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Journal Article

Trends in Performance Characteristics of Modern Automobile SI and Diesel Engines

2009-06-15
2009-01-1892
A prior study (Chon and Heywood, [1]) examined how the design and performance of spark-ignition engines evolved in the United States during the 1980s and 1990s. This paper carries out a similar analysis of trends in basic engine design and performance characteristics over the past decade. Available databases on engine specifications in the U.S., Europe, and Japan were used as the sources of information. Parameters analyzed were maximum torque, power, and speed; number of cylinders and engine configuration, cylinder displacement, bore, stroke, compression ratio; valvetrain configuration, number of valves and their control; port or direct fuel injection; naturally-aspirated or turbocharged engine concepts; spark-ignition and diesel engines. Design features are correlated with these engine’s performance parameters, normalized by engine and cylinder displacement.
Journal Article

Residual Stress Analysis of Punched Holes in 6013 Aluminum Alloy Commercial Vehicle Side Rails

2010-10-05
2010-01-1909
Compliance with tighter emission regulations has increased the proportion of parasitic weight in commercial vehicles. In turn, the amount of payload must be reduced to comply with transportation weight requirements. A re-design of commercial vehicle components is necessary to decrease the vehicle weight and improve payload capacity. Side rails have traditionally been manufactured from high strength steels, but significant weight reductions can be achieved by substituting steel side rails with 6013 high strength aluminum alloy side rails. Material and stress analyses are presented in this paper in order to understand the effect of manufacturing process on the material's mechanical behavior. Metallographic and tensile test experiments for the 6013-T4 alloy were performed in preparation for residual stress measurements of a punching operation. Punched holes are critical to the function of the side rail and can lead to high stress levels and cracking.
Journal Article

Analysis of Ride Vibration Environment of Soil Compactors

2010-10-05
2010-01-2022
The ride dynamics of typical North-American soil compactors were investigated via analytical and experimental methods. A 12-degrees-of-freedom in-plane ride dynamic model of a single-drum compactor was formulated through integrations of the models of various components such as driver seat, cabin, roller drum and drum isolators, chassis and the tires. The analytical model was formulated for the transit mode of operation at a constant forward speed on undeformable surfaces with the roller vibrator off. Field measurements were conducted to characterize the ride vibration environments during the transit mode of operation. The measured data revealed significant magnitudes of whole-body vibration of the operator-station along the vertical, lateral, pitch and roll-axes. The model results revealed reasonably good agreements with ranges of the measured vibration data.
Journal Article

Effect of Drying Methods on the Physical and Structural Changes in Oil-Seed Flax Fiber

2010-10-05
2010-01-2024
With the growing environmental concerns, biodegradable materials are gaining more importance. Biocomposites which are made from a combination of biological fiber such as flax and hemp together with plastics are finding a good number of applications in day to day life. Flax has good physical and mechanical properties that can be utilized in areas like construction, biomedical & bioproducts and electronics applications. The quality of fiber depends upon various unit operations used in the processing. Drying is one of the most important unit operations which significantly affect the quality of the fiber. The method of drying for removal of moisture from the fiber significantly affects the drying time and quality. In the present study the raw flax fiber was subjected to drying before and after chemical treatment. The physical properties such as; tensile strength, color and structural changes were measured for raw and chemically treated flax fibers.
Journal Article

Mitigating Heavy Truck Rear-End Crashes with the use of Rear-Lighting Countermeasures

2010-10-05
2010-01-2023
In 2006, there were approximately 23,500 rear-end crashes involving heavy trucks (i.e., gross vehicle weight greater than 4,536 kg). The Enhanced Rear Signaling (ERS) for Heavy Trucks project was developed by the Federal Motor Carrier Safety Administration (FMCSA) to investigate methods to reduce or mitigate those crashes where a heavy truck has been struck from behind by another vehicle. Visual warnings have been shown to be effective, assuming the following driver is looking directly at the warning display or has his/her eyes drawn to it. A visual warning can be placed where it is needed and it can be designed so that its meaning is nearly unambiguous. FMCSA contracted with the Virginia Tech Transportation Institute (VTTI) to investigate potential benefit of additional rear warning-light configurations as rear-end crash countermeasures for heavy trucks.
Journal Article

Impact of Fiber Loading on Injection Molding Processing Parameter and Properties of Biocomposite

2010-10-05
2010-01-2026
The research on using natural fibres as the reinforcement in plastic composites has increased dramatically in the last few years. Flax fibres are renewable resources with low specific mass, reduced energy consumption, and relatively low in cost. These advantages make flax fibres recognized as a potential replacement for glass fibres in composites. Among plastic, polyethylene was concluded to be a suitable material used as matrix in natural fibre reinforced biocomposites. However there are few studies on this area so far. In this paper, the processing method of flax fibre-reinforced polyethylene biocomposites is introduced. Flax fibre polyethylene biocomposite consists of flax fibre as the reinforcing component and high density polyethylene as the matrix. Acrylic acid pre-treatment was applied to flax fibre to improve the bonding between fibre and polyethylene.
Journal Article

A Framework for Developing an EPS Health Management System

2010-11-02
2010-01-1725
This paper describes a framework for developing an Integrated Electrical Power System (EPS) Health Management System. The framework is based on the perspective that health management, unlike other capabilities, is not a self-contained, stand-alone system, but is rather an integral part of every aircraft subsystem, system, and the entire platform. Ultimately, the objective is to improve the entire maintenance, logistics and fleet operations support processes. This perspective requires a new mindset when applying systems engineering design principles. The paper provides an overview description of the framework, the potential benefits of the approach and some critical design and implementation issues based on current development efforts.
Journal Article

Direct Injection of High Pressure Gas: Scaling Properties of Pulsed Turbulent Jets

2010-10-25
2010-01-2253
Existing gasoline DI injection equipment has been modified to generate single hole pulsed gas jets. Injection experiments have been performed at combinations of 3 different pressure ratios (2 of which supercritical) respectively 3 different hole geometries (i.e. length to diameter ratios). Injection was into a pressure chamber with optical access. Injection pressures and injector hole geometry were selected to be representative of current and near-future DI natural gas engines. Each injector hole design has been characterized by measuring its discharge coefficient for different Re-levels. Transient jets produced by these injectors have been visualized using planar laser sheet Mie scattering (PLMS). For this the injected gas was seeded with small oil droplets. The corresponding flow field was measured using particle image velocimetry (PIV) laser diagnostics.
Journal Article

Driver Distraction/Overload Research and Engineering: Problems and Solutions

2010-10-19
2010-01-2331
Driver distraction is a topic of considerable interest, with the public debate centering on the use of cell phones and texting while driving. However, the driver distraction/overload issue is really much larger. It concerns specific tasks such as entering destinations on navigation systems, retrieving songs on MP3 players, accessing web pages, checking stocks, editing spreadsheets, and performing other tasks on smart phones, as well as, more generally, using in-vehicle information systems. Five major problems related to distraction/overload research and engineering and their solutions are addressed in this paper.
Journal Article

Digital Maps, Connectivity and Electric Vehicles - Enhancing the EV/PHEV Ownership Experience

2010-10-19
2010-01-2316
Electrification of the automobile is a growing trend and will create both challenges and opportunities for the vehicle manufacturer, road network infrastructure and driver. In addition to innovative fundamental battery and power transfer technologies, electric vehicles will integrate unique driver interfaces, road intelligence, traffic awareness and wireless data communication to provide a complete support system. This networked vehicle will improve efficiency, increase cruising range and contribute to the overall driving enjoyment of an electric or plug-in hybrid-electric vehicle. Through tailored applications created by content and service providers the driver will identify the most efficient travel routes, learn efficient driving behaviors, avoid energy-wasting situations, locate charging stations and have confidence in reaching a destination and returning home.
Journal Article

Ford SYNC and Microsoft Windows Embedded Automotive Make Digital Lifestyle a Reality on the Road

2010-10-19
2010-01-2319
With Ford SYNC, Microsoft Corporation and Ford Motor Company have democratized in-vehicle infotainment systems - delighting consumers and bringing a new kind of agility to the automobile industry. Built on Microsoft Auto (now Windows Embedded Automotive), Ford SYNC is a factory-installed, voice-controlled communications and entertainment system that allows drivers to converge their digital lifestyle with their life on the road. Windows Embedded Automotive is an industry leading technology platform that provides integrated infotainment features and a rich user interface. Car manufacturers and suppliers worldwide can use this software to create differentiated, infotainment in-vehicle systems that are immediately attractive to consumers.
Journal Article

Enabling Safety and Mobility through Connectivity

2010-10-19
2010-01-2318
Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) networks within the Intelligent Transportation System (ITS) lead to safety and mobility improvements in vehicle road traffic. This paper presents case studies that support the realization of the ITS architecture as an evolutionary process, beginning with driver information systems for enhancing feedback to the users, semi-autonomous control systems for improved vehicle system management, and fully autonomous control for improving vehicle cooperation and management. The paper will also demonstrate how the automotive, telecom, and data and service providers are working together to develop new ITS technologies.
Journal Article

ESC Performance of Aftermarket Modified Vehicles: Testing, Simulation, HIL, and the Need for Collaboration

2010-10-19
2010-01-2342
The enactment of FMVSS 126 requires specific safety performance in vehicles 4,536 Kg (10,000 pounds) or less using an Electronic Stability Control (ESC) system as standard equipment by 2011. Further, in 2012, the regulation requires vehicles that have undergone aftermarket modification to remain in compliance with the performance standard. This paper describes: • a brief overview of the standard and its implications • the collaborative approach used in the first successful approach in meeting that requirement by a lift kit manufacturer o a Hardware In the Loop (HIL) test alternative for establishing a reasonable expectation for a vehicle to demonstrate compliance after modification. • Collaborative challenges overcome: o aftermarket manufacturers seeking information sharing with OEMs and Tier One suppliers: o respecting the intellectual property of OEMs and Tier One suppliers o maintaining the integrity between tool competitors and their customers in cross-collaborative efforts
Journal Article

Improving Driver Safety through Naturalistic Data Collection and Analysis Methods

2010-10-19
2010-01-2333
The design of a safe transportation system requires numerous design decisions that should be based on data acquired by rigorous scientific method. Naturalistic data collection and analysis methods are a relatively new addition to the engineer's toolbox. The naturalistic method is based on unobtrusively monitoring driver and vehicle performance under normal, everyday, driving conditions; generally for extended collection periods. The method generates a wealth of data that is particularly well-suited for identifying the underlying causes of safety deficiencies. Furthermore, the method also provides robust data for the design and evaluation of safety enhancement systems through field studies. Recently the instrumentation required to do this type of study has become much more cost effective allowing larger numbers of vehicles to be instrumented at a fraction of the cost. This paper will first provide an overview of the naturalistic method including comparisons to other available methods.
Journal Article

Mechanical Performance of Circular AA6061-T6 Extrusions Under Axial Cutting Deformation

2011-04-12
2011-01-0022
Dynamic and quasi-static axial cutting of circular AA6061-T6 extrusions with variable instantaneous wall thickness in the axial direction was completed to investigate the capability of controlling the load/displacement responses of the extrusions. Circular specimens considered for this research had an original nominal wall thickness of 3.175 mm, an external diameter of 50.8 mm, and a tube length of 300 mm. Variations of the wall thickness were completed by material removal of the extrusions using a CNC machine. Specially designed cutters having a block height of 20 mm, a blade tip width of 1.0 mm and a blade shoulder width of 3.0 mm were employed to generate the axial cutting deformation mode. Either one or two cutters were selected to initiate a single or dual cutting deformation. A curved deflector with a profile radius of 50.8 mm was used to flare the cut petalled sidewalk and facilitate the cutting system.
Journal Article

Loading Path Dependence of Forming Limit Diagram of a TRIP800 Steel

2011-04-12
2011-01-0019
In this paper, the microstructure-based finite element modeling method is used in investigating the loading path dependence of formability of transformation induced plasticity (TRIP) steels. For this purpose, the effects of different loading path on the forming limit diagrams (FLD) of TRIP steels are qualitatively examined using the representative volume element (RVE) of a commercial TRIP800 steel. First, the modeling method was introduced, where a combined isotropic/kinematic hardening rule is adopted for the constituent phases in order to correctly describe the cyclic deformation behaviors of TRIP steels during the forming process with combined loading paths which may include the unloading between the two consecutive loadings. Material parameters for the constituent phases remained the same as those in the authors' previous study [ 1 ] except for some adjustments for the martensite phase due to the introduction of the new combined hardening rule.
Journal Article

A Mixed-Mode Fracture Criterion for AHSS Cracking Prediction at Large Strain

2011-04-12
2011-01-0007
Predicting AHSS cracking during crash events and forming processes is an enabling technology for AHSS application. Several fracture criteria including MatFEM and Modified Mohr-Coulomb Criterion were developed recently. However, none of them are designed to cover more fracture modes such as bending fracture and tearing fracture with initial damage. A mixed-mode fracture criterion (MMFC) is proposed and developed to capture multiple fracture modes including in-plane shearing fracture, cross-thickness shearing fracture with bending effect and tearing fracture with initial damage. The associated calibration procedure for this criterion is developed. The criterion is implemented in a commercial FEA code and several lab validations are conducted. The results show its promising potential to predict AHSS cracking at large strain conditions.
Journal Article

Self-Pierce Riveting of Magnesium to Aluminum Alloys

2011-04-12
2011-01-0074
Magnesium and aluminum alloys offer lightweighting opportunities in automotive applications. Joining of dissimilar materials, however, generally requires methods that do not involve fusion. This paper explores the use of self-pierce riveting (SPR) to join magnesium to aluminum alloys for structural and closure applications. The preliminary results indicate that SPR is a viable option for joining aluminum extrusions to magnesium die castings, as well as stamped sheet aluminum to quick-plastic-formed (QPF) sheet magnesium.
Journal Article

The Effectiveness of Curtain Side Air Bags in Side Impact Crashes

2011-04-12
2011-01-0104
Accident data show that the head and the chest are the most frequently injured body regions in side impact fatal accidents. Curtain side air bag (CSA) and thorax side air bag (SAB) have been installed by manufacturers for the protection devices for these injuries. In this research, first we studied the recent side impact accident data in Japan and verified that the head and chest continued to be the most frequently injured body regions in fatal accidents. Second, we studied the occupant seating postures in vehicles on the roads, and found from the vehicle's side view that the head location of 56% of the drivers was in line or overlapped with the vehicle's B-pillar. This observation suggests that in side collisions head injuries may occur frequently due to contacts with the B-pillar. Third, we conducted a side impact test series for struck vehicles with and without CSA and SAB.
Journal Article

Experimental Investigation of Droplet Dynamics and Spray Atomization inside Thermostatic Expansion Valves

2011-04-12
2011-01-0129
In this paper, experimental investigation on spray atomization and droplet dynamics inside a thermostatic expansion valve (TXV), a component commonly used in vehicle refrigeration system, was conducted. A needle and an orifice were copied from a commercial TXV and machined to be mounted inside a chamber with optical access so that the flow inside the TXV is simulated and visualized at the same time. The break-up and atomization of the refrigerant were documented near the downstream of the orifice under different feed conditions for two TXV with different geometry. A Phase Doppler Anemometry (PDA) system was used later to measure the size and velocity of atomized refrigerant droplets. The results showed that the droplet size variation along the radial direction is slightly decreased at near downstream and increased at farther downstream due to the coalescence.
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