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All but a small fraction of human space radiation exposure has been in Low Earth Orbit (LEO) where significant protection from extraterrestrial ionizing radiation is provided as a result of its deflection in the Earth's magnetic field. The placement of a manned outpost at the L1 Lagrange Point could mark the first long-term venture into a “deep space” radiation environment, giving rise to the associated problems of long-term space exposure. One of the first issues to address is providing protection within an L1 station from a large solar particle event. A safe haven area could be used over the duration of the event or one may consider the sleep stations where it is already necessary to have added shielding. The surrounding bodies of other closely packed crewmembers in such a shelter are expected to provide a significant fraction of a crewmember's total shielding.

Automotive suppliers provide multi-layer trims mainly made of porous materials. They have a real expertise on the characterization and the modeling of poro-elastic materials. A dozen parameters are used to characterize the acoustical and elastical behavior of such materials. The recent vibro-acoustic simulation tools enable to take into account this type of material but require the Biot parameters as input. Several characterization methods exist and the question of reproducibility and confidence in the parameters arises. A Round Robin test was conducted on three poro-elastic material with four laboratories. Compared to other Round Robin test on the characterization of acoustical and elastical parameters of porous material, this one is more specific since the four laboratories are familiar with automotive applications. Methods and results are compared and discussed in this work.

Experimental or observed rolling resistance data can be utilized to develop an empirical model that accurately depicts tire rolling resistance as a function of load and pressure over a wide range of load and pressure variations. This method allows the development of a graphical expression (carpet plot) or mathematical expression (computer modeled) to depict rolling resistance on three “control tires.” When the graphical or computer modeled systems are combined with a basic control tire correlation concept, a rather accurate inter-test facility prediction system does not have to rely on the sometimes inaccurate correction equations developed from theoretical modeling techniques.

New in this study is the mathematical formula for calculating energy dissipated due to sliding under the action of Coulomb kinetic friction in the context of Impulse Momentum Planar Collision (IMPC) with isotropic restitution. The surface sliding dissipated energy theorem established here is precisely consistent with the laws of physics underlying IMPC. A principal goal of distinguishing between surface sliding energy dissipation and energy dissipation due to vehicle crush is to improve the rational basis for use of crush energy analysis with IMPC. Also new in this study is a consistent interpretation of Newton's, Poisson's and Stronge's restitution hypotheses as they apply to IMPC with Coulomb kinetic friction. While this paper adds to the understanding of energy dissipation, the IMPC method presented here is not new.

The Particulate Matter (PM) emissions from a diesel passenger car were measured using three units concurrently: a commercially-available opacimeter (Celesco), a Tapered Element Oscillating Microbalance (TEOM) and a Legal Particulate Sampling (LPS) unit consisting of dilution tunnel with Constant Volume Sampling (CVS). The opacimeter provides a time resolved measurement for the visible component of the Particulate Matter (PM); the TEOM does the same for particulate mass. The motivation was to determine whether the opacimeter or TEOM could be used to suggest the likely result with CVS during transient engine operation. This would be accomplished more conveniently by empirical correlations, but with the advantage, that temporal variations during transients are then available. Forty-seven tests were conducted on a 4-cylinder 1.8l Turbo-Diesel Common-Rail Injection (TDCi) engine, operated under transient conditions according to the European Extra-Urban Drive Cycle (0-70kph EUDC).

Using multiple body scans of 20 adult females, inter-individual body shape change patterns were analyzed. A homologous shape model was created for each body scan, and intra-individual shape change pattern before and after a sliming program was formulated using a deformed grid of FFD. The deformed grids were normalized for the size, and were analyzed for variations in shape change patterns using PCA and MDS. Based on the efficiency in information compression and the relationship with changes in body dimensions, MDS was more useful for this purpose.

Already established driver assistance systems like Cruise Control or Adaptive Cruise Control are based on the delegation of a part of the driving task to the system. Instead of keeping a suitable speed the driver is just monitoring the correct function of the assistance system. In situations when the system is fulfilling the task in a way the driver doesn't accept she / he has to deactivate it. Adding a new input element the driver gains the possibility to create additional inputs in terms of acceleration or deceleration to the assistance system. This allows the driver to modify the system behavior in different driving situations without deactivating the system. The relationship between driver and system shifts from “delegation” to “co-operation”. This paper explains principal aspects of the technical realization and presents the results of a study regarding the first contact of subjects with an enhanced Adaptive Cruise Control.

Knowledge of vehicle dynamics variables is very important for vehicle control systems that aim to improve handling characteristics and passenger safety. However for both technical and economical reasons some fundamental data (e.g., Lateral tire-road forces and vehicle sideslip angle) are difficult to measure in a standard car. This paper proposes a novel Interacting Multiple Model Filter-Based method to estimate lateral tire-road forces by utilizing real-time measurements. The estimation method of lateral tire-road forces is based on an interacting multiple model (IMM) filter that integrates in-vehicle sensors of in-wheel-motor-driven electric vehicles to adaptively adjusted multiple vehicle-road system models to match variable driving conditions. A four-wheel nonlinear vehicle dynamics model (NVDM) is built considering extended roll dynamics and load transfer.

SCONES (Stress CONcentration Expert System) software is used to predict stress concentrations. When dimensions and loads are modified it instantaneously updates the display, making the system easy to use. SCONES contains validated and extended data from various sources, including complex interacting features which augments SCONES role. However, the natural progression is to extend the research to the interaction of processes including, for example, surface processes like anodising. These process interactions will dovetail into, and enhance features within the strain life factors. This paper will describe new work which will extend current knowledge in feature interactions and strain life factors and will improve SCONES versatility.

Automatic transmissions equipped with Modulated Torque Converter Clutches (MTCC) require an effective combination of automatic transmission fluid (ATF) - friction material in order to maintain frictional integrity. However, in this study, thermal analysis has shown that ATFs can interact chemically with a friction material used in the MTCC under service conditions, potentially affecting the frictional characteristics. A technique was developed to evaluate friction material degradation. The results of this study showed that the friction material my be chemically altered by static aging in certain ATFs at elevated temperatures. The statically aged friction material samples exhibited thermal analysis signatures which were similar to identical material degraded during dynamometer and fleet vehicle tests. These vehicle tests resulted in deterioration in friction characteristics and experienced shudder.

Nowadays, the influence of aerodynamics on vehicles capabilities is mostly studied in terms of energy efficiency; maximum speed; maximum linear accelerations; cooling capacity of brake systems; resistance and deformation of elements exposed to aerodynamic forces; stability during lateral wind and during braking for straight ahead maneuvers; noise caused by airflow; proper evacuation of exhaust gases and aesthetics of cars. Generally, a model for CFD analysis is used and six constant coefficients are determined. However, there is insufficient information about the interaction of vehicle aerodynamics with vehicle suspension and the effects that this interaction generates on the dynamic behavior of the vehicle. In this work this interaction is studied, and there is an analysis of how vehicle aerodynamic characteristics impact on suspension behavior and how suspension characteristics could diminish or amplify aerodynamic.

Ceramic matrix composites (CMC) have been increasingly used as alternative materials of the rotors of friction brakes. However there is still a need for a better understanding of fundamentals of CMC rotors and their associated friction materials. In this paper, the friction performance at the initial stage was characterized by testing on a laboratory-scale dynamometer and a car for brakes consisting of rotors made of carbon-fiber-reinforced carbon-silicon carbide (Cf/C-SiC) composite, and pads with organic liners. The characteristics of friction surface and its evolution were studied through focused imaging on the surface of the rotor after testing on the dynamometer. Both dynamometer and vehicle tests showed that bedding was essential to reach the required coefficient of friction (CoF). Sustainable transfer layer was successfully deposited on the surface of silicon in the early stage of bedding, but the deposition became difficult on that of carbon constituents and silicon carbide.

Fuel additives are used in diesel fuel for various reasons. For example, poor lubricity of some low sulfur and ultra low sulfur fuels necessitate the addition of lubricity additives to maintain acceptable protection of fuel system components. However, with today's high pressure fuel systems and lubricant oil recycling practices, some lubricant mixing with the fuel is unavoidable. As a result, an increase in fuel filter plugging was reported when lubricant components are present in the fuel. This paper shows filter plugging resulted from the interaction of basic lubricant additives with acidic fuel additives. Attempts to reduce the plugging by supplemental fuel additives were technically successful, but not economically feasible. The linkage between filter plugging and additive interactions is demonstrated in this paper. Part II of this series will explore the mechanisms of the additive interactions, and other causes for filter plugging.

Sulfur containing species as well as other polar molecules provide lubricity and thermal stability to diesel fuels. During the refining process to produce low and ultra-low sulfur diesel fuels, these components are removed. As a result, fuel additives such as lubricity agents and antioxidant may be added to protect fuel stability and prevent fuel pump wear. Some lubricity additives, such as dimer acids, resulted in fuel filter plugging. The plugging mechanism was related to the capability of aliphatic acids to form agglomeration by interactions with the overbased detergents, delivered into the fuel as oil contaminants. Other sources of acids, derived from thermal degradation, can lead to the same problem. In this study, individual lubricant additives were mixed in the fuel to form single- and dual-component systems. Levels of compatibility and amounts of interaction products were evaluated for individual solutions.

The EPEFE study (European Programme on Emissions, Fuels and Engine Technologies), /1/ and other programmes have identified an increase in tailpipe NOx emissions with reduced gasoline aromatics content for modern 3-way controlled catalyst vehicles. This effect occurs with fully warmed-up catalyst under closed-loop operation. In order to understand the reasons for this effect VW and Shell have mechanistically investigated the effects of fuel properties on EMS (engine management system) and catalyst performance. Fuels with independent variation of oxygen, aromatics and mid-range volatility were tested in different VW engines. λ was monitored using sensors located both pre and post catalyst. The results confirmed that reducing gasoline aromatics content reduced engine-out emissions but increased tailpipe NOx emissions. It could be shown that differences in H/C ratio led to differences in the hydrogen content of engine-out emissions which affected the reading of the λ sensor.

This paper discusses road damage caused by heavy commercial vehicles. Chapter 1 presents some important terminology and a brief historical review of road construction and vehicle-road interaction, from ancient times to the present day. The main types of vehicle-generated road damage, and the methods that are used by pavement engineers to analyze them are discussed in Chapter 2. Attention is also given to the main features of the response of road surfaces to vehicle loads and mathematical models that have been developed to predict road response. Chapter 3 reviews the effects on road damage of vehicle features which can be studied without consideration of vehicle dynamics. These include gross vehicle weight, axle and tire configurations, tire contact conditions and static load sharing in axle group suspensions. The dynamic tire forces generated by heavy vehicles are examined in Chapter 4.

Turbulent flame speeds have been measured in a single cylinder S.I. engine and in a stationary atmospheric burner. One- and two-point LDA has been used to measure turbulence intensities and integral length scales. Stretching, in terms of Karlovitz numbers could be estimated from these measurements. The influence of moving average filtered turbulence on the flame speed in the S.I. engine is in agreement with the burner experiments. Previously reported signs of quenching of small flames in the S.I. engine, due to excessive turbulence could not be found for larger flames.

This paper presents an analytical treatment of a mechanical-mathematical model of an air bag inflation process integrated with a model for the interaction between the air bag and a standing child dummy. The inflation model consists of a one-dimensional gas dynamics analysis of the flow system which delivers the gas to inflate the bag. The interaction model then provides a method for calculating the forces exerted by the inflating bag on the standing child. The results show that the unacceptably high contact forces recorded in standing-child air bag tests are due to impact of the unopened portion of the bag on the standing child. A single-membrane concept is thus suggested to reduce this impact severity.

Past experiments have shown that numerous micro-hole sprays in close proximity produce drop sizes that are sensitive to the nozzle arrangement. Numerical studies have been performed to identify the interaction mechanisms between closely spaced sprays. It is shown that nozzle configurations can lower the drop-gas relative velocity and droplet Weber number, leading to reduced atomization intensity. However, the collisions involving droplets from neighboring sprays have a much greater effect on droplet size. Thus, neighboring sprays primarily interfere with each other through droplet collision.

Two imaging techniques are used to investigate the interaction between developed combustion from earlier injections and partially oxidized fuel (POF) of a subsequent injection. The latter is visualized by using planar laser induced fluorescence (PLIF) of formaldehyde and poly-cyclic aromatic hydrocarbons. High speed imaging captures the natural luminescence (NL) of the prevailing combustion. Three different fuel injection strategies are studied. One strategy consists of two pilot injections, with modest separations after each, followed by single main and post injections. Both of the other two strategies have three pilots followed by single main and post injections. The separations after the second and third pilots are several times shorter than in the reference case (making them closely-coupled). The closely-coupled cases have more linear heat release rates (HRR) which lead to much lower combustion noise levels.