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This paper presents 3D finite element analysis performed for a composite cylindrical tank made of 6061-aluminum liner overwrapped with carbon fibers subjected to a burst internal pressure of 1610 bars. As the service pressure expected in these tanks is 700 bars, a factor of safety of 2.3 is kept the same for all designs. The optimal design configuration of such high pressure storage tanks includes an inner liner used as a gas permeation barrier, geometrically optimized domes, inlet/outlet valves with minimum stress concentrations, and directionally tailored exterior reinforcement for high strength and stiffness. Filament winding of pressure vessels made of fiber composite materials is the most efficient manufacturing method for such high pressure hydrogen storage tanks. The complexity of the filament winding process in the dome region is characterized by continually changing the fiber orientation angle and the local thickness of the wall.

Mortar weapons systems have existed for more than five hundred years. Though modern tube-launched rounds are far more advanced than the cannon balls used in the 15th century, the parabolic trajectory and inability to steer the object after launch remains the same. Equipping the shell with extending aerodynamic surfaces transforms the unguided round into a maneuverable munition with increased range [1] and precision [2]. The subject of this work is the experimental analysis of transient aerodynamic behavior of a transforming tube-launched unmanned aerial vehicle (UAV) during transition from a ballistic trajectory to winged flight. Data was gathered using a series of wind tunnel experiments to determine the lift, drag, and pitching moment exerted on the prototype in various stages of wing deployment. Flight models of the design were broken down into three configurations: “round”, “transforming”, and “UAV”.

In this paper an approach is presented for the system parameterization and synthesis of a Rand-Cam® Engine configuration based on an axial-cylindrical cam driven mechanism. This engine consists of a stationary axial-cylindrical cam on which axially moving pistons (vanes) sweep around the cam as they are driven by the rotor, providing the volume displacement as the rotor delivers the rotary output torque directly to the shaft. It has been documented that this engine configuration has some unique features that make it particularly suitable for high power to weight ratio applications. The modeling strategy makes use of higher order curve and surface modeling techniques and object modeling approaches based on profile extruding, blending operations and constructive solid geometry. Some of the resulting models are further used for finite element engineering analysis through a programmatic logic built into the parameterized general model.

Regulated gaseous and particulate emissions were obtained from in-use vehicles, two trucks and two buses, operated on the Transportable Heavy Duty Engine Emissions Testing Laboratory. Presented here is the data on transient emissions from a refuse truck with a Cummins LTA10-260 engine, a GMC tractor with a CAT 3176 engine and two buses with Detroit Diesel 6V-92TA engines (one with a particulate trap and the other without) when tested on different fuels. The reported study on in-use heavy duty vehicles is part of an on-going program aimed at establishing a database on the exhaust emissions from vehicles tested on a chassis dynamometer under conditions that represent the ‘real-world’ situations. The paper also discusses, briefly, the entire testing laboratory. The Transportable Laboratory can be effectively used in testing programs, such as recall, deterioration and emission factors.

In this study a higher-order shear deformable, analytical model is developed to analyze composite shells with parametric modeling capabilities. The material and geometric properties and loading conditions can be varied as parameters which satisfy a set of constraints to allow the designer to achieve a sensible and computationally feasible FE model. The formulation is derived with equal emphasis on all the six strain as well as stress components at a generic point in the shell laminate. Unlike many other available models which violates the equilibrium conditions at lamina interfaces, this model satisfies the equilibrium conditions at the lamina interfaces for a certain class (angle-ply and unidirectional orthotropic) of laminates.

In the case of advanced light weight material applications, the design of such components, in many cases, are based on applied surface tractions These surface loads can be caused by various means. When wind effects are present these tractions can be due to pressure, suction or drag. In the case of underwater applications, hydrostatic pressure and friction caused by moving against water current needs to be considered in the design. These are some of the traction load applications, a design engineer has to deal with in his advanced material applications. In contrast to the conventional materials, the modern structures made of highly directional dependent material properties, respond the applied loads and environment in an unpredicted way, so that, a detail analysis and design is always necessary. Hence in the present study a higher-order shear deformation formulation is developed to calculate the distribution of stresses accurately in angle-ply laminated shells of revolution.

Recent interest in the effect of engine life on vehicle emissions, particularly those from alternately fueled engines, has led to a need to test heavy duty trucks in the field over their lifetime. West Virginia University has constructed two transportable laboratories capable of measuring emissions as a vehicle is driven through a transient test schedule. Although the central business district (CBD) cycle is well accepted for bus testing, no time-based schedule suited to the testing of class 8 trucks with unsynchronized transmissions is available. The Federal Test Procedure for certifying heavy duty engines can be translated with some difficulty into a flat road chassis cycle although original data clearly incorporated unpredictable braking and inclines. Two methods were attempted for this purpose, but only an energy conservation method proved practical.

Concern over atmospheric pollution has led to the development of testing procedures to evaluate the hydrocarbon, carbon dioxide, carbon monoxide and oxides of nitrogen emissions from internal combustion engines. In order to perform emissions testing on vehicles, a chassis dynamometer capable of simulating expected driving conditions must be employed. West Virginia University has developed a Heavy Duty Transportable Emissions Testing Laboratory to perform chassis testing on trucks and buses. Emissions from the vehicle are monitored and recorded over the duration of a testing schedule. Usually the vehicle emissions from the whole test are reported as mass of emissions per unit distance driven. However, there is interest in relating the instantaneous emissions to the immediate conditions at specific points in the test, and in determining the emissions for discrete segments of the test (modal analysis).

Emissions from light duty vehicles have traditionally been measured using a chassis dynamometer, while heavy duty testing has been based on engine dynamometers. However, the need for in-use vehicle emissions data has led to the development of two transportable heavy duty chassis dynamometers capable of testing buses and heavy trucks. A test cycle has been developed for Class 8 trucks, which typically have unsyncronized transmissions. This test cycle has five peaks, each consisting of an acceleration, cruise period, and deceleration, with speeds and acceleration requirements that can be met by virtually all vehicles in common service. Termed the “WVU 5 peak truck test”, this 8 km (5 mile) cycle has been used to evaluate the emissions from diesel and ethanol powered over-the-road tractors and from diesel and ethanol powered snow plows, all with Detroit Diesel 6V92 engines.

The need to assess the effect of exhaust gas emissions from heavy duty vehicles (buses and trucks) on emission inventories is urgent. Exhaust gas emissions measured during the fuel economy measurement test procedures that are used in different countries sometimes do not represent the in-use vehicle emissions. Since both local and imported vehicles are running on the roads, it is thought that studying the testing cycles of the major vehicle manufacturer countries is worthy. Standard vehicle testing cycles on chassis dynamometer from the United States, Canada, European Community Market, and Japan1 are considered in this study. Each of the tested cycles is categorized as either actual or synthesized cycle and its representativness of the observed driving patterns is investigated. A total of fourteen parameters are chosen to characterize any given driving cycle and the cycles under investigation were compared using these parameters.

A novel engine concept, currently under study, addresses many of the problems commonly associated with conventional internal combustion engines. In its simplest form the novel engine consists of a single crankshaft operating both a piston compressor and a piston expander which are connected by a continuous flame combustion chamber. One might regard this as a Brayton piston engine which is similar to a previous engine investigated by Warren. Also, due to the use of piston cylinders as the compression and expansion devices, this engine varies little mechanically from current engine technology thus allowing for easy implementation. The main improvement from conventional engine design is that the expansion cylinder can have a larger displacement than that of the compression cylinder. This allows more power to be extracted by lowering the loss due to blowdown and this will increase the thermal efficiency.

Growing concern over ground-level ozone and its role in smog formation has resulted in extensive investigation into identifying ozone sources. Motor vehicle exhaust, specifically oxides of nitrogen and hydrocarbons, have been identified as major ozone precursors in urban areas. Past research has concentrated on assessing the impact of emissions from gasoline fueled light duty vehicles. However, little work has been done on identifying ozone precursors from medium and heavy duty diesel fueled vehicles. This paper presents the results of testing performed on a Navistar T 444E 190 horsepower diesel engine which is certified as a light/heavy-duty emissions classification and is used in medium duty trucks up to 11,800 kg (26,000 lb) GVW. Regulated emissions and speciated hydrocarbon emissions were collected using a filter, bag and Tenax adsorption cartridges for both steady state and transient engine operation.

A mathematical model has been developed to transfer Chassis Dynamometer (CD) test cycles for heavy duty vehicles to the equivalent Engine Dynamometer (ED) test cycles. The model assumed a generalized drivetrain layout, and a variable drive line efficiency. An interactive computer code was written to represent the mathematical model for different drivetrain systems. Several CD test cycles were used to obtain equivalent ED test cycles for a sample based upon an urban bus equipped with an automatic transmission. Results showed the possibility of simulating CD test cycles with equivalent ED test cycles for heavy-duty urban buses under certain assumptions.

Crashworthiness is a measure of a vehicle's structural integrity during mechanical impact and of its ability to absorb energy and provide occupant protection in crash situations. Finite element modeling has been successfully used to simulate collision events; the present work uses these techniques to simulate the side impact of a mid-size car in order to investigate the crash characteristics of a 45 km/hr impact. Five different analyses were conducted on orthogonal and oblique impacts under varying conditions. The numerical results from the first analysis were compared with published experimental crash results, showing favorable comparisons for this numerical model prediction.

It has been proposed that an automated remote color inspection of automobile body panels is possible with a reasonably precise color measurement. This paper outlines a test of a new 3D color measurement technology as applied to this task and presents the results of the first test. A camera is set up several feet away from a car body; a 3D orientation measuring system takes both 3D and color data from the car. The raw data is presented as a set of 3D graphs; the geometry-corrected data is also provided. Statistical analysis is presented to indicate system precision.

The hydrogen economy envisioned in the future requires safe and efficient means of storing hydrogen fuel for either use on-board vehicles, delivery on mobile transportation systems or high-volume storage in stationary systems. The main emphasis of this work is placed on the high -pressure storing of gaseous hydrogen on-board vehicles. As a result of its very low density, hydrogen gas has to be stored under very high pressure, ranging from 350 to 700 bars for current systems, in order to achieve practical levels of energy density in terms of the amount of energy that can be stored in a tank of a given volume. This paper presents 3D finite element analysis performed for a composite cylindrical tank made of 6061-aluminum liner overwrapped with carbon fibers subjected to a burst internal pressure of 1610 bars. As the service pressure expected in these tanks is 700 bars, a factor of safety of 2.3 is kept the same for all designs.

The Stiller-Smith Engine employs a non-standard gear train and as such requires a closer examination of the design and sizing of the gears. To accomplish this the motion of the Stiller-Smith gear train -will be compared to more familiar arrangements. The results of a kinematic and dynamic analysis will introduce the irregular forces that the gears are subjected to. The “floating” or “trammel” gear will be examined more closely, first stochastically and then with finite element analysis. This will pinpoint high stress concentrations on the gear and where they occur during the engine cycle, The configuration considered will be one with: an output shaft, negligible idler gear forces, and floating gear pins that are part of the connecting rods rather than the floating gear. Various loading techniques will be discussed with possible ramifications of each.

The objective of this project, which is supported by the U.S. Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL), is to provide a comprehensive comparison of heavy-duty trucks operating on alternative fuels and diesel fuel. Data collection from up to eight sites is planned. Currently, the project has four sites: Raley's in Sacramento, CA (Kenworth, Cummins L10-300G, liquefied natural gas - LNG); Pima Gro Systems, Inc. in Fontana, CA (White/GMC, Caterpillar 3176B Dual-Fuel, compressed natural gas - CNG); Waste Management in Washington, PA (Mack, Mack E7G, LNG); and United Parcel Service in Hartford, CT (Freightliner Custom Chassis, Cummins B5.9G, CNG). This paper summarizes current data collection and evaluation results from this project.

Diesel soot interacts with the engine oil and leads to wear of engine parts. Engine oil additives play a crucial role in preventing wear by forming the anti-wear film between the wearing surfaces. The current study was aimed at investigating the interactions between engine soot and oil properties in order to develop high performance oils for diesel engines equipped with exhaust gas re-circulation (EGR). The effect of soot contaminated oil on wear of engine components was examined using a statistically designed experiment. To quantitatively analyze and simulate the extent of wear a three-body wear machine was designed and developed. The qualitative wear analysis was performed by examining the wear scars on an AISI 52100 stainless steel ball worn in the presence of oil test samples on a ball-on-flat disc setup. The three oil properties studied were base stock, dispersant level and zinc dithiophosphate level.

Speed-time and video data were logged for tractor-trailers performing local deliveries in Akron, OH. and Richmond, VA. in order to develop an emissions test schedule that represented real truck use. The data bank developed using these logging techniques was used to create a Yard cycle, a Freeway cycle and a City-Suburban cycle by the concatenation of microtrips. The City-Suburban driving cycle was converted to a driving route, in which the truck under test would perform at maximum acceleration during certain portions of the test schedule. This new route was used to characterize the emissions of a 1982 Ford tractor with a Cummins 14 liter, 350 hp engine and a 1998 International tractor with a Cummins 14 liter, 435 hp engine. Emissions levels were found to be repeatable with one driver and the driver-to-driver variation of NOx was under 4%, although the driver-to-driver variations of CO and PM were higher.