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In recent truck applications, single-piece large-diameter propshafts, in lieu of two-piece propshafts, have become more prevalent to reduce cost and mass. These large-diameter props, however, amplify driveline radiated noise. The challenge presented is to optimize prop shaft modal tuning to achieve acceptable radiated noise levels. Historically, CAE methods and capabilities have not been able to accurately predict propshaft airborne noise making it impossible to cascade subsystem noise requirements needed to achieve desired vehicle level performance. As a result, late and costly changes can be needed to make a given vehicle commercially acceptable for N&V performance prior to launch. This paper will cover the development of a two-step CAE method to predict modal characteristics and airborne noise sensitivities of large-diameter single piece aluminum propshafts fitted with different liner treatments.

Friction Launch transmissions use a wet multi-plate clutch to replace the torque converter in an automatic transmission. By using one of the range clutches inside the transmission, the benefits of this integrated friction launch technology (IFL), such as reduction in mass, packaging, and cost, can be enhanced. The availability of new automatic transmissions with higher number of speeds and wider ratio spreads makes IFL technology more viable than ever before. The new GM Rear-Wheel-Drive (RWD) six-speed transmission has paved the way for a full implementation of integrated friction launch technology in a GM full size Sport-Utility Vehicle (SUV). This project focuses on both hardware and control issues with the friction launch clutch. The hardware issues include designing the clutch for launch energy, cooling, and durability.

Appropriate emergency response information is required for first responder before hydrogen fuel cell vehicles will become widespread. This paper investigates experimentally the hydrogen dispersion in the vicinity of a vehicle which accidentally releases hydrogen horizontally with a single volumetric flow of 2000 NL/min in the under-floor section while varying cross and frontal wind effects. This hydrogen flow rate represents normally a full throttle power condition. Forced wind was about maximum 2 m/s. The results indicated that the windward side of the vehicle was safe but that there were chiefly two areas posing risks of fire by hydrogen ignition. One was the leeward side of the vehicle's underbody where a larger region of flammable hydrogen dispersion existed in light wind than in windless conditions. The other was the area around the hydrogen leakage point where most of the leaked hydrogen remained undiffused in an environment with a wind of no stronger than 2 m/s.

The localized fire test provided in the Global Technical Regulation for Hydrogen Fuel Cell Vehicles gives two separate test methods: the ‘generic installation test - Method 1′ and the ‘specific vehicle installation test - Method 2′. Vehicle manufacturers are required to apply either of the two methods. Focused on Method 2, the present study was conducted to determine the characteristics and validity of Method 2. Test results under identical burner flame temperature conditions and the effects of cylinder protection covers made of different materials were compared between Method 1 and Method 2.

This paper describes the validation of RAMSIS, a 3-D CAD human model for ergonomic vehicle evaluation. At GM NAO, the model’s capability to correctly predict position and posture in vehicle CAD environments was tested. H- and Eye point locations between RAMSIS manikins and their human counterparts were compared. At GM/SAAB the model’s postural discomfort predictability was evaluated. Changes in postural discomfort predictions of the RAMSIS manikins were compared to that of the human subjects when they evaluated two different driving buck conditions. We concluded that RAMSIS has good position, posture and postural discomfort prediction capabilities and is a useful CAD ergonomic evaluation and design tool for vehicle interiors.

This paper presents an experimental comparative study between the OCTOGONAL-Gate Silicon-on-Insulator (SOI) nMOSFET (OSM) and the conventional SOI nMOSFET (CSM) considering the same bias conditions and the same gate area (AG), in order to verify the influence of this new MOSFET layout style to handle high current for automotive modules. Analog integrated circuits (ICs) design tends to be considered an art due to a large number of variables and objectives to achieve the product specifications. The designer has to find the right tradeoffs to achieve the desired automotive specification such as low power, low voltage, high speed and high current driver. SOI MOSFET's technology is required to provide the growth of embedded electronics. This growth is driving demand for power-handling devices that are smaller yet still provide high current driver capabilities.

In order to clarify future automobile technologies and fuel qualities to improve air quality, second phase of Japan Clean Air Program (JCAPII) had been conducted from 2002 to 2007. Predicting improvement in air quality that might be attained by introducing new emission control technologies and determining fuel qualities required for the technologies is one of the main issues of this program. Unregulated material WG of JCAPII had studied unregulated emissions from gasoline and diesel engines. Eight gaseous hydrocarbons (HC), four Aldehydes and three polycyclic aromatic hydrocarbons (PAHs) were evaluated as unregulated emissions. Specifically, emissions of the following components were measured: 1,3-Butadiene, Benzene, Toluene, Xylene, Ethylbenzene, 1,3,5-Trimethyl-benzene, n-Hexane, Styrene as gaseous HCs, Formaldehyde, Acetaldehyde, Acrolein, Benzaldehyde as Aldehydes, and Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene as PAHs.

An accurate prediction of internal nozzle flow in fuel injector offers the potential to improve predictions of spray computational fluid dynamics (CFD) in an engine, providing a coupled internal-external calculation or by defining better rate of injection (ROI) profile and spray angle information for Lagrangian parcel computations. Previous research has addressed experiments and computations in transparent nozzles, but less is known about realistic multi-hole diesel injectors compared to single axial-hole fuel injectors. In this study, the transient injector opening and closing is characterized using a transparent multi-hole diesel injector, and compared to that of a single axial hole nozzle (ECN Spray D shape). A real-size five-hole acrylic transparent nozzle was mounted in a high-pressure, constant-flow chamber. Internal nozzle phenomena such as cavitation and gas exchange were visualized by high-speed long-distance microscopy.

With rapid increase of vehicles on the road, safety concerns have become increasingly prominent. Since the leading cause of many traffic accidents is known to be by human drivers, developing autonomous vehicles is considered to be an effective approach to solve the problems above. Although trajectory tracking plays one of the most important roles on autonomous driving, handling the coupling between trajectory-tracking control and ESP under certain driving scenarios remains to be challenging. This paper focuses on trajectory-tracking control considering the role of ESP. A vehicle model is developed with two degrees of freedom, including vehicle lateral, and yaw motions. Based on the proposed model, the vehicle trajectory is separated into both longitudinal and lateral motion. The coupling effect of the vehicle and ESP is analyzed in the paper. The lateral trajectory-tracking algorithm is developed based on the preview follower theory.

Future automobiles are required to support an increasing number of complex, distributed functions such as active safety and X-by-wire. Because of safety concerns and the need to deliver correct designs in a short time, system properties should be verified in advance on function models, by simulation or model checking. To ensure that the properties still hold for the final deployed system, the implementation of the models into tasks and communication messages should preserve properties of the model, or in general, its semantics. FlexRay offers the possibility of deterministic communication and can be used to define distributed implementations that are provably equivalent to synchronous reactive models like those created from Simulink. However, the low level communication layers and the FlexRay schedule must be carefully designed to ensure the preservation of communication flows and functional outputs.

If a compressed hydrogen tank for vehicles is filled with hydrogen gas more quickly, the gas temperature in the tank will increase. In this study, we conducted hydrogen gas filling tests using the TYPE 3 and TYPE 4 tanks. During the tests, we measured the temperature of the internal liner surface and investigated its relationship with the gas temperature in the tank. We found that the gas temperature in the upper portion of the TYPE 4 tank rose locally during filling and that the temperature of the internal liner surface near that area also rose, resulting in a temperature higher than the gas temperature at the center of the tank. To keep the maximum temperature in the tank below the designed temperature (85°C) during filling and examine the representative tank internal temperatures, it is important to examine filling methods that can suppress local rises of tank internal temperature.

Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP).

There are now a wide variety of Hybrid and Electric Vehicles in or near production. They reduce or displace petroleum consumption with of various combinations of conventional IC engine, mechanical transmission, liquid fuel storage, electrical energy storage, electrical and electro-mechanical energy conversion, and vehicle-to-grid energy interface. These Electrified types of vehicles include Mild Hybrid, Full Hybrid, Plug-In Hybrid, Extended Range Electric, and Battery Electric. Some types differ in their actual usability for the real mixes of driving trips, and further that differ in their effectiveness to reduce or displace fuel in actual real world driving use. Vehicle size is also a factor in total vehicle utility in transporting people. If we may segment drivers by their driving needs, in each segment, we see a particular type of electrified vehicle that is better suited than others at minimizing fuel cost and petroleum consumption for the purposes of transporting people.

To reduce ultra fine particle number concentration from a heavy-duty diesel engine, the effects of diesel fuel property and after-treatment systems were studied. The reduction of ultra fine particle number concentration over steady state mode using an 8 liter turbocharged and after-cooled diesel engine was evaluated. PM size distribution was measured by a scanning mobility particle sizer (SMPS). The evaluation used a commercially available current diesel fuel (Sulfur Content: 0.0036 wt%), high sulfur diesel fuel (Sulfur Content: 0.046 wt%) and low sulfur diesel fuel (Sulfur Content: 0.007 wt%). The after-treatment systems were an oxidation catalyst, a wire-mesh type DPF (Diesel Particle Filter) and a wall-flow type catalyzed DPF. The results show that fine particle number concentration is reduced with a low sulfur fuel, an oxidation catalyst, a wire-mesh type DPF (Diesel Particulate Filter) and wall flow type catalyzed DPF, respectively.

To reduce NOx and Particulate Matter (PM) emissions from a heavy-duty diesel engine, the effects of urea selective catalytic reduction (SCR) systems were studied. Proto type urea SCR system was composed of NO oxidation catalyst, SCR catalyst and ammonia (NH3) reduction catalyst. The NOx reduction performance of urea SCR system was improved by a new zeolite type catalyst and mixer for urea distribution at the steady state operating conditions. NOx and PM reduction performance of the urea SCR system with DPF was evaluated over JE05 mode of Japan. The NOx reduction efficiency of the urea SCR catalyst system was 72% at JE05 mode. The PM reduction efficiency of the urea SCR catalyst system with DPF was 93% at JE05 mode. Several kinds of un-regulated matters were detected including NH3 and N2O leak from the exhaust gas. It is necessary to have further study for detailed measurements for un-regulated emissions from urea solution.

To reduce NOx emissions from a heavy-duty engine at low exhaust temperature conditions, the plasma-assisted SCR (Selective Catalytic Reduction) system was evaluated. The plasma-assisted SCR system is mainly composed of an ammonia gas supply system and a plasma reactor including a pellet type SCR catalyst. The preliminary test with simulated gases of diesel exhaust showed an improvement in the NOx reduction performance by means of the plasma-assisted SCR system, even below 150°C conditions. Furthermore, NOx reduction ratio was improved up to 77% at 110°C with increase in the catalyst volume. Also NOx emissions from a heavy-duty diesel engine over the transient test mode in Japan (JE05) were reduced by the plasma-assisted SCR system. However, unregulated emissions, e.g., aldehydes, were increased with the plasma environment. This paper reports the advantages and disadvantages of the plasma-assisted SCR system for a heavy-duty diesel engine.

To reduce emissions from diesel engines, the effects of oxidation catalysts on the emissions reductions were studied. The effectiveness of several oxidation catalysts on both the regulated and unregulated emissions was evaluated. The oxidation activity of the catalysts was varied by changing Pt loading. The regulated emissions include particulate (PM), hydrocarbon (HC), and carbon monoxide (CO), and the unregulated emissions include benzene, formaldehyde, acetaldehyde, and benzo[a]pyrene (B[a]P). An 8 litter, turbocharged and aftercooled diesel engine was operated under the Japan Diesel 13 (D13) mode cycle for the evaluations. As the first step, evaluations were conducted with a commercially available JIS #2 diesel fuel (0.046 wt% sulfur). All the regulated and unregulated emissions except PM were reduced as the Pt loading (i.e. oxidation activity) increased. However, PM emissions were increased by the generation of sulfate when the Pt loading exceeded 0.2 g/l.

The Chevrolet Volt is an electric vehicle (EV) with extended-range (ER) that is capable of operation on battery power alone, and on power generated by an on-board gasoline engine after depletion of the battery charge. For 2016, GM has developed the next generation of the Volt vehicle and “Voltec” propulsion system. Building on the experience of the first generation Volt, the second generation targeted improved all-electric range, improved charge sustaining fuel economy, and improved performance. All of this was to be accomplished while maintaining the EV character of the first generation Volt which customers clearly valued. This paper describes the next generation “Voltec” system and the realized improvements in efficiency and performance. The features of the propulsion system components, including energy storage, transaxle, electric motors and power electronics, on-board charging, and engine are described and compared with the previous generation.

The intention of this paper is to discuss the importance of analysis of some electrical parameters in order to design analog circuits in electronic modules, including automotive ones. Today, the challenge is to have devices which consume less power, high performance and higher integration density, so that it explains why such analysis is crucial to achieve better performances and meet the desired results.

Standard CFD methods require a mesh that fits the boundaries of the computational domain. For a complex geometry the generation of such a grid is time-consuming and often requires modifications to the model geometry. This paper evaluates the Immersed Boundary (IB) approach which does not require a boundary-conforming mesh and thus would speed up the process of the grid generation. In the IB approach the CAD surfaces (in Stereo Lithography -STL- format) are used directly and this eliminates the surface meshing phase and also mitigates the process of the CAD cleanup. A volume mesh, consisting of regular, locally refined, hexahedrals is generated in the computational domain, including inside the body. The cells are then classified as fluid, solid and interface cells using a simple ray-tracing scheme. Interface cells, correspond to regions that are partially fluid and are intersected by the boundary surfaces.