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Selective Catalytic Reduction (SCR) of NO using reductants such as urea continues to be of high interest to meet impending regulations. Vanadia supported on anatase titania is a well-established catalyst for stationary and heavy-duty-diesel truck deNO applications. However, traditional anatase titania-based materials are regarded to have limited thermal stability in the most demanding applications such as those where the SCR catalyst is located downstream of a regenerating DPF, in which the catalyst could be exposed to very high temperatures. More recently, state-of-the-art titania-based vanadia catalysts have shown good cold-start performance and are capable of surviving accelerated aging treatments of up to 64 hrs at 670°C, good performance in a configuration upstream of a DOC/DPF, good low temperature NO conversion on par with Cu-zeolite SCR catalysts and superior resistance to sulfur poisoning.

Far-side occupants are not addressed in current government regulations around the world even though they account for up to 40% of occupant HARM in side impact crashes. Consequently, there are very few crash tests with far-side dummies available to researchers. Sled tests are frequently used to replicate the dynamic conditions of a full-scale crash test in a controlled setting. However, in far-side crashes the complexity of the occupant kinematics is increased by the longer duration of the motion and by the increased rotation of the vehicle. The successful duplication of occupant motion in these crashes confirms that a sled test is an effective, cost-efficient means of testing and developing far-side occupant restraints or injury countermeasures.

The recent development of diesel engine fuel injection systems has been dominated by how to manage the degrees of freedom that common rail multi-pulse systems now offer. A number of production engines already use four injection events while in research, work based on up to eight injection events has been reported. It is the degrees of freedom that lead to a novel experimental requirements. There is a potentially complex experimental program needed to simply understand how injection parameters influence the combustion process in steady state. Combustion behavior is not a continuum and as both injection and EGR rates are adjusted, distinct combustion modes emerge. Conventional calibration processes are severely challenged in the face of large number of degrees of freedom and as a consequence new development approaches are needed.

For accurately predicting different fracture patterns of the pelvis frequently observed in pedestrian accidents with SUV/Mini-van, human finite element (FE) models have been developed. Although those models with failure representation can predict occurrence or nonoccurrence of fractures, quantitative estimation of probability of fractures is not possible. For human models without failure representation, typically stress or strain of elements is used for fracture prediction. However, numerous elements must be evaluated when fracture location is not predetermined. This study investigated methodology for accurately predicting probability of pelvic fractures using a minimal number of output parameters. The hood edge and upper and lower parts of the bumper were chosen for representing vehicle fronts. These components were modeled using rigid surfaces with the stiffness of them represented by springs, to constitute 3-component models.

With the objective of establishing the ultimate steering operation system for drivers, we developed, based on bioengineering considerations, the Twin Lever Steering (TLS) system which mimicks the bi-articular muscles, as shown in Fig. 1 . The bioengineering advantages are as follows: (1) force can be exerted more easily, (2) the steering can be accomplished quickly, (3) the positioning can be done accurately, and (4) the burden on the driver can be reduced (less fatigue). The advantages of the vehicle in terms of its motion are as follows: (1) the line-traceability is improved, (2) the drift control is improved, (3) the lane-change capability is improved, and (4) the lap time and stability are improved. We would like to report on these advantages of the TLS system from a bioengineering standpoint, and also describe the results of some verification test results obtained from vehicles equipped with this new steering system.

Forming simulation is a widely used tool to estimate production forming capabilities. During the last three to four years the prediction of process robustness by sensitivity analysis has been developed for industrial applications. The change of material parameters is one key figure and has a large impact on the final findings. Thus the user has to ensure that the variations done are in correlation with real material behaviour and the selected numerical model is reliable. Up to now the permitted changes in modelling are seldom secured by real measurements, especially when more advanced material models and hardening options are applied. Various materials chosen out of the production process for mild steel grades have been investigated for their mechanical properties using different tests. The limits of failure are defined by a reduced number of Nakajima tests to predict the forming limit curve (FLC). All data is prepared in the same manner to meet simulation program needs.

Approximately 600,000 fatalities occur each year as a result of pedestrians being impacted by motor vehicles (World Bank, 2008). Previous studies (Heller et al., 2009) have utilized databases such as the National Inpatient Sample (NIS) to gain a more thorough understanding of the common injury patterns that occur in real-world traffic collisions involving pedestrians in the United States. The NIS contains records on five to eight million hospital stays annually and provides a wealth of information regarding injuries to hospitalized pedestrian casualties in the U.S. Because of the large number of applicable records in the NIS and the randomized sampling procedure, the data can be used to complete analyses that are not possible with smaller databases such as the Pedestrian Crash Data Study (PCDS), which is not intended to be statistically representative of pedestrian crashes in general.

A detailed investigation of the influence of anisotropic hardening models on drawbead restraining force is presented in this paper. The recently modified Yoshida model is adopted to characterize the anisotropic hardening behavior for steels. A two-dimensional drawbead model is used and the restraining forces corresponding to several different bead penetrations are obtained and compared against experimental results. The comparison of the predicted results for the Modified Yoshida Model with isotropic hardening models indicates that the anisotropic hardening gives lower drawbead restraining forces in general. The impact of hardening models on springback is also presented, and it's demonstrated that the springback amount predicted by the modified Yoshida model is much closer to the experimental data than that predicted by conventional isotropic hardening model.

Multi-stage draw process is an important stamping method to make complex sheet metal parts for automotive industry. Due to complexity, its development is challenging and time consuming. In this study, the multi-stage draw development is modeled as a multi-stage decision making process. Based on sheet metal incremental plastic deformation theory, drawability and failure criteria, a dynamic programming type solution is proposed and demonstrated by FEM simulations on a rectangular geometry with high reduction ratio. Due to the recurrence nature of dynamic programming, the method provides a possibility of automatic process design of multi-stage draw.

One of the issues in stamping of advanced high strength steels (AHSS) is the stretch bending fracture on a sharp radius (commonly referred to as shear fracture). Shear fracture typically occurs at a strain level below the conventional forming limit curve (FLC). Therefore it is difficult to predict in computer simulations using the FLC as the failure criterion. A modified Mohr-Coulomb (M-C) fracture criterion has been developed to predict shear fracture. The model parameters for several AHSS have been calibrated using various tests including the butter-fly shaped shear test. In this paper, validation simulations are conducted using the modified (M-C) fracture criterion for a dual phase (DP) 780 steel to predict fracture in the stretch forming simulator (SFS) test and the bending under tension (BUT) test. Various deformation fracture modes are analyzed, and the range of usability of the criterion is identified.

Incremental Sheet Forming (ISF) is an emerging sheet metal prototyping technology where a part is formed as one or more stylus tools are moving in a pre-determined path and deforming the sheet metal locally while the sheet blank is clamped along its periphery. A deformation analysis of incremental forming process is presented in this paper. The analysis includes the development of an analytical model for strain distributions based on part geometry and tool paths; and numerical simulations of the forming process with LS-DYNA. A skew cone is constructed and used as an example for the study. Analytical and numerical results are compared, and excellent correlations are found. It is demonstrated that the analytical model developed in this paper is reliable and efficient in the prediction of strain distributions for incremental forming process.

The valve train plays a huge role in the performance of internal combustion engines by controlling the combustion process and is therefore one starting point to increase the efficiency of combustion engines. Considering the dynamics, the valve spring is the component with the lowest natural frequency in the motor and therefore plays a crucial role in the overall dynamics of the valve train. The spring force must be high enough to close the valve reliably and prevent the valves from bouncing of the seating due to surge modes after they have closed. Conversely, the spring force affect the friction level in the engine and therefore fuel consumption. For this reason the spring forces should be kept as low as possible. Modelling valve springs it has to be taken into account, that the dynamic response of the spring is substantially different from the static response.

Mechanisms of NH₃ generation using LNT-like catalysts have been studied in a bench reactor over a wide range of temperatures, flow rates, reformer catalyst types and synthetic exhaust-gas compositions. The experiments showed that the on board production of sufficient quantities of ammonia on board for SCR operation appeared feasible, and the results identified the range of conditions for the efficient generation of ammonia. In addition, the effects of reformer catalysts using the water-gas-shift reaction as an in-situ source of the required hydrogen for the reactions are also illustrated. Computations of the NH₃ and NOx kinetics have also been carried out and are presented. Design and impregnation of the SCR catalyst in proximity to the ammonia source is the next logical step. A heated synthetic-exhaust gas flow bench was used for the experiments under carefully controlled simulated exhaust compositions.

Accident data show that the injury risks to children seated in child restraint systems (CRSs) are higher in side collisions than any other type of collision. To investigate child injury in the CRS in a side impact, it is necessary to understand the occupant responses in car-to-car crash tests. In this research, a series of full car side impact tests based on the ECE R95 test procedure was conducted. In the vehicle's struck-side rear seat location, a Q3s three-year-old child dummy was seated in a forward facing (FF) CRS, and a CRABI six-month-old (6MO) infant dummy was seated in a rear facing (RF) CRS and also was placed in car-bed restraint. In the non-struck side rear seat location, the RF CRSs also were installed. In addition to testing the CRSs installed by a seatbelt, an ISOFIX FF CRS and an ISOFIX RF CRS were tested. For the evaluations, occupant kinematic behavior and injury measures were compared.

This paper presents a methodology for simulating Fluid Structure Interaction (FSI) for a typical vehicle bonnet (hood) under a range of onset flow conditions. The hood was chosen for this study, as it is one of the panels most prone to vibration; particularly given the trend to make vehicle panels lighter. Among the worst-case scenarios for inducing vibration is a panel being subjected to turbulent flow from vehicle wakes, and the sudden peak loads caused by emerging from a vehicle wake. This last case is typical of a passing manoeuvre, with the vehicle suddenly transitioning from being immersed in the wake of the leading vehicle, to being fully exposed to the free-stream flow. The transient flowfield was simulated for a range of onset flow conditions that could potentially be experienced on the open road, which may cause substantial vibration of susceptible vehicle panels.

Due to the increasingly stricter emission legislation and growing demands for lower fuel consumption, there have been significant efforts to improve combustion efficiency while satisfying the emission requirements. Homogeneous Charge Compression Ignition (HCCI) combined with turbo/supercharging on gasoline engines provides a particularly promising and, at the same time, a challenging approach. Naturally aspirated (n.a.) HCCI has already shown a considerable potential of about 14% in the New European Driving Cycle (NEDC) compared with a conventional 4-cylinder 2.0 liter gasoline Port Fuel Injection (PFI) engine without any advanced valve-train technology. The HCCI n.a. operation range is air breathing limited due to the hot residuals required for the self-ignition and to slow down reaction kinetics, and therefore is limited to a part-load operation area.

Hat sections made of steel are frequently encountered in automotive body structural components such as front rails. These components can absorb significant amount of impact energy during collisions thereby protecting occupants of vehicles from severe injury. In the initial phase of vehicle design, it will be prudent to incorporate the sectional details of such a component based on an engineering target such as peak load, mean load, energy absorption, or total crush, or a combination of these parameters. Such a goal can be accomplished if efficient and reliable data-based models are available for predicting the performance of a section of given geometry as alternatives to time-consuming and detailed engineering analysis typically based on the explicit finite element method.

This study presents an on-road evaluation of driver performance when controlling in-car technology via a handheld or voice-controlled interface. Participants drove with an experimenter on public roads while making mobile phone calls, having brief phone conversations, and playing tracks from a portable music player using both types of interface. The test vehicle was an instrumented 2010 Mercury Mariner equipped with the Ford SYNC® system, which allows for voice control of mobile phones and portable music devices. Twenty-one participants were tested, including 12 younger (19-34) and 9 older (39-51). All participants were owners of a vehicle equipped with the voice-control system, and all used the system regularly for phone calls and music playback.

This paper proposes a new motor design procedure for reducing motor loss in hybrid vehicles (HEV) and electric vehicles (EV). To find an optimum design in a short time, a non-linear magnetic circuit model was developed for interior permanent magnet synchronous motors (IPMSM). Speed-torque curves and motor losses were calculated based on this model. Combined with Energy Management Simulation, this model makes it possible to find an optimum motor design with minimum loss.

The low-temperature performance characteristics of a commercial lean NOX trap catalyst were evaluated using infra-red thermography (IRT) before and after a high-temperature aging step. Reaction tests included propylene oxidation, oxygen storage capacity measurements, and simulated cycling conditions for NOX reduction, using H₂ as the reductant during the regeneration step of the cycle. Testing with and without NO in the lean phase showed thermal differences between the reductant used in reducing the stored oxygen and that for nitrate decomposition and reduction. IRT clearly demonstrated where NOX trapping and regeneration were occurring spatially as a function of regeneration conditions, with variables including hydrogen content of the regeneration phase and lean- and rich-phase cycle times.