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The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) *) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nano-particles counts (NP) were carried out.

This specification covers quality assurance sampling and testing procedures used to determine conformance to applicable material specifications of corrosion- and heat-resistant steel and alloy forgings.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

1 An all fiber-optic sensor has been developed to measure H2O mole fraction and gas temperature in an HCCI engine. This absorption-spectroscopy-based sensor utilizes a broad wavelength (1320 to 1380 nm) source (supercontinua generated by a microchip laser) and a series of fiber Bragg gratings (19 gratings centered on unique water absorption peaks) to track the formation and temperature of combustion water vapor. The spectral coverage of the system promises improved measurement accuracy over two-line diode-laser based systems. Meanwhile, the simplicity of the fiber Bragg grating chromatic dispersion approach significantly reduces the data reduction time and cost relative to previous supercontinuum-based sensors. The data provided by the system is expected to enhance studies of the chemical kinetics which govern HCCI ignition as well as HCCI modeling efforts.

A gasoline Road Octane study was conducted by the Coordinating Research Council (CRC) to evaluate the effects of heavy aromatics (C9 and heavier) and ethanol content on Road Octane performance independent of Research Octane Number (RON) and Motor Octane Number (MON). Maximum-throttle and part-throttle Road ON’s were found to be well predicted by equations containing only RON and MON terms. Heavier aromatics were found to have a small adverse effect on both maximum-throttle and part-throttle Road ON independent of its direct effects on RON and MON. The all-car data did not show a significant ethanol-content effect, but eight of the thirty-seven cars did show significant effects for ethanol content.

This paper deals with some recent advances in the field of 1D fluid dynamic modeling of unsteady reacting flows in complex s.i. engine pipe-systems, involving a catalytic converter. In particular, a numerical simulation code has been developed to allow the simulation of chemical reactions occurring in the catalyst, in order to predict the chemical specie concentration in the exhaust gas from the cylinder to the tailpipe outlet, passing through the catalytic converter. The composition of the exhaust gas, discharged by the cylinder and then flowing towards the converter, is calculated by means of a thermodynamic two-zone combustion model, including emission sub-models. The catalytic converter can be simulated by means of a 1D fluid dynamic and chemical approach, considering the laminar flow in each tiny channel of the substrate.

In this work a detailed model to simulate the transient behavior of catalytic converters is presented. The model is able to predict the unsteady and reacting flows in the exhaust ducts, by solving the system of conservation equations of mass, momentum, energy and transport of reacting chemical species. The en-gine and the intake system have not been included in the simulation, imposing the measured values of mass flow, gas temperature and chemical composition as a boundary condition at the inlet of the exhaust system. A detailed analysis of the diffusion stage triggering is proposed along with simplifications of the physics, finalized to the reduction of the calculation time. Submodels for water condensation and its following evaporation on the monolith surface have been taken into account as well as oxygen storage promoted by ceria oxides.

This work describes an experimental and numerical investigation of the thermal transient of i.c. engine exhaust systems. A prototype of exhaust system has been investigated during a NEDC cycle in two different configurations. Firstly an uncoated catalyst has been adopted to consider only the effect of the gas-wall heat transfer. The measurements have been repeated on the same exhaust system equipped with a coated catalyst to point out the contribution of the chemical reactions to the thermal transient of the system. The measured values have been compared to the predicted results carried out with a 1D thermo fluid dynamic code, developed in-house to account for the thermal transient of the system and the chemical reactions occurring in the catalyst.

This paper describes some recent advances of the research work concerning the 1D fluid dynamic modeling of unsteady reacting flows in s.i. engine pipe-systems, including pre-catalysts and main catalysts. The numerical model GASDYN developed in previous work has been further enhanced to enable the simulation of the catalyst. The main chemical reactions occurring in the wash-coat have been accounted in the model, considering the mass transfer between gas and solid phase. The oxidation of CO, C3H6, C3H8, H2 and reduction of NO, the steam-reforming reactions of C3H6, C3H8, the water-gas shift reaction of CO have been considered. Moreover, an oxygen-storage sub-model has been introduced, to account for the behavior of Cerium oxides. A detailed thermal model of the converter takes into account the heat released by the exothermic reactions as a source term in the heat transfer equations. The influence of the insulating mat is accounted.

This document describes the 2-D computer-aided design (CAD) template for the HPM-1 H-point machine or HPD available from SAE. The elements of the HPD include the curve shapes, datum points and lines, and calibration references. The intended purpose for this information is to provide a master CAD reference for design and benchmarking. The content and format of the data files that are available are also described.

This document describes the 2-D computer-aided design (CAD) template for the HPM-1 H-point machine or HPD available from SAE. The elements of the HPD include the curve shapes, datum points and lines, and calibration references. The intended purpose for this information is to provide a master CAD reference for design and benchmarking. The content and format of the data files that are available are also described.

A theoretical model is presented for predicting springback of wide sheet metal subjected to 2D-stretch-bending operation. The material is assumed to be normal anisotropic with n-th power hardening law, σ = Fεn. Two types of stretch-bending experiment, bending with simultaneous stretching and stretch-bending followed by consecutive re-stretching, is conducted using AK sheet steel and sheet aluminum alloy A5182-O. The measured values of springback are in good agreement with analytical ones for a wide range of bending radii, stretching forces, and loading conditions. Furthermore, a calculation method for predicting springback configurations of 2D sheet metal parts with arbitrary cross-sections which include both stretch-bending and stretch-bending-unbending deformation is proposed.

THE development of the two-stage torque converter with automatic double clutch is presented here. The author covers particularly the substitution of casting for fabrication for several of the units in the transmission.

Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumption and NOx emissions. Currently, CAI combustion is constrained at part load operation conditions because of misfire at low load and knocking combustion at high load, and the lack of effective means to control the combustion process. Extending its operating range including high load boundary towards full load and low load boundary towards idle in order to allow the CAI engine to meet the demand of whole vehicle driving cycles, has become one of the key issues facing the industrialisation of CAI/HCCI technology. Furthermore, this combustion mode should be compatible with different fuels, and can switch back to conventional spark ignition operation when necessary. In this paper, the CAI operation is demonstrated on a 2-stroke gasoline direct injection (GDI) engine equipped with a poppet valve train.

This paper describes the engineering, manufacturing and integration necessary to produce the Corvette's first ever all-aluminum spaceframe (see Figure 1). The engineering and manufacturing of the spaceframe was a joint venture between General Motors and suppliers ALCOA (Aluminum Company of America) and Dana Corporation. ALCOA led the initial design of the spaceframe; Dana Corp led the manufacturing; General Motors' Engineering and Manufacturing groups led the integration of the assembly. The aluminum spaceframe design is modeled after the baseline steel structure of the Corvette coupe. The aluminum spaceframe reduces 140 lbs from the steel baseline and enters the plant at 285 lbs. This frame allows the 2006 Corvette Z06 to enter the market at a 3100 lbs curb weight. Aluminum casting, extruding, stamping, hydroforming, laser welding, Metal Inert Gas (MIG) welding, Self Pierce Riveting (SPR), and full spaceframe machining make up the main technologies used to produce this spaceframe.

The General Motors (GM) Corvette design team was challenged with providing a C6 Z06 vehicle spaceframe that maintained the structural performance of its C5 predecessor while reducing mass by at least 56 kg. An additional requirement inherent to the project was that the design must be integrated into the C6 assembly processes with minimal disruption, i.e. seamless integration. In response to this challenge, a collaborative team was formed, consisting of design engineers from General Motors, Alcoa and Dana Corporation. The result of this collaborative effort is an aluminum Z06 spaceframe that satisfies the high performance expectations of the vehicle while reducing the mass by approximately 62 kg. The frame consists of aluminum extrusions, castings and sheets joined by MIG welding, laser welding and self-piercing rivets. The extrusions are 6XXX series alloys, the castings are permanent mold A356 while the sheet panels are formed from the 5XXX series of alloys.