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Current U.S. Army ground vehicles predominately use commercial off-the-shelf or modified commercial diesel engines as the prime mover. Unique military engines are typically utilized when commercial products do not meet the mobility requirements of the particular ground vehicle in question. In either case, such engines traditionally have been calibrated using North American diesel fuel (DF-2) and Jet Propellant 8 (JP-8) compatibility wasn't given much consideration since any associated power loss due to the lower volumetric energy density was not an issue for most applications at then targeted climatic conditions. Furthermore, since the genesis of the ‘one fuel forward policy’ of using JP-8 as the single battlefield fuel there has been limited experience to truly assess fuel effects on diesel engine combustion systems until this decade.

The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Gasoline engine downsizing is already established as a technology for reducing vehicle CO2 emissions. Further benefits are possible through more aggressive downsizing, however, the tradeoff between the CO2 reduction achieved and vehicle drivability limits the level of engine downsizing currently adopted by vehicle manufacturers. This paper will present the latest results achieved from a very heavily downsized engine, and resulting demonstrator vehicle, featuring eSupercharging in combination with a conventional turbocharger. The original 1.2 litre, 3-cylinder, MAHLE downsizing engine has been re-configured to enable a specific power output in excess of 160 kW/litre. Of key importance is a cost effective, efficient and flexible boosting system.

The ISO TC22/SWG2 - Brake Lining Committee established a task force to determine and analyze root causes for variability during dynamometer brake performance testing. SAE paper 2010-01-1697 “Brake Dynamometer Test Variability - Analysis of Root Causes” [1] presents the findings from the phases 1 and 2 of the “Test Variability Project.” The task force was created to address the issue of test variability and to establish possible ways to improve test-to-test and lab-to-lab correlation. This paper presents the findings from phase 3 of this effort-description of factors influencing test variability based on DOE study. This phase concentrated on both qualitative and quantitative description of the factors influencing friction coefficient measurements during dynamometer testing.

Typical design challenges for Unmanned Aerial Vehicles (UAVs) require low aerodynamic drag and structural weight. Both of these requirements imply that these aircraft are considerably more flexible than conventional aircraft and their stability analyses are more complex since they require models unifying rigid body and elastic dynamics. This paper aims to built such a model for a generic UAV. The model is then used to address stability in terms of divergence and flutter.

Development of reliable magnesium (Mg) to steel joining methods is one of the critical issues in broader applications of Mg in automotive body construction. Ultrasonic spot welding (USW) has been demonstrated successfully to join Mg to steel and to achieve strong joints. In this study, corrosion test of ultrasonic spot welds between 1.6 mm thick Mg AZ31B-H24 and 0.8 mm thick galvanized mild steel, without and with adhesive, was conducted. Adhesive used was a one-component, heat-cured epoxy material, and was applied between overlapped sheets before USW. Corrosion test was conducted with an automotive cyclic corrosion test, which includes cyclic exposures of dipping in the 0.5% sodium chloride (NaCl) bath, a constant humidity environment, and a drying period. Lap shear strength of the joints decreased with the cycles of corrosion exposure. Good joint strengths were retained at the end of 30-cycle test.

It is well known that the drilling industry is a diverse industry with huge power needs for drilling deep wells. This paper discusses the drilling industry in general and the future need for HT power electronics to enable such activities as tractor drive drilling of deep horizontal wells. The discussion is geared at applications for drilling within the earth at ambient temperatures of 150°C and above.

The results of an experimental study in a DI Diesel engine are presented which shows that partial premixing, using direct diesel fumigation of the inlet air, achieved a reduction in the ignition delay, the magnitude of high frequency rapid pressure fluctuations, the maximum rate of pressure rise and the amplitude of the rate of the high frequency pressure oscillations. Two methods of diesel fumigation were investigated. The difference between these two methods was the degree of premixing of diesel fuel with the inlet air. The first technique used a fine (5 micron) diesel spray onto a glow plug and the second technique used prevaporised diesel. A Perkins 4-236 engine was run both with and without fumigation at two different steady state speeds roughly covering both city and highway running conditions.

Recreational marine engine operation effects water quality as well as air quality. Significant quantities of hydrocarbons are discharged into the rivers, lakes, and estuaries used as recreational boating waters. In order to investigate the impact of recreational marine engine operation on water quality, a MerCruiser 3.0LX four-cylinder four-stroke inboard engine and a Mercury 650 two-cylinder two-stroke outboard engine were tested using EPA required certification procedures. Both engines were tested with exhaust gas/cooling water mixing (scrubbing) in the exhaust stream using both freshwater and saltwater. Additionally, the inboard engine was tested without exhaust scrubbing. Gaseous emissions (HC, NOX, CO, and CO2) from the engines were continuously measured using a constant volume sampling system. Both exhaust gas and cooling water samples were collected and speciated for hydrocarbon species present.

A brief overview of the history and scope of the SAE Oil Labeling Assessment Program is presented. Then, the results of analyses on 893 samples of engine oil purchased in the retail market over the first three years of the program, are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API “C” category designation. Additionally, 43 engine oil samples found to be questionably labeled, were repurchased and analyzed; these results are included.

The automotive industry is pursuing significant cost competitive efforts to reduce vehicle weight while maintaining or improving durability and impact performance. One such effort for the body shell structure is the utilization of advanced and ultra high strength steels (AHSS and UHSS) using the existing automotive manufacturing infrastructure. Common AHSS and UHSS steels include Dual Phase (DP), Transformation Induced Plasticity (TRIP), Partial Martensitic (PM) and others. The use of these multiphase high strength steels for impact dependent components has resulted in the need for further material characterization in order to better predict impact performance and guide new material development. This paper addresses the material properties and microstructural influences on impact behavior of advanced and ultra high strength steels through the use of laboratory tests and component level testing.

Laser transmission welding is a relatively new technique for joining thermoplastic components in the automotive industry. Laser energy is passed through a laser-transparent part and dissipated as heat in a laser-absorbent component. There is currently no standardized test to assess the strength of laser transmission welds made using thermoplastic materials. A properly-designed test allows the weld strength of the joint to be measured accurately and rapidly. This paper reports on a technique for measuring overlap shear strength. This study compares two weld orientations (weld line parallel and perpendicular to assembly loading) using polycarbonate, polypropylene, polyamide 6, polyamide 6 reinforced with 30% glass fibres and polyamide mXD6 reinforced with 50% glass fibres. Assemblies were made using a range of laser powers. In order to simulate industrial conditions, artificial gaps were also introduced between the transparent and absorbent parts.

Simple component models are advantageous when simulating vehicle AC systems so that overall model complexity and computation time can be minimized. These models must be robust enough to avoid instability in the iteration method used for determining the AC system operating or “balance” point. Simplicity and stability are especially important when the AC system model is coupled with a vehicle interior model for studies of transient performance because these are more computationally intensive. This paper presents a semi-empirical modeling method for compressors based on dimensionless parameters. Application to some sample compressor data is illustrated. The model equations are simple to employ and will not introduce significant stability problems when used as part of a system simulation.

The effect of hydroforming on the mechanical properties and dynamic crush behaviors of tapered aluminum 6063-T4 tubes with octagonal cross section are investigated by experiments. First, the thickness profile of the hydroformed tube is measured by non-destructive examination technique using ultrasonic thickness gauge. The effect of hydroforming on the mechanical properties of the tube is investigated by quasi-static tensile tests of specimens prepared from different regions of the tube based on the thickness profile. The effect of hydroforming on the dynamic crush behaviors of the tube is investigated by axial crush tests under dynamic loads. Specimens and tubes are tested in two different heat treatment conditions: hydroformed-T4 (as-received) and T6. The results of the quasi-static tensile tests for the specimens in hydroformed-T4 condition show different amounts of work hardening depending on the regions, which the specimens are prepared from.

The implementations of the Tier 2 and LEVII emission levels require fast catalyst light-off and fast closed loop control through high-speed engine management. The paper describes the development of innovative catalyst designs. During the development thermal and mechanical boundary conditions were collected and component tests conducted on test rigs to identify the emission and durability performance. The products were evaluated on a Super Imposed Test Setup (SIT) where thermal and mechanical loads are applied to the test piece simultanously and results are compared to accelerated vehicle power train endurance runs. The newly developed light-off catalyst with Perforated Foil Technology (PE) showed superior emission light-off characteristic and robustness.

An experiment was performed with a 1.3L catalytic converter design containing a front and rear catalyst each having a volume of 0.65 liters. This investigation varied the front catalyst parameters to study the effects of 1) substrate diameter, 2) substrate cell density, 3) Pd loading and 4) Rh loading on the FTP emissions on three different vehicles. Engine displacement varied from 2.4L to 4.7L. Eight different converters were built defined by a Taguchi L-8 array. Cold flow converter restriction results show the tradeoff in converter restriction between substrate cell density and substrate diameter. Vehicle FTP emissions show how the three vehicles are sensitive to the four parameters investigated. Platinum Group Metals (PGM) prices and Federal Test Procedure (FTP) emissions were used to define the emission value between the substrate properties of diameter and cell density to palladium (Pd) and rhodium (Rh) concentrations.

This paper presents the results of CFD study on sunroof buffeting suppression using a dividing bar. The role of a dividing bar in side window buffeting case was illustrated in a previous study [8]. For the baseline model of the selected vehicle in this study, a very high level of sunroof buffeting, 133dB, has been found. The CFD simulation shows that the buffeting noise can be significantly reduced if a dividing bar is installed at the sunroof. A further optimization study on the dividing bar demonstrates that the peak buffeting level can be reduced to 123dB for the selected vehicle if the dividing bar is installed at its optimal location, 65% of the total length from the front edge of the sunroof. The peak buffeting level can be further reduced to 100dB if the dividing bar takes its optimal width 80mm, 15% of the total length of the sunroof for this vehicle, while staying at its optimal location.

More than 200 tensile-shear resistance spot welded specimens were produced and tested to analyze the effect of spot weld spacing, weld size, sheet thickness, and adhesive on the ultimate strength of joints made from a mild hot dip galvannealed steel and an unexposed quality hot dip galvannealed 590 MPa minimum tensile strength dual phase steel (DP590). The geometric layout parameters were analyzed by a design of experiment (DOE) approach. The analysis showed that weld size is a primary factor affecting the strength of the joints for a given material. It was also determined that structural adhesive created a large relative strengthening for joints made from the mild steel. Interactions of the geometrical factors are also presented.

The relationship between the response (output) and the input factors on a system or process is always needed. This relationship can be used to optimize the response. The Central Composite Design (CCD) is the most commonly used in response surface study. The Uniform Design (UD) can have a small number of experiments to explore relationship between the response and the factors. In this paper, the physics-based simulation model of a “Heater fan motor” will be used to investigate the accuracy of the response (angular velocity) by the prediction models from CCD and UD.

The project objective was to investigate the ultrafine solid particle emissions of the prevalent traffic, by performing field measurements at an urban traffic artery in Zurich/Switzerland. Subsequently, various scenarios were postulated to assess the potential of the diesel particle filters (DPF) to improve curbside air quality. Soot aerosols are known to be carcinogenic [1]. If all heavy-duty diesel vehicles were equipped with DPFs, then the number of particles emitted from the entire vehicle fleet could be reduced by 75 to 80%. For PM10, the curtailment scope is considerably lower, around 20%, because more than half of those emissions are not from the exhaust and therefore would not be filtered.