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In order to reduce fuel consumption, companies have been looking at hybridizing vehicles. So far, two main hybridization options have been considered: electric and hydraulic hybrids. Because of light duty vehicle operating conditions and the high energy density of batteries, electric hybrids are being widely used for cars. However, companies are still evaluating both hybridization options for medium and heavy duty vehicles. Trucks generally demand very large regenerative power and frequent stop-and-go. In that situation, hydraulic systems could offer an advantage over electric drive systems because the hydraulic motor and accumulator can handle high power with small volume capacity. This study compares the fuel displacement of class 6 trucks using a hydraulic system compared to conventional and hybrid electric vehicles. The paper will describe the component technology and sizes of each powertrain as well as their overall vehicle level control strategies.

In automotive body manufacturing the dies for blanking/trimming/piercing are under most severe loading condition involving high contact stress at high impact loading and large number of cycles. With continuous increase in sheet metal strength, the trim die service life becomes a great concern for industries. In this study, competing trim die manufacturing routes were compared, including die raw materials produced by hot-working (wrought) vs. casting, edge-welding (as repaired condition) vs. bulk base metals (representing new tools), and the heat treatment method by induction hardening vs. furnace through-heating. CaldieTM, a Uddeholm trademarked grade was used as trim die material. The mechanical tests are performed using a WSU developed trimming simulator, with fatigue loading applied at cubic die specimen’s cutting edges through a tungsten carbide rod to accelerate the trim edge damage. The tests are periodically interrupted at specified cycles for measurement of die edge damage.

Modeling plume interaction and collapse for direct-injection gasoline sprays is important because of its impact on fuel-air mixing and engine performance. Nevertheless, the aerodynamic interaction between plumes and the complicated two-phase coupling of the evaporating spray has shown to be notoriously difficult to predict. With the availability of high-speed (100 kHz) Particle Image Velocimetry (PIV) experimental data, we compare velocity field predictions between plumes to observe the full temporal evolution leading up to plume merging and complete spray collapse. The target “Spray G” operating conditions of the Engine Combustion Network (ECN) is the focus of the work, including parametric variations in ambient gas temperature. We apply both LES and RANS spray models in different CFD platforms, outlining features of the spray that are most critical to model in order to predict the correct aerodynamics and fuel-air mixing.

Hat-sections, single and double, made of steel are frequently encountered in automotive body structural components. These components play a significant role in terms of impact energy absorption during vehicle crashes thereby protecting occupants of vehicles from severe injury. However, with the need for higher fuel economy and for compliance to stringent emission norms, auto manufacturers are looking for means to continually reduce vehicle body weight either by employing lighter materials like aluminum and fiber-reinforced plastics, or by using higher strength steel with reduced gages, or by combinations of these approaches. Unlike steel hat-sections which have been extensively reported in published literature, the axial crushing behavior of hat-sections made of fiber-reinforced composites may not have been adequately probed.

A methodology has been developed for identifying the combination of battery characteristics which lead to least-cost electric vehicles. Battery interrelationships include specific power vs, specific energy, peak power vs. specific energy and DOD, cycle life vs. DOD, cost vs. specific energy and peak power, and volumetric and battery size effects. The method is illustrated for the “second car” mission assuming lead/acid batteries. Reductions in life-cycle costs associated with future battery research breakthroughs are estimated using a sensitivity technique. A research prioritization system is described.

A multi-axial test device was designed to obtain the material properties of the lumbar spine in combined loading modes. The custom designed tester consists of a rigid platen driven by three DC powered geared motors. Two motors, each connected to parallel linear actuators control the angular displacement (for flexion and extension) and vertical motion (for tension and compression), while a third DC motor connected to a threaded rod was employed to control the horizontal displacement (for anterior and posterior shear) of the rigid platen. The testing machine is driven in displacement-control mode by a feedback system based on data from three rotary potentiometers. Six entire lumbar spine segments (T12-S1) were potted in aluminum cups with DynaCast and tested within failure limits to compression, tension, anterior shear, posterior shear, flexion, extension, anterior shear-flexion, posterior shear-extension and finally in combined anterior shear-flexion loading.

A new friction testing system has been designed and built to simulate the actual engine conditions in friction and wear test of piston-ring and cylinder liner assembly. Experimental data has been developed as Friction Coefficient / Crank Angle Degree diagrams including the effects of running speed (500 and 700 rpm) and ring normal load. Surface roughness profilocorder traces were obtained for tested samples. Mixed lubrication regime observed in the most part of the test range. New cylinder bore materials and lubricants can be screened easily and more reliable simulated engine friction data can be collected using this technique.

Explicit finite element simulations were conducted on an aluminum wheel model where a rotating bend moment was applied on its hub to simulate wheel cornering fatigue testing. A post-processor was developed to calculate equivalent von Mises alternating and mean stresses from stress tensor. The safety factors of fatigue design for each finite element were determined to assess the fatigue performance by utilizing the Goodman linear relationship. Elements with low safety factors were identified due to the prescribed boundary conditions and stress concentrations arising from wheel geometry.

Road vehicles can expend a significant amount of energy in undesirable vertical motions that are induced by road bumps, and much of that is dissipated in conventional shock absorbers as they dampen the vertical motions. Presented in this paper are some of the results of a study aimed at determining the effectiveness of efficiently transforming that energy into electrical power by using optimally designed regenerative electromagnetic shock absorbers. In turn, the electrical power can be used to recharge batteries or other efficient energy storage devices (e.g., flywheels) rather than be dissipated. The results of the study are encouraging - they suggest that a significant amount of the vertical motion energy can be recovered and stored.

A process to recover carbon fibers from obsolete polymer matrix composite (PMC) materials has been developed. Carbon fibers have been recovered from samples containing urethane-based or epoxy-based substrates. An experimental parametric study conducted on both the bench-scale and the pilot-scale has been done to determine the least-cost process conditions. Based on this study, we have evaluated process economics that suggested a payback of about one year. This process is also applicable to polymer matrix composite materials made with thermoplastic substrates. This paper presents the results of the experimental testing campaign and the results of the process economic analysis.

One-dimensional transient modeling techniques are adapted to analyze the thermal behavior of lean-burn after-treatment systems when active flow control schemes are applied. The active control schemes include parallel alternating flow, partial restricting flow, and periodic flow reversal (FR) that are found to be especially effective to treat engine exhausts that are difficult to cope with conventional passive flow converters. To diesel particulate filters (DPF), lean NOx traps (LNT), and oxidation converters (OC), the combined use of active flow control schemes are identified to be capable of shifting the exhaust gas temperature, flow rate, and oxygen concentration to more favorable windows for the filtration, conversion, and regeneration processes. Comparison analyses are made between active flow control and passive flow control schemes in investigating the influences of gas flow, heat transfer, chemical reaction, oxygen concentration, and converter properties.

A unified approach has been developed and applied to solder joint life prediction in this paper, which indicates a breakthrough for solder joint reliability simulation. It includes the material characterization of solder alloys, the testing of solder joint specimens, a unified viscoplastic constitutive framework with damage evolution, numerical algorithm development and implementation, and experimental validation. The emphasis of this report focuses on the algorithm development and experimental verification of proposed viscoplasticity with damage evolution.

In an effort of providing better understanding of regeneration mechanisms of diesel particulate matter (PM), this experimental investigation focused on evaluating the amount of heat release generated during the thermal reaction of diesel PM and the concentrations of soluble organic compounds (SOCs) dissolved in PM emissions. Differences in oxidation behaviors were observed for two different diesel PM samples: a SOC-containing PM sample and a dry soot sample with no SOCs. Both samples were collected from a cordierite particulate filter membrane in a thermal reactor connected to the exhaust pipe of a light-duty diesel engine. A differential scanning calorimeter (DSC) and a thermogravimetric analyzer (TGA) were used to measure the amount of heat release during oxidation, along with subsequent oxidation rates and the concentrations of SOCs dissolved in particulate samples, respectively.

The adoption of lithium-ion batteries in vehicle electrification is fast growing due to high power and energy demand on hybrid and electric vehicles. However, the battery overall performance changes with time through the vehicle life. This paper investigates the electric vehicle battery cell aging under different usages. Battery cell experimental data including open circuit voltage and internal resistance is utilized to build a typical electric vehicle model in the AVL-Cruise platform. Four driving cycles (WLTP, UDDS, HWFET, and US06) with different ambient temperatures are simulated to acquire the battery cell terminal currents. These battery cell terminal current data are inputs to the MATLAB/Simulink battery aging model. Simulation results show that battery degrades quickly in high ambient temperatures. After 15,000 hours usage in 50 degrees Celsius ambient temperature, the usable cell capacity is reduced up to 25%.

Rigid polyurethane (PU) foam finds wide applications as a lightweight material in impact safety design such as improving occupant safety in vehicle crashes. The two principal reacting compounds for formulating such foam are variants of polyol and isocyanate. In the present study, an alternative mechanical engineering-based approach for determining, with confidence, the desirable ratio of reacting compounds for formulation of a rigid/crushable PU foam for mechanical applications is demonstrated. According to the present approach, PU foam samples are prepared by varying the mixing ratio over a wide range. The desirable mixing ratio is shown to be the one that optimizes key mechanical properties under compression such as total absorbed energy, specific absorbed energy and energy absorption efficiency.

A methodology for evaluating life cycle cost of electric vehicles (EVs) to their buyers is presented. The methodology is based on an analysis of conventional vehicle costs, costs of drivetrain and auxiliary components unique to EVs, and battery costs. The conventional vehicle's costs are allocated to such subsystems as body, chassis, and powertrain. In electric vehicles, an electric drive is substituted for the conventional powertrain. The current status of the electric drive components and battery costs is evaluated. Battery costs are estimated by evaluating the material requirements and production costs at different production levels; battery costs are also collected from other sources. Costs of auxiliary components, such as those for heating and cooling the passenger compartment, are also estimated. Here, the methodology is applied to two vehicle types: subcompact car and minivan.

A better understanding is needed of the electrostatic rotating bell (ESRB) application of metallic basecoat paint to automobile exteriors in order to exploit their high transfer efficiency without compromising the coating quality. This paper presents the initial results from experimental investigation of sprays from an ESRB which is designed to apply water-borne paint. Water was used as paint surrogate for simplicity. The atomization and transport regions of the spray were investigated using laser light sheet visualizations and phase Doppler particle analyzer (PDPA). The experiments were conducted at varying levels of the three important operating parameters: liquid flow rate, shaping-air flow rate, and bellcup rotational speed. The results show that bellcup speed dominates atomization, but liquid and shaping-air flow rate settings significantly influence the spray structure. The visualization images showed that the atomization occurs in ligament breakup regime.

Hollow polymer-based automotive components cannot, in general, be directly injection molded because they cannot be ejected from the mold. The common practice is to injection mold two or more parts, and then join these together with a welding process. Of the many joining process available, laser welding has an advantage in geometric design freedom. The laser weld joints are also generally stronger than those of vibration welds because the weld joints are located in the walls rather than on external flanges. Eliminating the external flanges also makes the part more compact. In transmission laser welding processes, the laser beam passes through a transparent part to its interface with an opaque part. The beam energy is absorbed near the interface in the opaque part, and heat flows back across to the transparent half to make the weld pool. So successful laser welds are possible only when there is a continuous interfacial fit between the parts.

Natural fiber-reinforced composites are currently gaining increasing attention as potential substitutes to pervasive synthetic fiber-reinforced composites, particularly glass fiber-reinforced plastics (GFRP). The advantages of the former category of composites include (a) being conducive to occupational health and safety during fabrication of parts as well as handling as compared to GFRP, (b) economy especially when compared to carbon fiber-reinforced composites (CFRC), (c) biodegradability of fibers, and (d) aesthetic appeal. Jute fibers are especially relevant in this context as jute fabric has a consistent supply base with reliable mechanical properties. Recent studies have shown that components such as tubes and plates made of jute-polyester (JP) composites can have competitive performance under impact loading when compared with similar GFRP-based structures.

With the increasing demand of emission reductions from the automotive industry, advanced after-treatment strategies have been investigated to overcome the challenges associated with meeting increasingly stringent emission regulations. Ongoing investigations on low temperature combustion (LTC) strategies are being researched to meet future emission regulations, however, the lowered exhaust temperature presents an even greater issue for exhaust after-treatment due to the change in combustion modes. Catalyst temperature is critical for the catalytic ability to maintain effective conversion efficiency of regulated emissions. The use of periodic flow reversal has shown benefits of maintaining catalyst temperature by alternating the exhaust flow direction through the catalytic converter, reducing the catalyst sensitivity to inlet gas temperature fluctuations.