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Plastic tailgates are described : thermosets as well as thermoplastic, dismantable or non dismantable, paintedor unpainted, stiffened by metallic parts or not … Some help to choose the good material is given, depending on the application and the specifications of the tailgate. Finally, examples of the use of such materials are given showing parts which answer the specifications, and showing also innovations being possible thanks to the use of such materials.

Fuel Cells: The most appropriate power source for the future. New systems and new material opportunities remain critical to the success of the program…BMC…a key material alternative.

The emission standards compliance is really becoming effective generally for all the class of engines and particularly for two-stroke SI. While for larger capacity and more valuable applications, such as scooters, snowmobiles, marine engines, the state of the art appears consolidated with the use of direct fuel injection systems, the engines dedicated to very light and simple applications need a different approach in terms of simplicity and cost. Aiming in this direction a system including a self - sustained air injection system in the exhaust and oxidation catalysts was prepared. The influence of the main design parameters governing the system performances and their mathematical relationships were experimentally studied with the aid of a DOE (Design of Experiment) technique methodology.

This paper presents the results and conclusions from a conceptual design study for a stratified charging concept. The stratified charging engine has a displacement of 64 cm3 and a four-port design with reed valves at two ports to control the bypass air. During the intake stroke of the engine, bypass air is sucked into the transfer ports to purge the air-fuel mixture present in the ports from the previous stroke back into the crankcase. This fills the transfer ports near the exhaust with pure air at the beginning of the scavenging stroke. During scavenging, the bypass air is ejected in the cylinder, shielding the exhaust against the fresh mixture coming from the ports on the intake side. This allows the hydrocarbon emissions to be reduced by over 40 %. The conceptual design study is based on an analysis of the mixture short-circuiting mechanisms and CFD investigations of the scavenging flow with charge stratification.

Once the focus of intense engineering scrutiny in the early 1990's, the major automotive companies suspended activity on 2-stroke engines because of perceived concerns over mechanical and emissions durability, and uncertain customer market acceptance. A 100-vehicle fleet, powered by the Orbital Combustion Process (OCP) air-assist direct fuel injected 2-stroke automotive engine, was launched into the Australian market to answer these questions. Homologated to Australian Design Rule (ADR) standards, the 2-stroke equipped vehicle fleet was distributed Australia-wide and exposed to a diverse range of driving styles and environmental conditions. Over three years, the Genesis ECOsport vehicles accumulated collectively in excess of 5.5 million kilometres with individual vehicles exceeding 160,000 km (or 100,000 miles). A brief overview will be given into the engine design, development and validation programs as well as vehicle build, validation, fleet management and data collection.

In October 1998, a new mass-produced car with titanium engine-valves was released from TOYOTA Motor Corporation. Both intake and exhaust valves were manufactured via a newly developed cost-effective P/M forging process. Furthermore, the material which was specially designed for the exhaust one is a unique titanium metal matrix composite (MMC). This paper discusses the materials and manufacturing methods used. The tensile, fatigue strength and creep resistance of the MMC are always superior to those for the typical heat-resistant steel of 21-4N. Both valves have achieved sufficient durability and reliability with a manufacturing cost acceptable for mass-produced automobile parts.

Currently there are three different types of bore solutions for small engines. 1) High silicon aluminum running with cast iron piston rings and a coated piston 2) Cast iron liner fitted to an aluminum block or cylinder 3) Nickel composite coating on an aluminum liner, cylinder, or block. A new method and apparatus has been developed to reduce the manufacturing tasks and costs of a bore solution. This method serves to produce a finished liner that can be installed into a block or cylinder, with less energy and fewer steps. This new method involves turning a liner from aluminum and coating with nickel-silicon carbide. For the finish honing, an apparatus was developed that enables a liner to be honed for interference or clearance bonded fit into the block or the cylinder. This paper is divided into two parts. The first part addresses the manufacturing and installation of liners and the second part gives engine designers some specifics of nickel ceramic composite electrolytic coatings.

In order to meet future emission standards of small two-stroke engines (CARB 2), detailed knowledge of in-cylinder charge motion and mixture distribution is essential to be able to provide new ways of reducing exhaust emissions. The aim is to minimize fuel short circuiting accompanying the scavenging flow, which in turn leads to high HC emissions. Therefore, an experimental investigation was carried out to investigate the in-cylinder flow structure during the gas exchange process inside a small two-stroke engine. An optically accessible cylinder was fitted to a 64 cm3 two-stroke engine and the transient gas motion examined with Particle-Image-Velocimetry (PIV) under a variety of operating conditions and speeds up to 6000 rpm. The flow was investigated in two vertical cross- sectional planes through the cylinder and in a horizontal plane. The flow was observed through endoscopic optics to overcome the limitations associated with the design of an optical aperture in the small engine.

This paper describes a simulation procedure to calculate a torque converter performance. The study focuses the validity of a solution and the handiness of the procedure. A comparison of the numerical solution and the experimental solution proves the model validity. Moreover, handiness is achieved by using commercial code with automatic unstructured mesh generating techniques. With suggested procedure, a complete analysis is carried out relatively fast. And an steady state interaction can be analyzed between three moving elements.

The power of two-stroke engine is influenced by the scavenging efficiency. Matching in-cylinder swirl ratio for injection system is indispensable. It is important to get low scavenging pressure to decrease mechanical power loss. This paper describes the effect of the scavenging ports configuration to the swirl ratio, the scavenging efficiency and the scavenging pressure, in case of uniflow scavenging two-stroke diesel engine that has four exhaust valves and the cylinder liner with scavenging ports. Especially we researched the relative advantages and disadvantages of shape factors using case-study by in-cylinder computational fluid dynamics simulation.

Conventionally, in automotive applications cooling pumps have been directly mechanically driven. This paper presents the significant improvements possible with their substitution by electrical cooling pumps A model of the thermal behaviour of the engine and of the cooling circuit has been developed. Two different configurations of the cooling system have been considered, the conventional one and one with an electrical cooling pump and an electrical operated bypass valve instead of the thermostat. Result of the modeling is a fourth order system with additional delays. The coolant mass flow through the pump and the bypass valve position are inputs. A control for the electrical pump and the electrical valve is developed, which influences the cooling fluid temperature and the engine temperature, with the aim of reducing the fuel consumption and mechanical wear during cold start and part load operating conditions.

The stand alone oil to air (OTA) transmission cooling strategy provides improved transmission cooling under high ambient air temperature operating conditions, which improves transmission reliability, durability and overall customer satisfaction. Another means of improving reliability and durability is through improved transmission warmup under low ambient air temperature operating conditions. To allow for improved transmission warmup, a thermostatic cold flow bypass valve has been incorporated into the transmission oil cooler. The bypass valve shuts off flow to the transmission oil cooler until a predetermined fluid temperature has been achieved. Once this temperature is reached, oil is allowed to flow to the transmission oil cooler. Visteon Climate Control Systems (VCCS) has tested both the stand alone OTA transmission cooling strategy with thermostatic cold flow bypass valve and the conventional transmission cooling strategy, comparing the transmission system warmup rates.

This study shows the measurement and calculation of exhaust heat exchange coefficient in a pipe of internal combustion engine. A specific exhaust-air heat exchanger has been installed on the exhaust line of engine. The Nusselt-Reynolds correlation has been developed and compared to the steady state conditions. The Convective Augmentation Factor (CAF) is approximately 2 at low Reynolds number and 1 at high Reynolds number. The EGR cooler and the exhaust-coolant heat exchanger for improving the passenger compartment heating have been shown.

Euro4 and EPA/02 emission regulations for the European and North American Heavy Duty truck market will require development of high efficiency, low pollution diesel engines. Informations received from main engine, truck manufacturers and literature surveys performed during the past two years shows that several technical solutions are being evaluated in order to reach the required emission levels. These technical solutions can be divided into 3 main groups: 1 Further optimization of fuel combustion including: increase of air to fuel ratio, further retardation of fuel injection timing. 2 Cooled EGR including: high recycled exhaust gas ratios, short EGR loop, compressed and aftercooled EGR. 3 Exhaust gas aftertreatment including: de-NOx catalysts, particle traps, particle afterburning. Different technical solutions will have different impacts on the heat rejection requirements and consequently on the layout and costs of the future cooling systems.

In this paper, a parameter to quantify the cyclic variability in first stages of combustion is presented, as an evolution of the parameter proposed by Hill and Kapil. This parameter relates the mean time necessary for the initial flame to reach the periphery of a turbulence eddy structure moving from the flame kernel position. This parameter is used in combination with quasi-dimensional models in order to predict and analyze small-scale turbulence contribution to cyclic variations. The cyclic dispersion parameter could be introduced in the predictive models as a delay in the combustion beginning. The parameter is compared with the experimental standard deviations in mass burned fraction at spark time obtained from others researchers works and own experimental data. A satisfying agreement between predictions and measurements is achieved.

Sound propagation within high temperature hydrocarbon combustion product was considered. Different methods for calculating sound speed within chemically reacting gas mixture were reviewed. One dimensional sound propagation was assumed. Results obtained using all these methods were presented. The results were compared and it was shown how error could be generated if inappropriate model is used for acoustic analysis in a chemically reactive gas mixture.

A one-dimensional model has been developed for the species and energy transfer over a thin (0.1-0.5 mm) layer of liquid fuel present on the wall of a spark-ignition engine. Time-varying boundary conditions during compression and flame passage were used to determine the rate of methanol vaporization and oxidation over a mid-speed, mid-load cycle, as a function of wall temperature. The heat of vaporization and the boiling point of the fuel were varied about a baseline to determine the effect of these characteristics, at a fixed operating point and lean conditions (ϕ = 0.9). The calculations show that the evaporation of fuels from layers on cold walls starts during flame passage, peaking a few milliseconds later, and continuing through the exhaust phase.

In spark ignition engines, the mechanism of transferring electrical energy from an ignition system into the mixture in the spark gap is controlled by many aspects. The major parameters of these aspects are inputs of electrical energy, combustion energy release, and heat transfers. Heat caused by combustion energy is transferred to the spark plug, cylinder head, unburned mixture, and others. This study presents the development and validation of a flame kernel initiation and propagation model in SI engines, and most of the aspects described above are considered during the course of the model development. Furthermore, the model also takes into account the strain rate of the initial kernel and residual gas fraction. The model is validated by the engine experiments, which are conducted in a constant volume combustion chamber.

Understanding lubrication failures at the shoe/swashplate contact of automotive swashplate compressors will greatly enhance the reliability of the air conditioning system. Maintaining proper lubrication is not always possible during transient conditions. Therefore, a method for detection of lubricant loss is of great interest to the automotive industry. Three methods for detecting lubrication loss were examined: contact resistance, acoustic emission, and dynamic pressure oscillations. A mobile air conditioning test stand capable of recording many system parameters was used. Oil return to the compressor was monitored using an oil separator and a refrigerant/oil concentration sensor. Data were taken during steady oil return rates and after oil shut off. The electrical contact resistance between the shoe and swashplate was used to indicate changes in the lubrication conditions at this critical interface. Measurements were taken at two oil return rates during steady oil return tests.

Optimization of vehicle air conditioning performance at various drive cycles and ambient conditions can be achieved by regulating and distributing the refrigerant flow entering evaporators. Thermostatic expansion valve (TXV), as a flow control device, has been a key element in improving vehicle A/C system operating efficiency and maximizing cooling capacity. Three scenarios are addressed in this paper: (a) the selection of TXVs for a sports utility vehicle (SUV) climate control system, in which a front HVAC unit and an auxiliary HVAC unit are installed; (b) the methodology of developing a goal-oriented criterion for identifying the TXV combination to fulfill the optimization of A/C system performance; and (c) the analytical and experimental evaluation of vehicle cooling performance by varying TXV combinations in various vehicle operating modes.