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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.

This investigation addresses and evaluates: (1) belted drivers in frontal crashes; (2) crashes divided into low, medium, and high severity; (3) air-bag-equipped passenger vehicles separated into either model years 1985 - 1997 (with airbags) or model years 1998 - 2008; (4) rate of Harm as a function of crash severity and vehicle model year; and (5) injury patterns associated with injured body regions and the involved physical components, by vehicle model year. Comparisons are made between the injury patterns related to drivers seated in vehicles manufactured before 1998 and those manufactured 1998 or later. The purpose of this comparative analysis is to establish how driver injury patterns may have changed as a result of the introduction of more recent safety belt technology, advanced airbags, or structural changes.

For children seated next to the struck side, real-world crash outcome was determined for the rear-seat of passenger vehicles over the entire range of side impact crash severities. The method was first to calculate the actual risk for an occupant based on field data. The data sources were non-rollover, tow-away crashes from the 1997 - 2009 National Automotive Sampling System. By limiting the struck passenger vehicle to model year 1985 or newer, field data were identified for a total of 588 children. In all crashes, the child was seated in the rear-seat area on the struck side of the passenger vehicle. A matrix of MADYMO model simulations calculated the response of child dummies over the entire range of the field data. Age-dependent, moderate-to-serious (AIS ≥ 2) injury risk curves were derived and evaluated for children in side impact. Risks to the children were calculated by combining the derived child risk curves with the MADYMO model simulations.

In recent years a new combustion phenomenon called Low-Speed Pre-Ignition (LSPI) occurred, which is the most important limiting factor to exploit further downsizing potential due to the associated peak pressures and thus the huge damage potential. In the past there were already several triggers for pre-ignitions identified, whereat engine oil seems to have an important influence. Other studies have reported that detached oil droplets from the piston crevice volume lead to auto-ignition prior to spark ignition. However, wall wetting and subsequently oil dilution and changes in the oil properties by impinging fuel on the cylinder wall seem to have a significant influence in terms of accumulation and detachment of oil-fuel droplets in the combustion chamber. For this reason, the influence of test fuels with different volatility were investigated in order to verify their influence on wall wetting, detachment and pre-ignition tendency.

Vehicle steering control can provide assistance to drivers for lane keeping, automated trajectory following, or more extreme evasive maneuvers. An active torque control steering system is designed using Linear Quadratic Regulator (LQR), and its performance was evaluated using the commercial software CARSIM. The system is developed to maintain a desired trajectory for the vehicle in performing evasive maneuvers to avoid imminent crash scenarios. In order to better understand the behavior of the system with different controllers, a simple bicycle model of the vehicle was developed, and an LQR controller was developed to control vehicle steering torque. The controller uses yaw angle, yaw rate, velocity, and position of the vehicle to generate the required steering torque to follow the desired trajectory. An observer was developed to estimate non-measured parameters. Trajectories are generated to follow a lane change before reaching the obstacle.

Battery packs for Hybrids, Plug-in Hybrids, and Electric Vehicles are assembled from a system of modules (sheets) with a tight sheet metal casing around them. Each module consists of an array of individual cells which vary in the composition of electrodes and separator from one manufacturer to another. In this paper a general procedure is outlined on the development of a constitutive and computational model of a cylindrical cell. Particular emphasis is placed on correct prediction of initiation and propagation of a tearing fracture of the steel can. The computational model correctly predicts rupture of the steel can which could release aggressive chemicals, fumes, or spread the ignited fire to the neighboring cells. The initiation site of skin fracture depends on many factors such as the ductility of the casing material, constitutive behavior of the system of electrodes, and type of loading.

The National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the barrier in crash tests. Thirty-six load cells on the face of the rigid barrier measure the force. This study examines the load cell barrier data collected during recent years of NCAP testing to determine how it can be used to assess vehicle compatibility in vehicle-to-vehicle front-to-side crashes. The height of the center-of-force measured by the columns of load cells is proposed as a metric for quantitatively describing the geometric properties of the crash forces. For front-to-side crashes, the geometric and stiffness properties of frontal structures during the early stages of crush are applicable. Consequently, geometric and stiffness measurements at a crush of 125 mm are presented in this paper. This paper shows the range of the compatibility and stiffness parameters measured on cars, pickups, vans, and multi-purpose vehicles.

Most major regional automotive markets have stringent legislative targets for vehicle greenhouse gas emissions or fuel economy enforced by fiscal penalties. Large improvements in vehicle efficiency on mandated test cycles have already taken place in some markets through the widespread adoption of technologies such as downsizing or dieselisation. There is now increased focus on approaches which give smaller, but significant incremental efficiency benefits, such as reducing parasitic losses due to engine friction. The reduction in tail pipe CO2 emissions through the reduction of engine friction using lubricants has been reported by many authors. However, opportunities also exist to reduce the lubricant viscosity during warm up by the thermal management of the lubricant mass.

It has been observed that a certain percentage of diesel particulate filters (DPFs) from the field form mid-channel ash plugs both in light duty and heavy duty applications. As revealed in a post mortem study, some field samples have ash plugs of 3-10 cm length in the middle of DPF inlet channels, which can potentially reduce the inlet channel volume by more than 50%. As a result, the mid-channel ash plug reduces the effective filtration area and decreases the effective channel open width in the middle of the channel. This explains why these filters are reported as having large increases in pressure drop. Moreover, the mid-channel ash deposits reduce the DPF service life and render the filter cleaning process ineffective. In the present study, an open source CFD tool is applied to study the 3D flow crossing two representative inlet and outlet DPF channels where the inlet channels have mid-channel ash plugs.

Knocking combustion places a major limit on the performance and efficiency of spark ignition engines. Spontaneous ignition of the unburned air-fuel mixture ahead of the flame front leads to a rapid release of energy, which produces pressure waves that cause the engine structure to vibrate at its natural frequencies and produce an audible ‘pinging’ sound. In extreme cases of knock, increased temperatures and pressures in the cylinder can cause severe engine damage. Damage is thought to be caused by thermal strain effects that are directly related to the heat flux. Since it will be the maximum values that are potentially the most damaging, then the heat flux needs to be measured on a cycle-by-cycle basis. Previous work has correlated heat flux with the pressure fluctuations on an average basis, but the work here shows a correlation on a cycle-by-cycle basis. The in-cylinder pressure and surface temperature were measured using a pressure transducer and eroding-type thermocouple.

In recent years concern has arisen over a new combustion anomaly, which was not commonly associated with naturally aspirated engines. This phenomenon referred to as Low-Speed Pre-Ignition (LSPI), which often leads to potentially damaging peak cylinder pressures, is the most important factor limiting further downsizing and the potential CO2 benefits that it could bring. Previous studies have identified several potential triggers for pre-ignition where engine oil seems to have an important influence. Many studies [1], [2] have reported that detached oil droplets from the piston crevice volume lead to auto-ignition prior to spark ignition. Furthermore, wall wetting and subsequently oil dilution [3] and changes in the oil properties by impinging fuel on the cylinder wall seem to have a significant influence in terms of accumulation and detachment of oil-fuel droplets in the combustion chamber.

The fuel effects on HCCI operation in a spark assisted direct injection gasoline engine are assessed. The low load limit has been extended with a pilot fuel injection during the negative valve overlap (NVO) period. The fuel matrix consists of hydrocarbon fuels and various ethanol blends and a butanol blend, plus fuels with added ignition improvers. The hydrocarbon fuels and the butanol blend do not significantly alter the high or the low limits of operation. The HCCI operation appears to be controlled more by the thermal environment than by the fuel properties. For E85, the engine behavior depends on the extent that the heat release from the pilot injected fuel in the NVO period compensates for the evaporative cooling of the fuel.

Research Octane Number (RON) and Motor Octane Number (MON) are used to describe gasoline combustion which describe antiknock performance under different conditions. Recent literature suggests that MON is less important than RON in modern cars and a relaxation in the MON specification could improve vehicle performance. At the same time, for the same octane number change, increasing RON appears to provide more benefit to engine power and acceleration than reducing MON. Some workers have advocated the use of an octane index (OI) which incorporates both parameters instead of either RON or MON to give an indication of gasoline knock resistance. Previous Concawe work investigated the effect of RON and MON on the power and acceleration performance of two Euro 4 gasoline passenger cars during an especially-designed acceleration test cycle.

The research question investigated in this study is what are the key attributes of foot and ankle injury in the between-rail frontal crash? For the foot and ankle, what was the type of interior surface contacted and the type of resulting trauma? The method was to study with in-depth case reviews of NASS-CDS cases where a driver suffered an AIS=2 foot or ankle injury in between-rail crashes. Cases were limited to belted occupants in vehicles equipped with air bags. The reviews concentrated on coded and non-coded data, identifying especially those factors contributing to the injuries of the driver's foot/ankle. This study examines real-world crash data between the years 1997-2009 with a focus on frontal crashes involving 1997 and later model year vehicles. The raw data count for between-rail crashes was 732, corresponding to 227,305 weighted, tow-away crashes.

The William Lehman Injury Research Center has conducted multi-disciplinary investigations of one hundred seventy-eight crashes involving adult occupants protected by safety belts and air bags. In all cases, serious injuries were suspected. Nine cases involved serious heart injuries. These cases are not representative of crashes in general. However, when used in conjunction with National Accident Sampling System; Crashworthiness Data System (NASS/CDS) they provide insight into the most severe injuries suffered by restrained occupants in frontal crashes. Heart injuries are rare, but when they occur they are usually life threatening. NASS/CDS shows that heart injuries comprise about 0.2% of the injuries in frontal tow-away crashes. In the NHTSA file of Special Crash Investigations (SCI) of air bag cases, heart injuries are reported in 1% of the occupants over 15 years of age. Twenty-five percent of the fatally injured occupants had heart injuries, and 83% of those with heart injury died.

While the present air bag systems have been shown to be highly effective in high severity crashes, undesirable side effects have been reported in some low severity events. The inflation rate of the airbag during deployment has been cited as a factor which induces injuries. A rapid airbag deployment rate is advantageous to provide protection to occupants in severe crashes. On the other hand, airbag aggressivity associated with the high inflation rate can increase injuries in the lower severity crashes. The injury producing forces from the airbag increase as the occupant position becomes closer to the bag at the time of deployment. This paper describes the results of an analytical study to evaluate chest injury measures for reduced inflation rates of a Taurus type air bag in a variety of crash modes. A detailed nonlinear finite element model of an unfolding airbag and a 50th percentile male Hybrid III dummy are used in conjunction with a test buck to simulate frontal crashes.

Engineering practice routinely involves decision making under uncertainty. Much of this decision making entails reconciling multiple pieces of information to form a suitable model of uncertainty. As more information is collected, one expectedly makes better and better decisions. However, conditional probability assessments made by human decision makers, as new information arrives does not always follow expected trends and instead exhibits inconsistencies. Understanding them is necessary for a better modeling of the cognitive processes taking place in their mind, whether it be the designer or the end-user. Doing so can result in better products and product features. Quantum probability has been used in the literature to explain many commonly observed deviations from the classical probability such as: question order effect, response replicability effect, Machina and Ellsberg paradoxes and the effect of positive and negative interference between events.

This paper examines injuries and injury mechanisms in side impact crashes being addressed by the United States standard, FMVSS 214. In this side impact protection standard, a moving deformable barrier impacts the occupant compartment of a vehicle being tested. The moving barrier is crabbed at an angle of 23 degrees measured relative to the side of the struck vehicle. The standard assesses the crash protection provided in a vehicle-to-vehicle crash to an occupant seated on the struck side, in the vicinity of the maximum intrusion. The National Automobile Sampling System /Crashworthiness Database System (NASS/CDS) data indicates that 75% AIS 3+ injuries occur in vehicle-to-vehicle crashes, 66% occur to the struck side occupants and 94% occur in crashes with damage to the occupant compartment. Crash directions of 10 and 2 o’clock are the most common injury producing crashes.

Knowledge of fuel mass injected in an individual cycle is important for engine performance and modelling. Currently direct measurements of fuel flow to individual cylinders of an engine are not possible on-engine or in real-time due to a lack of available appropriate measurement techniques. The objective of this work was to undertake real-time Coriolis fuel flow measurement using GDI injectors on a rig observing fuel mass flow rate within individual fuel injections. This paper evaluates the potential of this technology - combining Coriolis Flow Meters (CFMs) with Prism signal processing together known as Fast Next Generation Coriolis (Fast NGC), and serves as a basis for future transitions on-engine applications. A rig-based feasibility study has been undertaken injecting gasoline through a GDI injector at 150 bar in both single shot mode and at a simulated engine speeds of 1788 and 2978 rpm. The results show that these injections can, in principle, be observed.

For efficiency, the majority of modern diesel engines implement multiple injection strategies, increasing the frequency of transient injection phases and thus, end of injection (EOI) events. Recent advances in diagnostic techniques have identified several EOI phenomena pertinent to nozzle surface wetting as a precursor for deposit formation and a potential contributor towards pollutant emissions. To investigate the underlying processes, highspeed optical measurements at the microscopic scale were performed inside a motored diesel engine under low load/idling conditions. Visualisation of the injector nozzle surface and near nozzle region permitted an indepth analysis of the post-injection phenomena and the behaviour of fuel films on the nozzle surface when the engine is not fired. Inspection of the high-speed video data enabled an interpretation of the fluid dynamics leading to surface wetting, elucidating the mechanisms of deposition and spreading.