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The conventional Diesel cycles engine is now approaching the practical limits of efficiency. The recuperated split cycle engine is an alternative cycle with the potential to achieve higher efficiencies than could be achieved using a conventional engine cycle. In a split cycle engine, the compression and combustion strokes are performed in separate chambers. This enables direct cooling of the compression cylinder reducing compression work, intra cycle heat recovery and low heat rejection expansion. Previously reported analysis has shown that brake efficiencies approaching 60% are attainable, representing a 33% improvement over current advanced heavy duty diesel engine. However, the achievement of complete, stable, compression ignited combustion has remained elusive to date.

Brazil has a fleet with more than 30 million vehicles of combustion engine, lights and rides, riding for all territory, with a rate of 2 million sold per year. With this increased of fleet, specially from the end of 1990s, promoted principally by automobile factories that had come to Brazil and by circumstantial changes on the internal economy, some problems happened. The main problems are mobility difficulties on large cities (as traffic jams) and the environmental impacts (resources depletion, climate changes, issues of greenhouse effect gases, air pollution, acidification, waste generation, among others). Beyond that, in function of an inexistent national program and an undefined and unclear policy, there are uncountable (and potential) number of vehicles that could be sent to recycling processes, contributing to closed looping as raw material of new vehicles.

The recycling and reclamation of metal-matrix composites (MMC's) are critical aspects of the commercialization process. By recycling, we mean the economic processing of MMC scrap for reuse as composite. Reclamation refers to the separation and recovery of the individual components of the composite, i.e., the various aluminum alloys and ceramic particles. Three forms of MMC wrought alloy scrap have been considered; i.e., D. C. (direct chill) cast log ends, extrusion butts, and cut extrusion scrap. Recycling each of these forms of scrap back into D. C. cast extrusion billet has been demonstrated. This has been accomplished by recycling the scrap back through the basic mixing process. Various ratios of scrap to virgin composite have been explored and optimum blends are being studied. Similarly, for MMC foundry alloy (high silicon) gates and risers produced in shape-casting, fluxing and degassing techniques have been developed so these may be recycled back into useful castings.

Under the concern for the global environmental protection, recycle has also been remarked to be established. A lot of research and technology development have also been carried out for recycle on the world wide bases. Regarding the automotive recycle, although metals, especially steel, has already been collected and recycled as the steel scrap, other materials such as plastics and catalyst platinum are considered to be recycled as well. As a part of the automotive plastic recycle, “With paint recycle technology” for “In line painted Noryl GTX6011 bumper which is made of PPE/PA alloy by GE Plastics has been achieved by Nissan Shatai Co and GE Plastics. “With paint” recycle is a recycle of the painted plastic automotive parts for the painted parts without removing of the paint. Conventionally, paint removal has been considered to be inevitable in the painted polyolefinic bumper recycle.

Numerous studies have demonstrated that exhaust gas recirculation (EGR) can attenuate knock propensity in spark ignition (SI) engines at naturally aspirated or lightly boosted conditions [1]. In this study, we investigate the role of cooled EGR under higher load conditions with multiple fuel compositions, where highly retarded combustion phasing typical of modern SI engines was used. It was found that under these conditions, EGR attenuation of knock is greatly reduced, where EGR doesn’t allow significant combustion phasing advance as it does under lighter load conditions. Detailed combustion analysis shows that when EGR is added, the polytropic coefficient increases causing the compressive pressure and temperature to increase. At sufficiently highly boosted conditions, the increase in polytropic coefficient and additional trapped mass from EGR can sufficiently reduce fuel ignition delay to overcome knock attenuation effects.

Although water injection or water/fuel emulsions are a well known method of reducing NOx in stationary Diesel engines, their influence on Diesel particulates and particulate SOF has recieved little study. A single cylinder DI Petter engine was used to investigate the influence of Diesel/water emulsions on particulate emissions and associated gaseous emissions. Water/fuel ratios of up to 20% were used and a strong influence on emissions was found. Both NOx and particulate emissions were decreased with increased water content. However, there was a major increase in the unburnt hydrocarbons. Associated with this was a similar increase in the particulate solvent organic fraction and of the PAH fraction of this. These effects on UHC and PAH emissions make Diesel/fuel emulsions an unattractive solution to the Diesel NOx and particulate emissions problems.

Reduced engine noise has contributed greatly to the comfort of today's passenger vehicles. Despite the increased use of computer-aided engineering (CAE) tools for acoustical simulation, experimental methods continue to play an important role in the reduction of engine noise. Experimental methods have been developed and tested in order to standardize the procedure by which acoustical radiation can be attenuated and assure the accuracy of the results.

A PREVIOUS PAPER (1*), reported on fuel consumption reductions achieved, by the use of a Regenerative Power Train system, applied to a city bus. An overall fuel economy gain of 20% was obtained previously, on the track, when operating the bus on the City Business District cycle (2) [CBD cycle, 20 mph maximum speed and 7 stops per mile], and a similar 30 mph cycle. The results reported here, were obtained using a CBD type driving cycle and indicate the extent of the reductions in regulated diesel exhaust emissions, achievable with a Regenerative Power Train. NOx was reduced 19 percent somewhat in line with the percentage improvement in fuel economy; particulate and CO emissions were more strongly influenced, with reductions of 27 and 60 per cent, respectively. HC emissions were the least affected with a reduction of 8 percent.

The paper represents a distillation and analysis of collision injury cases collected by the UCLA Trauma Research Group from 1960-1969. Injuries are interpreted with relation to specific variables which are thought to represent important factors in collision injury causation and prevention. The methodology is presented as one possible way to view transportation trauma in terms of factors which can be isolated and may lend themselves to manipulation in the cause of traffic safety.

To reduce emissions from diesel engines, the effects of oxidation catalysts on the emissions reductions were studied. The effectiveness of several oxidation catalysts on both the regulated and unregulated emissions was evaluated. The oxidation activity of the catalysts was varied by changing Pt loading. The regulated emissions include particulate (PM), hydrocarbon (HC), and carbon monoxide (CO), and the unregulated emissions include benzene, formaldehyde, acetaldehyde, and benzo[a]pyrene (B[a]P). An 8 litter, turbocharged and aftercooled diesel engine was operated under the Japan Diesel 13 (D13) mode cycle for the evaluations. As the first step, evaluations were conducted with a commercially available JIS #2 diesel fuel (0.046 wt% sulfur). All the regulated and unregulated emissions except PM were reduced as the Pt loading (i.e. oxidation activity) increased. However, PM emissions were increased by the generation of sulfate when the Pt loading exceeded 0.2 g/l.

The benefits of applying thermal insulation to the exhaust ports and combustion chamber components are predicted using a computer simulation of a highly rated turbocharged DI diesel truck engine. Comparisons are made between a standard engine and engines with the exhaust port, cylinder head, piston and cylinder liner insulated individually or in combination. The necessity of re-optimizing engine conditions when heat losses through the combustion chamber walls are significantly changed is also examined. The importance is recognized of developing techniques of reducing heat losses to the engine cooling system which can be applied at low cost and with minimal changes to existing engine designs. Potential methods of achieving these objectives are reviewed and their effectiveness assessed. This paper also describes the successful testing of a ceramic liner located in the exhaust duct of a diesel engine during more than 1000 hours of engine operation.

The paper describes the detailed crash investigation of rear underrun crashes, including occupant injuries; the development of theoretical analysis of the forces acting on a barrier during an impact from a car; and the design, development and crash testing of an effective barrier. One aim of the project was to demonstrate that an effective, lightweight and inexpensive barrier can be fitted to the rear of trucks. These findings were compared with existing design standards for rear underrun barriers and significantly upgraded performance requirements were recommended to be adopted as a new standard for Australia.

Mechanical load and thermal load are the two main barriers limiting the engine power output of heavy duty (HD) diesel engines. Usually, the peak cylinder pressure could be reduced by retarding combustion phasing while introducing the drawback of higher thermal load and exhaust temperature. In this paper, Miller cycle with late intake valve closing was investigated at high speed high load condition (77 kW/L) on a single cylinder HD diesel engine. The results showed the simultaneous reduction of mechanical and thermal loads. In the meanwhile, higher boosting pressure was required to compensate the Miller loss of the intake charge during intake and compression process. The combustion temperature, cylinder pressure, exhaust temperature and NOx emission were reduced significantly with Miller cycle at the operating condition. Furthermore, the combustion process, smoke number and fuel consumption were analysed.

Noise level results for a range of types of truck tire tread patterns and road surfaces are discussed. Some of the results of noise level in dry conditions are related to braking grip in wet conditions, showing that it is possible to increase wet grip and still reduce noise level. Computer studies using the mechanical frequency modulation method of predicting dominant tread pattern frequencies from tread segment pitch variations are dealt with including an automatic optimization procedure. A further development which includes the detail of the tread pattern in the segment as input to the computer gives closer prediction of higher harmonics of more complex tread patterns. Recent tests on total traffic noise after resurfacing the Hammersmith fly-over in London, England, have shown almost a 3dB(A) reduction with Delugrip Road Surfacing Material compared with the original British Standard Hot Rolled Asphalt.

THE elimination of wear of piston-rings and cylinders can be the ultimate goal toward which to strive but, in reaching this Utopia if it can be reached, the most practical road seems to be by way of wear reduction. Many factors indicate the necessity for a “wear-in” period. At some point in service wear-in ceases and “wear-out” starts. As wear-in takes place, performance only improves to a certain point and, from there on, piston-rings and cylinders can be considered as wearing out. The rubbing action of a piston-ring on a cylinder wall breaks particles loose from the surfaces that act as an abrasive. This breakdown of the rubbing surfaces, regenerative because of the abrasive action of the resulting loose material, causes wear. The ease with which the surface of a material will break down and the physical characteristics of the loose particles so produced are indicated to a great extent by structure. The structure of a material is therefore an indication of expected wear.

The performance and emissions of a medium duty, turbocharged and aftercooled diesel engine fitted with both standard pistons and experimental pistons have been compared. The experimental pistons incorporated micro-chambers equi-spaced around the periphery of the bowl, connected to the bowl by drilled passages. The tests were run using an “A-B-A” design at three engine speeds over the load range. The paper will report that the experimental pistons have a potential for significant soot reduction without an increase in NOx emissions and with similar fuel consumption. Based on an analysis of the jet flow into and out of the micro-chambers, a possible mechanism for the soot reduction is proposed. The mechanism has been investigated further using VECTIS computational fluid dynamics (CFD) analysis.

The main end of this research is the optimization of engine sub-frame parameters in a passenger car to reduce the transmitted vibration to vehicle cabin through DOE method. First, the full vehicle model of passenger car including all its sub-systems such as engine, suspension and steering system is modeled in ADAMS/CAR and its accuracy is validated by exerting swept sine and step input. After that, the schematic geometry of sub-frame is modeled in CAD software and transferred to ADAMS/CAR. Hence, the efficiency of the sub-frame in terms of reducing the induced vibration to vehicle cabin is examined through the various road inputs e.g. swept sine, step and random road input type (B). The results will illustrate that the sub-frame has significant effect in reduction of transmitted vibration to occupants. In order to optimize the sub-frame parameters, the sensitivity analysis is performed to derive effective parameters of sub-frame using DOE method.

EADS SPACE Transportation has developed and qualified under ESA contract the Refrigerator/Freezer Rack (RFR) for use by NASA on-board the ISS. This paper will present a general overview of the RFR system design, the qualification test results and an outlook to potential future usage of the RFR.

Currently a Refrigerator/Freezer Rack (RFR) for theInternational Space Station (ISS) is developed by Daimler-Chrysler Aerospace. The Refrigerator/Freezer System consisting of a pool of 10 flight racks in total, with a 3 racks complement always on-orbit, will provide the necessary conditioned volume for the crew’s frozen and refrigerated food as well as for other cargo items requiring conditioned stowage. The Mini Pressurized Logistics Module (MPLM) will be utilized for upand download logistics. Either the racks or the cargo only will be swapped from the MPLM to the ISS and back again. In the following section the preliminary RFR design concept as a result of a Phase A study will be presented.