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There is a possibility that trace contaminants in the Shuttle Orbiter cabin atmosphere may chemically react with amine beads found in the Regenerative Carbon Dioxide Removal System and degrade system performance. Two contaminant compounds were exposed to the amine beads, and performance changes were measured. Acetone was tested because it is sometimes found in small but appreciable quantities in the cabin, and it has chemical properties that make it a potential poison. Halon 1301 was tested because it is the fire extinguishant, and a discharge of a Halon canister would trigger high concentrations in the cabin. Acetone was shown to be weakly and reversibly adsorbed. It does not poison the bed, and the RCRS was shown to remove small quantities of acetone. Halon was shown to be inert to the amine. It does not poison the RCRS, and is not removed by the RCRS.

Wire harness production is one of the most labour intensive and costly areas of aircraft production. Reduction in manufacturing cycle times and costs are presently key drivers in all areas of aerospace manufacture. The introduction of ultraviolet (UV) laser wire marking technology has already had a dramatic effect in helping to achieve these goals in the area of harness manufacture. The development of UV laser marking and its application to aerospace electrical harness production is reviewed. The advantages of laser technology in relation to factors such as machine set up times, throughput, print quality, wire handling automation and downstream manufacturing processes are considered. The latest developments are presented, including the direct bar code marking of wires, which for the first time offers reliable access to a full range of manufacturing data via machine readable code.

Computer-aided engineering (CAE) is a routinely used technology for the design and testing of road vehicles, including the simulation of their response to an impact. To increase automotive industry competitiveness by reducing physical test-based type approval and to improve road safety, recent initiatives have been taken by both industry and public authorities to promote the use of virtual testing through numerical simulation as an alternative way to check regulatory compliance. [1] To ensure acceptance of this alternative method, the accuracy of the simulation models and procedures needs to be assured and rated independently of the modelling process, software tools, and computing platform. Similarly, it is also imperative to understand the uncertainties emerging out of different component design parameters and analyze their sensitivity towards producing deviations in the reported results as per the requirements of the regulatory standard.

In this paper the effects of a rough underbody on the rear wake structure of a simplified squareback model (the Windsor model) is investigated using balance measurements, base pressure measurements and two and three component planar PIV. The work forms part of a larger study to develop understanding of the mechanisms that influence overall base pressure and hence the resulting aerodynamic drag. In the work reported in this paper the impact of a rough underbody on the base pressure and wake flow structures is quantified at three different ground clearances. The underbody roughness has been created through the addition of five roughness strips to the underbody of the model and the effects on the wake at ground clearances of 10.3%, 17.3% and 24.2% of the model height are assessed. All work has been carried out in the Loughborough University Large Wind Tunnel with a ¼ scale model giving a blockage ratio of 4.4% for a smooth under-body or 4.5% with the maximum thickness roughness strips.

This paper presents an examination of the impact of vehicle boundary conditions on future multiplexed vehicle signal & energy distribution systems. Boundary conditions ore discussed including requirements for: l)circuit protection 2) function isolation 3) option flexibility 4) distributed input and load hardware 5) reliability 6) redundancy 7) cost effectiveness 8) diagnosability 9) assembleability and, 10) B+ and ground distribution Based on these boundary conditions, an evaluation is made of both electrical and optical multiplex systems. Different configurations are examined such as: 1) centralized load control, 2) distributed load control, 3) single ring, and 4) multiple ring. Parameters which relate to wiring system cost, complexity, and reliability are considered.

Cold weather tests have been conducted on various engine components to monitor their operational modes at differing ambient temperatures. The results presented in this paper provide insight into the influence these components have on characteristic exhaust emissions at low ambient temperatures. In addition, atmospheric pollution levels have been monitored in general across Canada and specifically by the City of Toronto, Ontario, which indicate that seasonally these levels do not increase in cold weather. This is contradictory to the motor vehicle emission performance. Reasons for this apparent contradiction are expressed in this paper.

Vehicle front end air flow management affects many aspects of vehicle aero/thermal performances. The HVAC system capacity is greatly driven by the airflow and the air temperature received at the condenser. In this paper, front end design practices are investigated using computer simulation and full vehicle test to evaluate their effects on AC system performance. A full vehicle 3D CFD model is developed and used to predict the airflow and temperature in underhood and around the vehicle body, and specifically the conditions entering the condenser. The condenser inlet airflow and temperature profiles from 3D CFD model are then used as inputs for the 1D AC system model. The 1D AC system model, which includes condenser, compressor, evaporator and TXV (Thermal eXpansion Valve), is developed to observe the critical AC performance indicators such as panel out air temperature and compressor head pressure.

Heavy-duty electric powertrains provide a potential solution to the high emissions and low fuel economy of trucks, buses, and other heavy-duty vehicles. However, the high-capacity batteries needed to power these vehicles are both cost and weight prohibitive. One possible method of supplementing battery power is to mount flexible solar panel modules to the roof of these vehicles, thereby allowing for a smaller battery (reducing battery cost and weight) or extended vehicle range. Electric buses identified as the type of vehicle that would derive the most benefit from roof-mounted solar panels due to their low operating speed (including frequent idling) and large available surface area. In this paper, the performance of an electric bus with combined battery and photovoltaic power sources is simulated on the Orange County Bus Cycle for average weather in Davis, CA.

Plug-in Hybrid Electric Vehicles (PHEVs) are one of the main technology options for reducing vehicle CO2 emissions and helping vehicle manufacturers (OEMs) to meet the CO2 targets set by different Governments from all around the world. In Europe OEMs have introduced a number of PHEV models to meet their CO2 target of 95 g/km for passenger cars set for the year 2021. Fuel consumption (FC) and CO2 emissions from PHEVs, however, strongly depend on the way they are used and on the frequency with which their battery is charged by the user. Studies have indeed revealed that in real life, with poor charging behavior from users, PHEV FC is equivalent to that of conventional vehicles, and in some cases higher, due to the increased mass and the need to keep the battery at a certain charging level.

The intent of this research is to understand the effects worn dampers have on vehicle stability and safety through dynamic model simulation. Dampers, an integral component of a vehicle's suspension system, play an important role in isolating road disturbances from the driver by controlling the motions of the sprung and unsprung masses. This paper will show that a decrease in damping leads to excessive body motions and a potentially unstable vehicle. The concept of poor damping affecting vehicle stability is well established through linear models. The next step is to extend this concept for non-linear models. This is accomplished through creating a vehicle simulation model and executing several driving maneuvers with various damper characteristics. The damper models used in this study are based on splines representing peak force versus velocity relationships.

A previous study by the authors has shown an efficiency benefit of up to Δηi = 10 % for stratified operation of a high pressure natural gas direct injection (DI) spark ignition (SI) engine compared to the homogeneous stoichiometric operation with port fuel injection (PFI). While best efficiencies appeared at extremely lean operation at λ = 3.2, minimum HC emissions were found at λ = 2. The increasing HC emissions and narrow ignition time frames in the extremely lean stratified operation have given the need for a detailed analysis. To further investigate the mixture formation and flame propagation und these conditions, an optically accessible single-cylinder engine was used. The mixture formation and the flame luminosity have been investigated in two perpendicular planes inside the combustion chamber.

One of the most promising of the innovative transportation systems being proposed to alleviate problems caused by constantly increasing travel demands in urban areas is a dual-mode vehicle system. In such a system, automobiles are modified so that they may be operated under automatic control on certain specially constructed guideways in an urban area. This system combines the advantages of the line haul capabilities of an automated system with the distribution capabilities of the individually operated automobile. In this report, the results of a study aimed at determining expected volumes on a typical dual-mode network in the Detroit area as well as determining the impact of a dual-mode system on traffic conditions in the region are presented. Trip matrices were obtained from data supplied by the Detroit Regional Transportation and Land Use Study (TALUS), and state-of-the-art traffic assignment techniques were used to assign trips to the network.

In-cylinder flow and combustion processes simulated with the standard k-ε turbulence model and with an alternative model-employing a non-linear, quadratic equation for the turbulent stresses-are contrasted for both motored and fired engine operation at two loads. For motored operation, the differences observed in the predictions of mean flow development are small and do not emerge until expansion. Larger differences are found in the spatial distribution and magnitude of turbulent kinetic energy. The non-linear model generally predicts lower energy levels and larger turbulent time scales. With fuel injection and combustion, significant differences in flow structure and in the spatial distribution of soot are predicted by the two models. The models also predict considerably different combustion efficiencies and NOx emissions.

With the constant increase of fossil fuel prices and resources depletion, the researchers look beyond the usual alternative fuels for diesel engines. A lot of research is going on the employment of plastic polymers as fuels since they have a high potential to reduce diesel oil consumption and many of the aspects of their operation in diesel engines are not clarified yet. The major advantage of plastic polymers is the high calorific value, a widespread availability, and lower prices if they come from recycling. The paper presents the results from the research on a novel polyethylene blended diesel fuel and its use as alternative fuel for combustion in diesel generation plants. The authors investigated the formulation, injection, combustion and emissions of a new polyethylene-diesel fuel, obtained by an original process. The low density polyethylene (LDPE) has been mixed 5-40% by wt. with diesel by a new technology at 200 deg.

The effect on general aviation (GA) pilots' abilities to fly a small airplane while using a prototype data-linked weather information system (WIS) display, located in various cockpit positions, was investigated in comparison to the effect on their flying of acquiring weather information through conventional means. Ten GA pilots performed en route flying tasks of varying difficulty while concurrently performing weather information acquisition tasks. Pilots' subjective workload ratings, weather information acquisition times and accuracy levels, and preliminary flight path parameter deviation data indicate that using a WIS display results in smaller flight path parameter deviations, lower workload, and faster and slightly more accurate information retrieval than when weather information is obtained via the radio.

John Deere has introduced a new C-Series Construction Crawler which features an electronically-controlled dual-path hydrostatic transmission. This paper discusses the increase in performance, the improvement in operator controllability, the reduction in operator lever efforts, and the impact on manufacturing that is associated with the electronic controls. Comparisons are drawn between the C-Series Crawler and the previous model and to conventional power-shift torque converter crawlers.

Technological progress opens the door for the development of new tools to be used for the development of vehicles and engines. This offers the opportunity for an optimization of the entire workflow on one hand, and an improvement of single tasks on the other hand. This paper describes the actual status of the development process, describes new directions of tool evolvement and finally gives an outlook into the future. Redline ADAPT-SIM is a tool for driver- and vehicle simulation, which was developed primarily for ECU application, but can also be used for other dynamic testing tasks. The introduction of this tool leads to better controllability and therefore also repeatability of tests.

The safety, reliability and efficiency in the progress of the autonomous vehicle have increased in recent years. In parallel, companies in the segment of people transportation, either individually or shared, took the world leadership using smartphone app into a new concept of urban mobility with conventional vehicles with drivers, starting consequently a change of habit of the population, and defying the laws of local transport. These services for urban mobility are related as tendencies of driving forces in the face of the relevance of the limitations of resources, population density, greater awareness toward the environment and traffic congestion. The acquisition of the “own vehicle” as currently, conceived and successful by Alfred Sloan in the 1920s, has become a question for future generations.

The main objective of this work is to show a broad view of Digital Human Modeling software as a tool for aiding interior design projects for aircrafts. This will be achieved by showing digital manikins and their use during the development project of an aircraft interior. The time allocated to the design stage could be shortened and the costs concerning mock-up fabrication and certification were lowered because of this program's application during the entire process. The influence can be noted because of the ease to study monuments on high-density configurations, usability and accessibility of the door handles and on-board attendant visibility, etc. This paper is merely conceptual and do not involve existing aircrafts data or in development.

The share of hybrid and electric powertrains in the market increases continuously. In local driving conditions, electric vehicles are zero-emission, yet their regular use requires an infrastructure allowing the recharging of high-voltage batteries. Hybrid vehicles also allow the use of the electric drive; however, when the high-voltage battery is low, a combustion engine is used to recharge it. Hybrid powertrains do not require any changes in the infrastructure, nor do they force any changes in the driver's habits. The use of a hybrid vehicle may, however, reduce the operating time of the combustion engine, thus contributing to the reduction of fuel consumption. This reduction of fuel consumption results from a specifically selected energy flow strategy in hybrid systems. This strategy was the focus of the research performed to identify the energy flow conditions in a hybrid drive system under driving conditions corresponding to the RDE test.