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It has been found that over Rh/a specified support NOx is eliminated using rich/lean excursions in a different reaction mechanism from a Lean NOx Trap system, where NO is decomposed into nitrogen and oxygen. The contribution of the transient NOx direct decomposition to NOx elimination depends on both reaction conditions and supports. 0.1-0.5wt%Rh and 0.5wt%Pd/a specified support: X can mainly catalyze the transient NO decomposition. On the other hand, on another Rh-based catalyst NO reduction proceeds mainly in the Lean NOx trap system. As expected from the NO elimination mechanism, the newly developed catalyst has shown a high tolerance against SOx.

This paper presents a new transient passenger thermal comfort model. The model uses as inputs the vehicle environmental variables: air temperature, air velocity, relative humidity and mean radiant temperature all of which can vary as a function of time and space. The model also uses as inputs the clothing level and the initial physiological state of the body. The model then predicts as a function of time the physiological state of the body and an effective human thermal sensation response (e.g. cold, comfort, hot, etc.). The advantage of this model is that it can accurately predict the human thermal sensation response during transient vehicle warm-up and cooldown conditions. It also allows design engineers the ability to conduct parametric studies of climate control systems before hardware is available. Here we present the basis of the new thermal comfort model and its predictions for transient warm-up and cooldown conditions.

Engines equipped with pressure charging systems are more prone to knock partly due the increased intake temperature. Meanwhile, turbocharged engines when operating at high engine speeds and loads cannot fully utilize the exhaust energy as the wastegate is opened to prevent overboost. The turboexpansion concept thus is conceived to reduce the intake temperature by utilizing some otherwise unexploited exhaust energy. This concept can be applied to any turbocharged engines equipped with both a compressor and a turbine-like expander on the intake loop. The turbocharging system is designed to achieve maximum utilization of the exhaust energy, from which the intake charge is over-boosted. After the intercooler, the turbine-like expander expands the over-compressed intake charge to the required plenum pressure and reduces its temperature whilst recovering some energy through the connection to the crankshaft.

Twin-scroll turbine housing with divider wall in turbocharger promises to increase low-end torque, improve boost response and maximize turbine efficiency. This paper proposes a new twin-scroll turbine housing design. The unique design feature is first introduced. Numerical simulation which takes into account transient state film heat transfer convection, temperature-dependent strain hardening behavior and cyclic thermal loads are carried out for both traditional and the new design. Simulation results include temperature, stress and plastic strain at divider wall are compared and analyzed as well which indicate the new turbine housing has improved reliability at divider wall. This study reveals how to obtain a robust turbine housing divider wall and provides a knowledge base for the design and use of divider wall.

The design and development of a new four-stroke two-cylinder diesel engine family of 1.29 litre capacity for off road are discussed. The engine is in naturally aspirated and turbocharged and intercooled versions and rated from 11.9 kW/1500 rpm to 25.7 kW/2500 rpm. The engines were tuned for air and fuel flows, air utilisation, fuel air mixing, performance and emissions at steady state at a development lab and later certified in national labs. The high altitude capability of the TCIC was checked using a model. The engines rated at less than 19 kW satisfy India Generator set and off road norms of India and Europe equivalent to USTier4 standard, and at higher ratings, standard equivalent to US Tier4-interim. In the second part of the paper, the design of coolant and oil pumps, oil cooler for TCIC engine and the piston with steel oil control ring are discussed. The higher loaded TCIC engines use fillet hardened crankshafts of chromium molybdenum steel.

For large space structures (LSS), the interaction between control system and structural vibration is a major problem. In this paper, the authors will show a new two Degrees-of-Freedom actuator called “Super precision Positioning Device (SPD)” (1)∗ which converts rotational motion to translational motion without cams or link mechanism, and experimental results of active vibration control to large space structures using the actuator as an active damping enhancer. In the experiment, the SPD is mounted to a rigid base to which a flexible structure model is attached. The structure is a free standing flexible frame type structure and it has multi-dimensional vibration modes to simulate a real structure. The movement of the SPD is controlled to damp three dimensional vibration by sensing moments of the structure. The experimental results in this paper shows that the SPD is capable of reducing multi-dimensional structural vibration.

The two major working characteristics of the oil control ring are: to scrape the lubricant oil from the bore wall in the direction of the crankcase and to maintain a sufficient amount of lubricant oil to the compression rings above it in order to sustain a suitable lubricant film thickness between the rings and the bore. The oil control ring efficiency is the outcome of the combination of the following parameters: the conformability, the pressure against the bore wall, the sort of the contact between the ring and the bore, and the oil scraping dynamics. A new oil control ring, called Monoland®, designed to enhance conformability by making its radial wall more flexible without raising its tangential load is presented in this paper. Moreover, this new ring profile enables the reduction of the tangential load without reducing contact pressure and conformability thus ensuring an ample oil consumption performance with low friction loss.

A new concept for high efficiency two-stroke cycle spark-ignition engines has been developed. The installation of the IFP-developed pneumatic fuel injection process in a two-stroke engine allows the introduction of the fuel separately from the scavenging air, in order to minimize fuel shortcircuiting. The process does not require an external air pump since the compressed air used to atomize the fuel is supplied at no expense by the crankcase. The premixed charge is delivered directly into the cylinder with a high spray quality, its stratification for the optimization of combustion is controlled by a valve. This process, therefore, provides the advantages of the direct injection but uses commercially available gasoline injectors. A single-cylinder engine has been developed first to verify the potential of the process.

A unique electronically controlled fuel injection system, named ECI, has been developed for 2.0- and 2.6-liter passenger car gasoline engines. The system incorporates a vortex shedding airflow sensor, a single-point injection assembly, a microprocessor control unit and other peripheral devices. This paper presents descriptions of physical arrangement, system components and control strategy of the ECI system.

The authors have developed a new partial flow dilution tunnel (hereafter referred to as PPFT), whose principal device is a flux splitting gas divider, as a new means of measuring particulate emissions which can be applied to transient cycle testing of diesel engines. The advantage of this system is that it can achieve perfect constant velocity splitting by means of its structure, and theoretically can also maintain high splitting performance despite fluctuations in the exhaust flow rate, including those due to engine exhaust pulsation. We compared this system with a full tunnel by analyzing the basic performance of the system and measuring particulate matter (PM) using an actual vehicle engine.

This paper includes a brief description of present day rear axle designs and their bearings. It also includes a complete discussion of the design objectives of a new concept in single row tapered roller bearings and of the design features of this new bearing. The new bearing is preadjusted and carries thrust loads in either direction, as well as radial loads in any combination. A detailed discussion of its development and testing, both laboratory and field, is presented.

The earth's fossil energy is not limitless, and we should be taking advantage of the highly developed fields of science and technology to utilize it more efficiently and to create a fully environmentally friendly life. Considering the prodigious amount of vehicles in the world today, even a small improvement in their energy-saving performance could have a significant impact. In this paper, a new type of electro-hydraulic power steering (EHPS) system is described. It has two main advantages. First, it can significantly decrease the demand on the motor so that it can be used for a wider range of vehicles. Second, its pressure-flow characteristic can be programmed and is more flexible than hydraulic power steering (HPS) system. A prototype with a 500 W motor was applied to a truck with a front load of 2,700 kg, and static steer sweep tests were conducted to validate its feasibility.

Present-day trucking applications are increasing in complexity and placing an ever increasing demand on the truck engine to serve as the power source for operating a wide variety of auxiliary equipment. This equipment is demanding a high level of sophisticated speed control which must respond to greater requirements than simply speed governing. A speed control must be responsive to multiple input control signals and capable of operating at numerous speed levels automatically. This paper describes a recently developed speed control system consisting of a solid-state printed circuit control module coupled with an electrovacuum actuator. This system is responsive to present day flexibility and operational demands. It also offers features such as multilevel speed control, remote speed, load droop, and stability adjustment, monitoring feed back, and responsiveness to control signals from multiple stations.

A new type of sensor capable of sensing the direction and velocity of motion of smooth surfaced metallic targets is described. The sensor consists of a small permanent magnet and a magnetic field sensor displaced from each other along the line of motion, each at a small fixed distance from the target surface. Operation is based on the motion dependent location, strength and polarity of magnetic field sources created within proximate target regions via their passage through the field of the magnet. The fields arising from these target regions are detected by the magnetic field sensors, typically Hall effect or magnetoresistive devices. With ferromagnetic targets, a non-volatile memory of the direction of last occurring motion is also provided. Utility of these sensing capabilities is illustrated by descriptions of applications for automatic turn signal canceling and antitheft devices, back-up alarm activation and for engine misfire detection via crankshaft speed variation.

The Miller system proposed by Frank Miller was practiced in a high speed diesel engine by the combination of an additional rotary valve at the intake manifold and two stage turbo-chargers. The experimental result showed bmep boost at lower engine speed range and improvement in several performance characteristics, some of which might not be predicted in the original concept. Also the advantages and disadvantages of the rotary valve arrangement as a mean to practice intake air variable closing timing were studied. Taking all into consideration, it is concluded that this system is fairly effective and practical in realizing high bmep diesel engines.

This paper deals with a new type of Miller cycle engine which is installed with an intake control rotary valve, and presents the experimental investigation on the test engine which was undertaken to examine the capacity of supercharging as well as fuel economy in the application of the new system to small-sized gasoline engines. An experimental investigation on the test engine with some simple modification to a conventional engine revealed that the intake control rotary valve installation is quite effective to control the virtual compression ratio. It was ascertained by an external supercharging test that reduced compression ratio with constant expansion ratio allowed the test engine to obtain a considerably higher level of torque in the low engine speed range than had been attained in conventional supercharged engines without any increase in fuel consumption.

A unique “light” robot assembly cell, designed by the CTRI robotic division of DASSAULT AVIATION has been put in production in DASSAULT's Biarritz assembly plant. The designation “light” was chosen because it represents an alternative to either a heavy single purpose machine or a stiffer robotic system. The choice was made after a careful examination of the alternatives available and was based on the following hypothesis: a robotic cell, whose cost needs to be justified against a sub-contract opportunity of limited duration, must embody the following characteristics: 1) LOW COST in order to assure pay-back with the term of the subcontract 2) FLEXIBLE in order to accommodate future production requirements without major system modification. In order to meet these goals, we chose a standard low mass robot and provided it with a long track in order that it be able to cover a large work area at a minimum cost. The result was a very cost effective and efficient production system.

Silencers are a very effective way to reduce two of the most severe kinds of turbocharger noises, called “pulsation” noise and “blow” noise. PSA has developed its own silencer design based on a combination of a Herschel-Quincke tube and two quarter-wave resonators. The new device has a transmission loss of over 15 dB from 1600 to 3400 Hz. It will be first applied on the 2001 Peugeot 406 and Citroën C5.