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Injuries to the knee-thigh-hip (KTH) complex in frontal motor vehicle crashes are of substantial concern because of their frequency and potential to result in long-term disability. Current frontal impact Anthropometric Test Dummies (ATDs) have been shown to respond differently than human cadavers under frontal knee impact loading and consequently current ATDs (and FE models thereof) may lack the biofidelity needed to predict the incidence of knee, thigh, and hip injuries in frontal crashes. These concerns demand an efficient and biofidelic tool to evaluate the occurrence of injuries as a result of KTH loading in frontal crashes. The MADYMO human finite element (FE) model was therefore adapted to simulate bone deformation, articulating joints and soft tissue behavior in the KTH complex.

Virtual testing has grown to be an efficient tool in vehicle passive safety design. Most simulations currently are deterministic. Since the responses observed in real-life and standardized tests are greatly affected by scatter, a stochastic approach should be adopted in order to improve the predictability of the numerical responses with respect to the experimental data. In addition, an objective judgement of the performance of numerical models with respect to experimental data is necessary in order to improve the reliability of virtual testing. In the European VITES & ADVANCE project the software tool Adviser was developed in order to fulfil these two requirements. With Adviser, stochastic simulations can be performed and the quality of the numerical responses with respect to the experimental can be objectively rated using pre-defined and user-defined objective correlation criteria. The software Adviser was used to develop a stochastic HybridIII 50th% Madymo numerical model.

Whiplash injuries due to rear-end car collisions is one of the most aggravating traffic safety problems with serious implications for the European society. Yearly more than a million European citizens suffer neck injuries from rear-end car collisions, implying tremendous societal costs. Therefore the European Community has sponsored the European Whiplash project. The objective of this paper is to present a general overview of this project. Accident studies show the relevance of rear-impact- related whiplash injuries and representative rear impact conditions in which whiplash is likely to occur. For the development of a Rear Impact Dummy (RID) typical human responses to rear impact are needed and were obtained with human volunteer and Post Mortem Human Subject tests at low speeds. Accident reconstructions were performed in order to derive injury thresholds for the dummy.

Nowadays virtual testing and prototyping are generally accepted methods in crash safety research and design studies. Validated numerical crash dummy models are necessary tools in these methods. Computer models need to be robust, accurate and CPU efficient, where the balance between accuracy and efficiency is depending on the nature of the study performed. This paper presents the application of advanced multibody-modelling techniques, in order to generate crash dummy models that are accurate as well as CPU efficient. Two techniques, deformable body modelling and arbitrary surface modelling, are combined. Their application is presented by means of an example model: the Hybrid III 50th percentile thorax. The method for generating the model is explained, after which the accuracy and efficiency of the model is illustrated by presenting some simulation results.

The goal of this work was to investigate the possibilities of applying high EGR rates with low NOx and PM emission levels on a two-stage turbocharged 12 liter heavy duty diesel engine. The EGR is applied by using a long and short route EGR system. For the ESC operating points A25 and C100 EGR is applied, such that the NOx emission is 0.5 g/kWh. Lowest PM level and BSFC are achieved when long route EGR is applied in A25 and short route is applied in C100. Increasing the fuel line pressure is an effective way to reduce PM at high EGR rate engine running conditions. At a fuel line pressure of 2400 bar PM emission are 0.06 g/kWh for A25 and 0.54 g/kWh for C100. At C100 the PM reduction coincides with also a significant fuel consumption improvement. Retarding the injection timing at C100 can improve the PM emission further to a level of 0.13 g/kWh at the expense of an increase in BSFC.

Interaction of the human arm and deploying airbag has been studied in the laboratory using post mortem human subjects (PMHS). These studies have shown how arm position on the steering wheel and proximity to the airbag prior to deployment can influence the risk of forearm bone fractures. Most of these studies used older driver airbag modules that have been supplanted by advanced airbag technology. In addition, new numerical human body models have been developed to complement, and possibly replace, the human testing needed to evaluate new airbag technology. The objective of this study is to use a finite element-based numerical (MADYMO) model, representing the human arm, to evaluate the effects of advanced driver airbag parameters on the injury potential to the bones of the forearm. The paper shows how the model is correlated to Average Distal Forearm Speed (ADFS) and arm kinematics from two PMHS tests.

Pedestrians and cyclists are the most unprotected road users and their injury risk in case of accidents is significantly higher than for other road users. The understanding of the influence and sensitivity between important variables describing a pedestrian crash is key for the development of more efficient and reliable safety systems. This paper reflects the related work carried out within the AsPeCSS project. The results summarized out of virtual and physical tests provide valuable information for further development. 1168 virtual and 120 physical tests were carried out with adult and child pedestrian headform as well as upper and lower legform impactors representatives of 4 different vehicle front geometries in a wide range of impact speeds, angles and locations. This test matrix was based on previous work carried out within the AsPeCSS project.

This paper presents an automated fit for a control-oriented physics-based diesel engine combustion model. This method is based on the combination of a dedicated measurement procedure and structured approach to fit the required combustion model parameters. Only a data set is required that is considered to be standard for engine testing. The potential of the automated fit tool is demonstrated for two different heavy-duty diesel engines. This demonstrates that the combustion model and model fit methodology is not engine specific. Comparison of model and experimental results shows accurate prediction of in-cylinder peak pressure, IMEP, CA10, and CA50 over a wide operating range. This makes the model suitable for closed-loop combustion control development. However, NO emission prediction has to be improved.

A model-based control approach is proposed to give proper reference for the feed-forward combustion control of Partially Pre-mixed Combustion (PPC) engines. The current study presents a simplified first principal model, which has been developed to provide a base estimation of the ignition properties. This model is used to describe the behavior of a single-cylinder heavy-duty diesel engine fueled with a mix of bio-butanol and n-heptane (80vol% bio-butanol and 20 vol% n-heptane). The model has been validated at 8 bar gross Indicated Mean Effective Pressure (gIMEP) in PPC mode. Inlet temperature and pressure have been varied to test the model capabilities. First the experiments were conducted to generate reference points with BH80 under PPC conditions. And then CFD simulations were conducted to give initial parameter set up, e.g. fuel distribution, zone dividing, for the multi-zone model.

This paper presents a cylinder pressure-based control (CPBC) system for conventional diesel combustion with high EGR levels. Besides the commonly applied heat release estimation, the CPBC system is extended with a new virtual NOx and PM sensor. Using available cylinder pressure information, these emissions are estimated using a physically based combustion model. This opens the route to advanced On-Board Diagnostics and to optimized fuel consumption and emissions during all operating conditions. The potential of closed-loop CA50 and IMEP control is demonstrated on a multi-cylinder heavy-duty EGR engine. For uncalibrated injectors and fuel variations, the combustion control system makes the engine performance robust for the applied variations and reduces the need for a time-consuming calibration process. Cylinder balancing is shown to enable auto-calibration of fuel injectors and to enhance fuel flexibility.

This paper reports on a study of the TNO venturi EGR system and the Johnson Matthey CRT particulates trap on a DAF 355 kW engine. The results obtained indicate that this EGR-CRT combination is an effective means to achieve EURO-4 emission level, while maintaining good fuel economy. EGR strategy, injection timing and air-fuel ratio were optimised in such a way that good regeneration conditions were obtained across most of the engine operating map. Also transient EGR control is optimised to combine low NOx emission during the ETC with good driveability and good engine out particulates emission. The size of the oxidation catalyst in the CRT was investigated. It appeared that the larger oxidation catalyst showed a better regeneration performance during a low temperature duty-cycle. Negative aspects of a larger oxidation catalyst are increased costs and increased NO2 emission (because of the catalyst ability to oxidise more NO into NO2).

To meet future emission targets, it becomes increasingly important to optimize the synergy between engine and aftertreatment system. By using an integrated control approach minimal fluid (fuel and DEF) consumption is targeted within the constraints of emission legislation during real-world operation. In such concept, the on-line availability of engine-out NOx emission is crucial. Here, the use of a Virtual NOx sensor can be of great added-value. Virtual sensing enables more direct and robust emission control allowing, for example, engine-out NOx determination during conditions in which the hardware sensor is not available, such as cold start conditions. Furthermore, with use of the virtual sensor, the engine control strategy can be directly based on NOx emission data, resulting in reduced response time and improved transient emission control. This paper presents the development and on-line implementation of a Virtual NOx sensor, using in-cylinder pressure as main input.

Injury assessment reference values (IARV) predicting neck injuries are currently not available for side facing seated aircraft passengers in crash conditions. The aircraft impact scenario results in inertial loading of the head and neck, a condition known to be inherently different from common automotive side impact conditions as crash pulse and seating configurations are different. The objective of this study is to develop these IARV for the European Side Impact Dummy-2 (ES-2) previously selected by the US-FAA as the most suitable ATD for evaluating side facing aircraft seats. The development of the IARV is an extended analysis of previously published PMHS neck loads by identifying the most likely injury scenarios, comparing head-neck kinematics and neck loads of the ES2 versus PMHS, and development of injury risk curves for the ES2. The ES2 showed a similar kinematic response as the PMHS, particularly during the loading phase.

In this study a microwave assisted particulate trap regeneration system has been developed. Microwave technology typically shows uneven temperature distribution in a trap. In this research an innovative technique is introduced: a so-called circular polarizer for generating a more even energy distribution in the trap. Experimental work has been performed on a 1.2 l TDI engine on an engine dynamometer. A cordierite wall-flow trap was located in the exhaust pipe. Experiments have been performed with variation of temperature at the start of regeneration, energy input duration and external combustion air flow. It has been observed that the exhaust gas flow of the engine, even at idle, is too high for maintaining propagating flame fronts. It can be concluded that microwave regeneration with a low-power microwave generator of about 1 kW must be applied in a multiple branch trap system or regeneration events must be applied in periods when the engine is not running.

The application of SCR deNOx aftertreatment was studied on two about 12 liter class heavy-duty diesel engines within a consortium project. Basically, the system consists of a dosage system for aqueous urea injection and a vanadia based SCR catalyst, without an upstream or downstream oxidation catalyst. The urea injection system for a DAF and a Renault V.I. (Véhicules Industriels) diesel engine was calibrated on the engine test bench taking into account dynamic effects of the catalyst. For both engine applications NOx reduction was 81% to 84% over the ESC and 72% over the ETC. CO emission increased up to 27%. PM emission is reduced by 4 to 23% and HC emission is reduced by more than 80%. These results are achieved with standard diesel fuel with about 350 ppm sulfur. The test engines and SCR deNOx systems were built into a DAF FT95 truck and a Renault V.I. Magnum truck.

On behalf of NHTSA, the European commission and the Dutch Ministry of Traffic and Transport, the Safety department of TNO Automotive is performing numerical fleet studies using multi-body vehicle models. Currently nine vehicle models are available, each of a different vehicle class, two vehicle models with a modified front-structure. The aim is to develop strategies for evaluation of front-end structures minimizing the total harm in car-to-car crashes on a fleet-wide basis in different accident scenarios. For these studies multi-body models were constructed from existing finite element models. Front-end structure and passenger cell were modeled in detail to provide realistic deformation modes. Furthermore dummies, airbags, belts and main interior parts like dashboard and steering wheel were included. To qualify the performance of the multi-body vehicle models for crashworthiness in an entire fleet, a study on offset frontal angled impacts was performed.

Six European laboratories have evaluated the biomechanical response of the new advanced frontal impact dummy THOR-alpha with respect to the European impact response requirements. The results indicated that for many of the body regions (e.g., shoulder, spine, thorax, femur/knee) the THOR-alpha response was close to the human response. In addition, the durability, repeatability and sensitivity for some dummy regions have been evaluated. Based on the tests performed, it was found that the THOR-alpha is not durable enough. The lack in robustness of the THOR-alpha caused a problem in completing the full test program and in evaluating the repeatability of the dummy. The results have demonstrated that the assessment of frontal impact protection can be greatly improved with a more advanced frontal impact dummy. Regarding biofidelity and injury assessment capabilities, the THOR-alpha is a good candidate however it needs to be brought up to standard in other areas.

Premixed combustion concepts like PCCI and RCCI have attracted much attention, since these concepts offer possibilities to reduce engine out emissions to a low level, while still achieving good efficiency. Most RCCI studies use a combination of a high-cetane fuel like diesel, and gasoline as low-cetane fuel. Limited results have been published using natural gas as low-cetane fuel; especially full scale engine results. This study presents results from an experimental study of diesel-CNG RCCI operation on a 6 cylinder, 8 l heavy duty engine with cooled EGR. This standard Tier4f diesel engine was equipped with a gas injection system, which used single point injection and mixed the gaseous fuel with air upstream of the intake manifold. For this engine configuration, RCCI operating limits have been explored. In the 1200-1800 rpm range, RCCI operation with Euro-VI engine out NOx and soot emissions was achieved between 2 and 9 bar BMEP without EGR.

This paper presents the identification and validation of a dynamic Waste Heat Recovery (WHR) system model. Driven by upcoming CO₂ emission targets and increasing fuel costs, engine exhaust gas heat utilization has recently attracted much attention to improve fuel efficiency, especially for heavy-duty automotive applications. In this study, we focus on a Euro-VI heavy-duty diesel engine, which is equipped with a Waste Heat Recovery system based on an Organic Rankine Cycle. The applied model, which combines first principle modeling with stationary component models, covers the two-phase flow behavior and the effect of control inputs. Furthermore, it describes the interaction with the engine on both gas and drivetrain side. Using engine dynamometer measurements, an optimal fit of unknown model parameters is determined for stationary operating points.

Active safety systems are increasingly becoming available in trucks and passenger vehicles. Developments in the field of active safety are shifting from increasing driver comfort towards increasing occupant safety. Furthermore, this shift is seen within active safety systems: safety functions are added to existing comfort systems, rather than adding new safety systems to the vehicle. Comfort systems such as cruise control are extended via ACC to pre-crash braking systems. Testing of active safety systems must follow these developments. Whereas standardized test programs are available for passive safety systems, such test programs are hardly available yet for active safety systems. Furthermore, test programs for passive safety systems consist of only a handful of scenarios. Test programs for active safety systems, however, should consist of much more scenarios, as those systems should function well in many different situations.