable. Recent improvements in IC processing has given rise to claims of enhancements in both of these areas. Non-volatile memories are attractive in many automotive electronic applications where battery backup is neither convenient or feasible, but because of reliability concerns they have not found their way into critical applications. In applications like odometer or emission control calibrations it is imperative that memory retention is assured. In order to verify the reliability of the various available non-volatile memory devices, an accelerated test program was instituted.

Fuel efficient engine oils containing molybdenum dialkyldithiocarbamate, MoDTC, friction modifiers can lose their ability to reduce friction during service prematurely. Depletion processes involving antioxidant reactions and interactions with other additives play important roles in determining the performance of these formulations. This paper describes results from investigations of the antioxidant reactions of MoDTC alone and in combinations with zinc dialkyldithiophosphates and a phenolic antioxidant. The effect of supplementary ashless antioxidant on retention of friction reducing capability is described.

A study was carried out to increase our understanding of the emissions of air toxics from normal and high-emitting vehicles. This study is part of a larger study on fuel effects in high-emitting vehicles, and is part of the Auto/Oil Air Quality Improvement Research Program (AQIRP). Detailed measurements were carried out on the emissions of two vehicles run on industry-average gasoline. The two vehicles, having similar emissions control technologies, represent a high-emitting vehicle and a normal-emitting vehicle. In addition to the regulated emissions (HC, CO, and NOx), a detailed chemical analysis was carried out on the gas - and particle-phase non-regulated emissions. The vehicles were tested over the U.S. EPA UDDS driving schedule. The high emitter was highly variable with regard to emissions, but always operated rich of the stoichiometric point. Up to 46% of fuel carbon was emitted as CO and unburned HC for the high emitter, compared to less than 1.4% for the normal emitter.

Various methods are available to predict future cylinder air charge for improved air/fuel control. However, there can never be perfect prediction. This paper presents an algorithm to correct for imperfect cylinder charge prediction. This is done by expanding the air/fuel control boundary to include the catalyst, and correcting prediction errors as soon as possible using small corrective changes to later cylinder fuel inputs. The method was experimentally tested and showed improved air/fuel control as indicated by reduced variability of catalyst downstream air/fuel ratio. Additional vehicle testing showed potential to further reduce emissions.

Magnesium die-cast alloys are known to have a layered microstructure composed of: (1) An outer skin layer characterized by a refined microstructure that is relatively defect-free; and (2) A “core” (interior) layer with a coarser microstructure having a higher concentration of features such as porosity and externally solidified grains (ESGs). Because of the difference in microstructural features, it has been long suggested that removal of the surface layer by machining could result in reduced mechanical properties in tested tensile samples. To examine the influence of the skin layer on the mechanical properties, a series of round tensile bars of varying diameters were die-cast in a specially-designed mold using the AM60 Mg alloy. A select number of the samples were machined to different final diameters. Subsequently, all of the samples (as-cast as well as machined) were tested in tension.

Future European air quality standards for light duty diesel vehicles will include stringent NOx emission regulations. In order to meet these regulations, a lean NOx catalyst system may be necessary. Since the catalytic removal of NOx is very difficult with the large concentration of oxygen present in diesel exhaust, a reductant is usually added to the exhaust to increase the NOx conversion. This paper describes a lean NOx catalyst system for a Transit light-duty truck which uses a reductant solution of urea in water. In this work, a microprocessor was used to vary the amount of the reductant injected depending on the operating conditions of a 2,5 L naturally aspirated HSDI engine. The NOx conversions were 60% and 80% on the current European driving cycle and the U.S. FTP cycles, respectively. Data on the emissions of HC, CO, NOx, particulate mass and composition, individual HC species, aldehydes, PAH and most HC species were evaluated.

Imposing tensile stress on an edge of a sheet metal blank is a common condition in many sheet metal forming operations, making edge formability a very important factor to consider. Because edge formability varies greatly among different materials, cutting methods (and their control parameters), it is very important to have access to an experimental technique that would allow for quick and reliable evaluation of edge formability for a given case. In this paper, two existing techniques are compared: the hole expansion test and the tensile test. It is shown that the hole expansion test might not be adequate for many cases, and is prone to overestimating the limiting strain, because the burr on the sheared edge is typically smaller than what is observed in production. The tensile test represents an effective alternative to the hole expansion test. Advantages and disadvantages of each case are discussed.

Catalyzed hydrocarbon traps have shown promise in reducing cold-start tailpipe hydrocarbon emissions from gasoline powered vehicles. In this paper, we report the use of catalyzed hydrocarbon trap technology to reduce the non-methane hydrocarbon emissions from a flex-fuel vehicle that can operate on fuel mixtures ranging from pure gasoline to 85% ethanol/15% gasoline. We have found that hydrocarbon traps show a substantially greater reduction in hydrocarbon emissions when used with ethanol fuel than with gasoline. We present laboratory and vehicle test results that show that tailpipe non-methane hydrocarbon emissions from a flex-fuel vehicle can be reduced by 43% when using 85% ethanol/15% gasoline fuel and 16% when using gasoline fuel from a baseline exhaust system using a three-way catalyst. These results were obtained using a catalyzed hydrocarbon trap specifically formulated for use with ethanol fuel.

All automotive brake linings have mechanical strength and thermal expansion properties which vary with orientation. This paper describes laboratory equipment and test procedures which characterize lining strength and expansion behavior, using small specimens. A benchtop testing device is introduced which can be used to perform shear and tensile tests on lining samples and singly-riveted lining assemblies. Results are presented for a representative group of production and experimental linings. Applications are discussed.

In 1958 the Coordinating Research Council conducted an extensive series of vapor lock road tests at a centralized location to study the effect of test variables on the hot fuel handling characteristics of passenger cars. Two years later, another test program was carried out at a common location to determine the hot fuel handling characteristics of a selected group of 1960 cars, employing the vapor lock survey technique developed in the 1958 program. The results obtained from the two programs indicate that this technique provides a satisfactory basis for defining the more severe vapor handling characteristics of automobiles in a relatively short time.