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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.

The gasoline direct injection (GDI) engine particulate emission sources are assessed under cold start conditions: the fast idle and speed/load combinations representative of the 1st acceleration in the US FTP. The focus is on the accumulation mode particle number (PN) emission. The sources are non-fuel, combustion of the premixed charge, and liquid fuel film. The non-fuel emissions are measured by operating the engine with premixed methane/air or hydrogen/air. Then the PN level is substantially lower than what is obtained with normal GDI operation; thus non-fuel contribution to PN is small. When operating with stoichiometric premixed gasoline/air, the PN level is comparable to the non-fuel level; thus premixed-stoichiometric mixture combustion does not significantly generate particulates. For fuel rich premixed gasoline/air, PN increases dramatically when lambda is less than 0.7 to 0.8.

This paper quantifies the potential of electric propulsion systems to reduce petroleum use and greenhouse gas (GHG) emissions in the 2030 U.S. light-duty vehicle fleet. The propulsion systems under consideration include gasoline hybrid-electric vehicles (HEVs), plug-in hybrid vehicles (PHEVs), fuel-cell hybrid vehicles (FCVs), and battery-electric vehicles (BEVs). The performance and cost of key enabling technologies were extrapolated over a 25-30 year time horizon. These results were integrated with software simulations to model vehicle performance and tank-to-wheel energy consumption. Well-to-wheel energy and GHG emissions of future vehicle technologies were estimated by integrating the vehicle technology evaluation with assessments of different fuel pathways. The results show that, if vehicle size and performance remain constant at present-day levels, these electric propulsion systems can reduce or eliminate the transport sector's reliance on petroleum.

Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES. Past studies were reviewed in the light of today's technical advancement and a technology trade-off, supported by bread boarding, is performed. Current activities do concentrate on Critical technology selection and feasibility demonstration including bread boarding and testing, Methane Pyrolysis Assembly (MPA) operational interfaces with ARES Potential applications of MPA for other exploration capabilities, like in-situ resources utilization (Moon and Mars) The paper presents the achievements so far.

During the last years extensive work has been done to design and develop the Closed-Loop Air Revitalization System ARES. The potential of ARES e.g. as part of the ISS ECLSS is to significantly reduce the water upload demand and to increase the safety of the crew by reducing dependence on re-supply flights. The design is adapted to the interfaces of the new base lined Russian MLM module as possible location for a future installation of ARES. Due to the lack of orbital support equipment and interfaces to a waste water bus, to a feed water supply line and due to the availability of only one single vent line it was necessary to make the ARES process water loop as independent as possible from the host vehicle. Another optimization effort was to match the CO2 desorption profile with the available hydrogen flow to achieve a sufficient water recovery performance, while meeting all related safety requirements, minimizing complexity and improving reliability.

Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES, see figure 1. Past studies as presented in ref. /1/ had been reviewed in light of today's technical advancement and a technology trade-off, supported by bread boarding, resulting in the pre selection of the plasma technique to perform the Methane Pyrolysis. In parallel two methods for plasma provision are investigated: Direct Current Plasma, sustained by a discharge arc rotating in a nozzle to supply energy to the flowing through carrier gas. Micro Wave (MW) Plasma, sustained by a MW within a Quartz tube embedded in a MW resonator cuboid Study activities did concentrate on Development testing of pre selected plasma Pyrolysis technology.

European Space Agency's (ESA's) Columbus module was launched on February 7, 2008. This marks the completion of more than 10 years of development. It is a major step forward for Europe in the area of Environmental Control and Life Support (ECLS) as Columbus contains several major assemblies which have been developed in Europe. These include the Condensing Heat Exchanger, Condensate Water Separator and the Cabin Fans. The paper gives a short overview of the system and its features and it will report the experiences from the initial activation and operations phase.

The launch and activation of ESA's Columbus module in early 2008 marked the completion of more than 10 years of development. Since then the Columbus ECLS is operating, including its major European ECLSS assemblies such as Condensing Heat Exchanger (CHX), Condensate Water Separator, Cabin Fans and Sensors. The paper will report the experiences from the first year of operations in terms of events, failures and lessons learned. Examples of this is the description of some off-nominal situations (such as Condensate Removal and IMV Return Fan failure, and relevant troubleshooting), and the preparation to Columbus Reduced Condensation Mode, as requested by NASA in order to minimize the crew time needed to empty Condensate Water Tanks in US Lab.

Hydrogen can be readily used in spark-ignition engines as a clean alternative to fossil fuels. However, a larger burning velocity and a shorter quenching distance for hydrogen as compared with hydrocarbons bring a larger cooling loss from burning gas to the combustion-chamber wall. Because of the large cooling loss, the thermal efficiency of a hydrogen-fueled engine is sometimes lower than that of a conventionally fueled engine. Therefore, the reduction of the cooling loss is very important for improving the thermal efficiency in hydrogen-combustion engines. On the other hand, the direct-injection stratified charge can suppress knocking in spark-ignition engines at near stoichiometric overall mixture conditions. Because this is attributed to a leaner end gas, the stratification can lead to a lowered temperature of burning gas around the wall and a reduced cooling loss.

EADS SPACE Transportation investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES. Past studies are reviewed in the light of today's technical advancement and a technology trade-off, supported by breadboarding, is performed. Accordingly, current activities do concentrate on Critical technology selection and feasibility demonstration including breadboarding and testing, Methane Pyrolysis Assembly (MPA) operational interfaces with ARES Potential applications of MPA for other exploration capabilities, like in-situ resources utilization (Moon and Mars) The paper presents the achievements so far.

EADS SPACE Transportation GmbH designed, built and tested a condensate buffer to be located between a Condensing Heat Exchanger (CHX) and a Condensate Water Separator Assembly (CWSA), as part of the ECLSS of the European Columbus Module. Under zero-g conditions, the separation of water from an air-water mixture is always difficult, especially if a passive device is to be used such as the low power consuming Columbus CWSA. The additional buffer volume reduces condensate water peaks reaching the CWSA to a level that excludes an overloading of the CWSA and a release of free water droplets into the air return to the cabin. In the CHX/CWSA system this may only be necessary under worst case operational conditions and with a failure of the qualified hydrophilic coating of the CHX. The buffer design principle was confirmed via prior analyses and on-ground testing. The performance of such a condensate buffer under micro-g conditions was verified during parabolic flights.

The extent of oxidation of hydrocarbons desorbing from the oil layer has been measured directly in a hydrogen-fueled, spark-ignited engine in which the lubricant oil was doped with a single component hydrocarbon. The amount of hydrocarbon desorbed and oxidized could be measured simultaneously as the dopant was only source of carbon-containing species. The fraction oxidized was strongly dependent on engine load, hydrogen fuel-air ratio and dopant chemical reactivity, but only modestly dependent on spark timing and nitrogen dilution levels below 20 percent. Fast FID measurements at the cylinder exit showed that the surviving hydrocarbons emerge late in the exhaust stroke.

Given the constraints of the current launchers, manned exploration beyond LEO implies long time missions, a high mass of metabolic consumables and consequently regenerative life support technologies developments. To validate their efficiency, as well as their reliability, these technologies need to be tested in the most analog conditions (i.e. isolation, limited spare part, …). A large number of these conditions are met in the new permanent French-Italian settlement called Concordia, currently being built in the Antarctic continent. Over the last 15 years, ESA developed regenerative life support technologies. Two of these technologies: a Grey Water Treatment Unit and a Black Water Treatment Unit are currently assembled at the size of 15 to 70 persons to fulfill the Concordia crew needs The first technology is a multi step filtration system and will recycle the shower, washing machine, dish washer and cleaning water.

The use of hydrogen as a fuel supplement for lean-burn engines at higher compression ratios has been studied extensively in recent years, with good promise of performance and efficiency gains. With the advances in reformer technology, the use of a gaseous fuel stock, comprising of substantially higher fractions of hydrogen and other flammable reformate species, could provide additional improvements. This paper presents the performance and emission characteristics of a gas mixture of equal volumes of hydrogen, CO, and methane. It has recently been reported that this gas mixture can be produced by reforming of ethanol at comparatively low temperature, around 300C. Experiments were performed on a 1.8-liter passenger-car Nissan engine modified for single-cylinder operation. Special pistons were made so that compression ratios ranging from CR= 9.5 to 17 could be used. The lean limit was extended beyond twice stoichiometric (up to lambda=2.2).

MIT Lincoln Laboratory is tasked by the U.S. Federal Aviation Administration to investigate the use of the NEXRAD polarimetric radars* for the remote sensing of icing conditions hazardous to aircraft. A critical aspect of the investigation concerns validation that has relied upon commercial airline icing pilot reports and a dedicated campaign of in situ flights in winter storms. During the month of February in 2012 and 2013, the Convair-580 aircraft operated by the National Research Council of Canada was used for in situ validation of snowstorm characteristics under simultaneous observation by NEXRAD radars in Cleveland, Ohio and Buffalo, New York. The most anisotropic and easily distinguished winter targets to dual pol radar are ice crystals.

1 The Closed-Loop Air REvitalisation System ARES is a proof of technology Payload. The objective of ARES is to demonstrate with regenerative processes: the provision of the capability for carbon dioxide removal from the module atmosphere, the return supply of breathable oxygen within a closed-loop process, the conversion of the hydrogen, resulting from the oxygen generation via electrolysis, to water. The ARES Payload is foreseen to be installed - in 2012 - onboard the ISS in the Columbus Module. The operation of ARES - in a representative manned microgravity environment - will produce valuable operational data on a system which is based on technologies which are different from other air revitalization systems presently in use. The ARES Technology Demonstrator Payload development started in 2003 with a Phase B, see references [1], [2], [3] and [4]. ARES is presently in Phase C1 and a PDR is scheduled for the beginning of 2009.