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A program has been completed to evaluate ultra-low sulfur diesel fuels and passive diesel particulate filters (DPFs) in truck and bus fleets operating in southern California. The fuels, ECD and ECD-1, are produced by ARCO (a BP Company) and have less than 15 ppm sulfur content. Vehicles were retrofitted with two types of catalyzed DPFs, and operated on ultra-low sulfur diesel fuel for over one year. Exhaust emissions, fuel economy and operating cost data were collected for the test vehicles, and compared with baseline control vehicles. Regulated emissions are presented from two rounds of tests. The first round emissions tests were conducted shortly after the vehicles were retrofitted with the DPFs. The second round emissions tests were conducted following approximately one year of operation. Several of the vehicles retrofitted with DPFs accumulated well over 100,000 miles of operation between test rounds.

Unmanned Aerial Vehicles (UAV) require simple and reliable engines of high power to weight ratio. Wankel and two stroke engines offer many advantages over four stroke engines. A two stroke engines featuring crank case scavenging, precise oiling, direct injection and jet ignition is analyzed here by using CAD, CFD and CAE tools. Results of simulations of engine performances are shown in details. The CFD analysis is used to study fuel injection, mixing and combustion. The CAE model then returns the engine performances over the full range of loads and speeds with the combustion parameters given as an input. The use of asymmetric rather than symmetric port timing and supercharging scavenging is finally suggested as the best avenue to further improve power density and fuel conversion efficiency.

This paper presents on-going finite element modeling efforts of friction stir spot welding (FSSW) process using Abaqus/Explicit as a finite element solver. Three-dimensional coupled thermal-stress model was used to calculate thermo-mechanical response of FSSW process. Adaptive meshing and advection schemes, which makes it possible to maintain mesh quality under large deformations, is utilized to simulate the material flow and temperature distribution in FSSW process. The predicted overall deformation shape of the weld joint resembles that experimentally observed. Temperature and stress graphs in the radial direction as well as temperature-deformation distribution plots are presented.

For adapting the demands of the rapid changing and enhancing the competing capability of enterprise in the international market, various modern manufacturing systems have been put forward, which are aimed at various specifications, perfect performance and high quality, low production cost and short manufacturing cycle of products, virtual manufacturing system ( VMS) has been emerged as the times require, which is effective technology to meet the challenge of 21 century's manufacturing industries. Based on analyzing modern manufacturing systems, according to the characteristics and requirement of VMS, in this paper, the architecture, the key technologies and the implement way of VMS were explored, and development environment for VMS was put forward, which is a powerful tool for building VMS.

The high demand for traditional air traffic as well as increased use of unmanned aerial systems (UAS) has resulted in researchers examining alternative technologies which would result in safer, more reliable, and better performing aircraft. Active methods of aerodynamic flow control may be the most promising approach to this problem. Research in the area of aerodynamic control is transitioning from traditional mechanical flow control devices to, among other methods, plasma actuators. Plasma actuators offer an inexpensive and energy efficient method of flow control. Dielectric Barrier Discharge (DBD), one of the most widely studied forms of plasma actuation, employs an electrohydrodynamic (EHD) device which uses dominant electric fields for actuation. Unlike traditional flow control methods, a DBD device operates without moving components or mass injection methods.

Yard hostlers are tractors (switchers) used to move containers at ports and storage facilities. While many speed-time driving cycles for assessing emissions and performance from heavy-duty vehicles exist, a driving cycle representative of yard hostler activity at Port of Long Beach, CA was not available. Activity data were collected from in-use yard hostlers as they performed ship loading/unloading, rail loading/unloading and other yard routines, primarily moving containers on trailers or carts. The activity data were then used to develop four speed-time driving cycles with durations of 1200 seconds, representing light and heavy ship activities and light and heavy load rail activities. These cycles were constructed using actual speed-time data collected during activity logging and the cycles created were statistically comparable to each subset of activity data.

This paper examines the energy pathways of a 29cc air-cooled two-stroke engine operating on natural gas with different exhaust geometries. The engine was operated at wide-open-throttle at a constant speed of 5400 RPM with ignition adjusted to yield maximum brake torque while the fueling was adjusted to examine both rich and lean combustion. The exhaust configurations examined included an off-the-shelf (OTS) model and two other custom models designed on Helmholtz resonance theory. The custom designs included both single and multi-cone features. Out of the three exhaust systems tested, the model with maximum trapping efficiency showed a higher overall efficiency due to lower fuel short-circuiting and heat transfer. The heat transfer rate was shown to be 10% lower on the new designs relative to OTS model.

Tube Launched-Unmanned Air Vehicles (TL-UAV) are munitions that alter their trajectories during flight to enhance the capabilities by possibly extending range, increasing loiter time through gliding, and/or having guided targeting capabilities. Traditional munition systems, specifically the tube-launched mortar rounds, are not guided. Performance of these "dumb" munitions could be enhanced by updating to TL-UAV and still utilize existing launch platforms with standard propellant detonation firing methods. The ability to actively control the flight path and extend range of a TL-UAV requires multiple onboard systems which need to be identified, integrated, assembled, and tested to meet cooperative function requirements. The main systems, for a mortar-based TL-UAV being developed at West Virginia University (WVU), are considered to be a central hub to process information, aerodynamic control devices, flight sensors, a video camera system, power management, and a wireless transceiver.

Performance of a natural gas two-stroke engine incorporated in a 1-kW free-piston oscillating Linear Engine Alternator (LEA) - a household electricity generator - was investigated under different resonant frequencies for pre-design phase purposes. To increase the robustness, power density, and thermal efficiencies, the crank mechanism in free-piston LEA is omitted and all moving parts of the generator operate at a fixed resonant frequency. Flexure springs are the main source of the LEA’s stiffness and the mass-spring dynamics dominates the engine’s speed. The trade-off between the engine’s performance, mass-spring system limits, and power and efficiency targets versus the LEA speed is very crucial and demands a careful investigation specifically at the concept design stages to find the optimum design parameters and operating conditions. CFD modeling was performed to analyze the effects of resonant frequency on the engine’s gas exchange behavior.

The temporary deactivation of the selective catalytic reduction (SCR) device due to malfunction requires the engine control to engage multiple engine-out calibrations. Further, it is expected that emitted particles will be different in composition, size and morphology when an engine, which meets the 2010 particulate matter (PM) gravimetric limits, is programmed with multiple maps. This study investigated the correlation between SCR-out/engine-out PM emissions from an 11-liter Volvo engine. Measurement of PM concentrations and size distributions were conducted under steady state and transient cycles. Ion Chromatograph analysis on gravimetric filters at the SCR-out has revealed the presence of sulfates. Two different PM size-distributions were generated over a single engine test mode in the accumulation mode region with the aid of a design of experiment (DOE) tool. The SCR-out PM size distributions were found to correlate with the two engine-out distributions.

As unmanned aerial vehicle applications continue their rise in popularity in the public and private sectors, there is an increasing demand in many cases for smaller, more efficient low speed unmanned aerial vehicles (UAVs). Although the primary drivers for the continued performance improvement of smaller UAV platforms tend to be in the areas of electronics miniaturization and improved energy storage, aerodynamics, particularly in the low Reynolds number regime, still have a significant role in the overall performance enhancement of small UAVs. This paper focuses on the study of the nearfield aerodynamic effects of a low-power active flow enhancement technique known as dielectric barrier discharge (DBD) in very low speed/low Reynolds number flows most closely associated with small and micro unmanned aerial vehicles.

Dual primary full-flow dilution tunnels represent an integral part of a heavy-duty transportable emissions measurement laboratory designed and constructed to comply with US Code of Federal Regulations (CFR) 40 Part 1065 requirements. Few data exist to characterize the evolution of particulate matter (PM) in full scale dilution tunnels, particularly at very low PM mass levels. Size distributions of ultra-fine particles in diesel exhaust from a naturally aspirated, 2.4 liter, 40 kW ISUZU C240 diesel engine equipped with a diesel particulate filter (DPF) were studied in one set of standard primary and secondary dilution tunnels with varied dilution ratios. Particle size distribution data, during steady-state engine operation, were collected using a Cambustion DMS500 Fast Particulate Spectrometer. Measurements were made at four positions that spanned the tunnel cross section after the mixing orifice plate for the primary dilution tunnel and at the outlet of the secondary dilution tunnel.

Air cargo containers are used to load freight on various types of aircrafts to expedite their handling. Fuel cost is the largest contributor to the total cost of ownership of an air cargo container. Therefore, a better fuel economy could be achieved by reducing the weight of such containers. This paper aims at developing innovative, lightweight design concepts for air cargo containers that would allow for weight reduction in the air cargo transportation industry. For this purpose, innovative design and assembly concepts of lightweight design configurations of air cargo containers have been developed through the applications of lightweight composites. A scaled model prototype of a typical air cargo container was built to assess the technical feasibility and economic viability of creating such a container from fiber-reinforced polymer (FRP) composite materials. The paper is the authoritative source for the abstract.

Overexertion injuries comprise the largest category of nonfatal injuries among construction workers. These injuries typically occur when the biomechanical stresses associated with tasks such as lifting, carrying, pushing, etc., exceed the worker’s strength capacity. Two studies were conducted to measure the whole-body isometric strength capability of 56 construction workers. The first study examined the effect of four typical postures (2 symmetric lifts and 2 asymmetric lifts) associated with scaffold end frame disassembly. The effect of posture on isometric strength capability was significant; the strength capability ranged from 366 N to 676 N. The second study evaluated the effect of hand separation distance (46 cm, 86.4 cm, and 116.8 cm) and vertical hand placement (knuckle, elbow, and acromial heights) on isometric force during symmetric lifting postures. The interaction effect of hand separation distance - vertical hand placement on isometric strength capability was significant.

Significant efforts have been made in the research of Pulsed Detonation Engines (PDEs) to increase the reliability and longevity of detonation based propulsion systems for use in manned aircraft. However, the efficiency, durability, and low mechanical complexity of PDEs opens up potential for use in disposable unmanned-vehicles. This paper details the steps taken for producing a miniaturized pulse detonation engine at West Virginia University (WVU) to investigate the numerically generated constraining dimensions for Deflagration to Detonation Transition (DDT) cited in this paper. Initial dimensions for the WVU PDE Demonstrator were calculated using fuel specific DDT spatial properties featured in the work of Dr. Phillip Koshy Panicker, of The University of Texas at Arlington. The WVU demonstrator was powered using oxygen and acetylene mixed in stoichiometric proportions.

There is an ever growing need in the aircraft industry to increase the performance of a flight vehicle. To enhance performance of the flight vehicle one active area of research effort has been focused on the control of the boundary layer by both active and passive means. An effective flow control mechanism can improve the performance of a flight vehicle by eliminating boundary layer separation at the leading edge (as long as the energy required to drive the mechanism is not greater than the savings). In this paper the effectiveness of a novel active flow control technique known as dynamic roughness (DR) to eliminate flow separation in a stalled NACA 0012 wing has been explored. As opposed to static roughness, dynamic roughness utilizes small time-dependent deforming elements or humps with amplitudes that are on the order of the local boundary layer height to energize the local boundary layer. DR is primarily characterized by the maximum amplitude and operating frequency.

Since the quality activities is through out the product whole life-cycle, the quality management should be a integrated quality system, facing the product life-cycle. In CIMS(Computer Integrated Manufacturing System), with the assistance of computer and its relative technologies, IQS(Integrated Quality System) can integrate the quality management technique cells into an organic whole, then the quality management will be more coherent and efficient. In this paper the concept, features, components and functions of IQS are been discussed and the key technologies are pointed out.

The objective of this paper is to devise innovative lightweight design concepts for heavy vehicle structures. A 1 to 4 prototype of a trailer was built to assess the feasibility of use of polymer composites and to have first hand experience with possible bonding methods to join the design parts. In the current trailer configurations, floor assembly constitutes 70% of the overall weight. The results indicated that sandwich technology with a lightweight core that adds flexural stiffness to the overall design provides a solution to decrease the weight of heavy vehicle systems.

Process planning, whether generative or variant, can be used effectively as through the incorporation of computer aided tools that enhance the evaluator impact of the dialogue between the design and manufacturing functions. Expert systems and algorithms are inherently incorporated into the software tools used herein. This paper examines the materials related implications that influence design for manufacturing issues. Generative process planning software tools are utilized to analyze the sensitivity of the effectiveness of the process plans with respect to changing attributes of material properties. The shift that occurs with respect to cost and production rates of process plans with respect to variations in specific material properties are explored. The research will be analyzing the effect of changes in material properties with respect to the design of a specific product that is prismatic and is produced exclusively by machining processes.

A Hybrid Projectile (HP) is a tube launched munition that transforms into a gliding UAV, and is currently being researched at West Virginia University. In order to properly transform, the moment of transformation needs to be controlled. A simple timer was first envisioned to control transformation point for maximum distance. The distance travelled or range of an HP can directly be modified by varying the launch angle. In addition, an internal timer would need to be reprogrammed for any distance less than maximum range due to the nominal time to deployment varying with launch angle. A method was sought for automatic wing deployment that would not require reprogramming the round. A body angle estimation system was used to estimate the pitch of the HP relative to the Earth to determine when the HP is properly oriented for the designed glide slope angle. It also filters out noise from an inertial measurement unit (IMU).