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In a gasoline engine, the unswept in-cylinder residual gas and introduction of external EGR is one of the important means of controlling engine raw NOx emissions and improving part load fuel economy via reduction of pumping losses. Since the trapped in-cylinder Residual Gas Fraction (RGF, comprised of both internal, and external) significantly affects the combustion process, on-line diagnosis and monitoring of in-cylinder RGF is very important to the understanding of the in-cylinder dilution condition. This is critical during the combustion system development testing and calibration processes. However, on-line measurement of in-cylinder RGF is difficult and requires an expensive exhaust gas analyzer, making it impractical for every application. Other existing methods, based on measured intake and exhaust pressures (steady state or dynamic traces) to calculate gas mass flowrate across the cylinder ports, provide a fast and economical solution to this problem.

Accurate accounting for fresh charge (fuel and air) along with trapped RGF is essential for the subsequent thermodynamic analysis of combustion in gasoline engines as well as for on-line and real-time quantification as relevant to engine calibration and control. Cost and complexity of such techniques renders direct measurement of RGF impractical for running engines. In this paper, an empirically-based approach is proposed for on-line RGF, based on an existing semi-empirical model [1]. The model developed expands the range over which the semi-empirical model is valid and further improves its accuracy. The model was rigorously validated against a well correlated GT-POWER model as well as results from 1D gas exchange model [2]. Overall, using this model, RGF estimation error was within ∼1.5% for a wide range of engine operating conditions. The model will be implemented in Dyno development and calibration at Chrysler Group.

Devices for use in control of exhaust emissions have become indispensable to motorcycles. In order to evaluate quantitatively the effect of each device, the modal analysis system has to be required. The Modal Analysis System is one that classifies any driving schedule which is used for emissions measurement into four modes: idle, acceleration, cruise, and deceleration; then measures the emissions continuously using a mini-computer which accumulates the results of the analysis by mode. Instead of CO2 tracer method, we introduced the method of diluted exhaust gas measurement. In order for the system to produce reliable measurements, the accuracy of the total installation must be ensured. This paper describes the improvements of accuracy of analysers, technique on handling delay time and the verifications on the modal analysis system.

For a better understanding of the auto-ignition phenomenon in internal combustion engines, consideration is given from the in-cylinder gas temperature aspect. Experimental results demonstrate that the in-cylinder gas temperature at the end of compression, namely, the “auto-ignition temperature” is deeply involved in the onset of auto-ignition. The relation between the gas exchange state and the auto-ignition temperature explains the mechanism of timing controlled auto-ignition, namely, Activated Radical (AR) Combustion. The auto-ignition temperature is maintained constant during the AR combustion state, thanks to the exhaust valve controlling the hot residual gas amount. Finally, the utilization of auto-ignition in gasoline engines is discussed from the methodology aspect.

Gas shielded metal arc welding is generally applied to automobile chassis parts. However, the weld parts with the E-coat show poor corrosion resistance. Therefore, the corrosion mechanism of the weld parts was investigated. The results found two reasons why the weld parts corroded faster than the non weld parts:(1)inadequate phosphating (2)defects in the E-coat. After detailed investigation, it was clarified that the major cause of poor corrosion resistance was the defects in the E-coat caused by slags formed on the surface of the weld bead. Therefore the amount of slag has to be decreased to improve the corrosion resistance. The effect of shielding gas composition on the amount of slag was then investigated. In the case of Ar and oxidizing gas mixture, the corrosion resistance improved as the oxidizing gas content decreased. This was due to the reduction of slags.

Turbine housings in car engine turbochargers, which use costly stainless steel castings, account for nearly 50% of the parts cost of a turbocharger. They are also the component which controls the competitiveness of the turbocharger, in terms of both function and cost. In this research, focusing on thermal fatigue resistance which is one of the main functions demanded of a turbine housing, achieving reduction in wall thickness while securing sufficient thermal fatigue resistance, it is possible to reduce the amount of material used in the turbine housing and aimed for cost reduction. Therefore, we built a method to quantitatively predict, using 3D FEM, the lifespan from the initiation of thermal fatigue cracking to the formation of a penetrating crack which leads to gas leakage.

This paper addresses the critical parameters required for development of automotive thermal protection plans. The test conditions should consider the ambient air temperature, exhaust gas temperature, vehicle speed and engine speed. The choice of test conditions is critical in determining potential thermal issues during the development phase. Appropriate design alternatives can then be implemented.

In general, welding of high-pressure die casting (DC) parts has been difficult due to gases trapped in the castings. This is a result of the high-speed turbulent flow condition of the DC process. These gases are liberated during welding and produce porosity in the weld joint. The Author had found the range where an enough welding quality was obtained without great drop in castability to the middle of the laminar flow and turbulent flow. This range has been defined as the transition zone. Moreover high strength Al-Mg-Ni alloy was developed by non-heat-treatment. The Transition Flow Filling Method(TFFM) has been developed, that can not only reduce the amount of trapped gases but also is applicable to standard high pressure die casting equipment. With this method, high quality DC parts can be produced that are weldable, strong and have high toughness.

The reduction of NOx in exhaust gas has been a major challenge in diesel engine development. For the NOx reduction issues, a new Lean NOx Catalyst (LNC) aftertreatment system has been developed by Honda. A feature of the LNC system is the method that is used to reduce NOx through an NH₃-Selective Catalytic Reduction (NH₃-SCR). In an LNC system NOx is adsorbed at lean conditions, then converted to NH₃ at rich conditions and subsequently reduced in the next lean phase. In recent years, as the efficiency of the diesel engine has improved, the exhaust gas temperatures have been reduced gradually. Therefore, the aftertreatment system needs to be able to purify NOx at lower temperatures. The development of a new LNC which has a high activity at low temperature has been carried out. For the improvement of the LNC three material improvements were developed. The first of these was the development of a NOx adsorbent which is matching the targeted exhaust gas temperatures.

Using sand cores, the weld-able, hollow die-cast parts have been developed. For casting, the transition flow filling method is applied to reduce gas containment and to minimize damages to the core. In designing the products, the newly developed core stress prediction system by melt pressure distribution and the newly developed in-product gas containment prediction system have been applied. The hollow die-cast frame made by the new method attains a 30% increase in rigidity and 1kg reduction of weight.

In most motorcycle engines, blow-by gas is introduced into the air intake system, including the air cleaner, for the purpose of reducing the blow-by gas emissions in the crankcase. In such a system, the water and gasoline components of the blow-by gas get mixed into the engine oil under some driving conditions. This oil contamination shortens the oil replacement intervals. In order to reduce this problem, we devised a system to ventilate the crankcase positively and installed it on the engine of a small motorcycle. The system had a construction to draw fresh air with a one way valve that is actuated by the change in pressure inside the crankcase. The inside of the crankcase is ventilated by the fresh air. In the case of small motorcycle engines, if the gas positively ventilated from the inside of the crankcase were guided to the downstream of the throttle valve, the engine performance under low -loads, including idling, is significantly changed by the inflow of the gas.

Measuring the real-world performance of emission control technologies is an important aspect in the development of advanced low-emission vehicles. In addition, data acquired from such measurements can be used to improve the accuracy of air quality predictive models. Honda has developed an on-board sampling/analysis system capable of measuring on-road emissions at ULEV levels and below. Ambient air can be analyzed simultaneously. This FTIR-based system can measure several species; this paper will focus on NMHC, NOX, and CO. Techniques were developed to address the challenges associated with acquiring accurate real-time data at concentrations below 1 ppm in an on-road vehicle. Validation studies performed with reference gases and vehicle exhaust indicate a very good correlation between the on-road analyzer system and classic bench methods for all target compounds. Dynamic studies performed by the University of California, Riverside, also show good correlation.

A new nitriding technology and material technology have been developed to increase the strength of microalloyed gears. The developed nitriding technology makes it possible to freely select the phase composition of the nitride compound layer by controlling the treatment atmosphere. The treatment environment is controlled to exclude sources of supply of [C], and H2 is applied as the carrier gas. This has made it possible to control the forward reaction that decomposes NH3, helping to enable the stable precipitation of γ′-phase, which offers excellent peeling resistance. A material optimized for the new nitriding technology was also developed. The new material is a low-carbon alloy steel that makes it possible to minimize the difference in hardness between the compound layer and the substrate directly below it, and is resistant to decline in internal hardness due to aging precipitation in the temperature range used in the nitriding treatment.

1. On page 111, the authors have described a method to assess driver distraction. In this method, participants maintained a white square size on a forward display by using a game gas pedal of like in car-following situation. The size of the white square is determined by calculating the distance to a virtual lead vehicle. The formulas to correct are used to explain variation of acceleration of the virtual lead vehicle. The authors inadvertently incorporated old formulas they had used previously. In the experiments discussed in the article, the corrected formulas were used. Therefore, there is no change in the results. The following from the article:

A serpentine flow channel is one of the most common and practical channel layouts for a PEM fuel cell since it ensures the removal of water produced in a cell. While the reactant flows along the flow channel, it can also leak or cross to neighboring channels via the porous gas diffusion layer due to a high pressure gradient. Such a cross flow leads to effective water removal in a gas diffusion layer thus enlarging the active area for reaction although this cross flow has largely been ignored in previous studies. In this study, neutron radiography is applied to investigate the liquid water accumulation and its effect on the performance of a PEM fuel cell. Liquid water tends to accumulate in the gas diffusion layer adjacent to the flow channel area while the liquid water formed in the gas diffusion layer next to the channel land area seems to be effectively removed by the cross leakage flow between the adjacent flow channels.

A new type of lean NOx catalyst has been developed with improved thermal resistance. This lean NOx catalyst contains precious metals and NO2 adsorbents. The precious metals are used mainly for the oxidation reaction of NO, and the NO2 adsorbents are for the adsorption removal of generated NO2. The thermal resistance of the catalyst was raised by paying attention to the following points. 1) Improvement of thermal resistance for the NO oxidation activity by addition of a different precious metal element. 2) Prevention of thermal degradation of the NO2 adsorbent by addition of a new metal oxide. For item 1, Pd was added to the catalyst which had already included Pt. By having Pd coexist with Pt, the precious metal dispersion was kept high even after heat treatment, so the NO oxidizing ability was improved. For item 2, thermal degradation of NO2 adsorbent was prevented by addition of the new metal oxide (B) to the adsorbent.

Integration of the water and air treatment systems in confined habitats for extended duration space missions will require characterization of the constituents in the gases produced by biological water processors. A membrane bioreactor was constructed to accomplish nitrification as part of a denitrification-nitrification biological water processor to treat a simulated early planetary base wastewater. A gas chromatograph was installed inline to the influent and effluent gas lines of the membrane bioreactor to monitor nitrogen, oxygen, carbon dioxide and nitrous oxide. The inline monitoring system enabled sampling of gas effluent from the lumen of the membranes and from a gas-liquid separator. Mass flow of the gas streams was also measured to enable calculation of the mass flow rates of the four inorganic gases.

The variable intake and exhaust control valve system for the in-line four-cylinder motorcycle engine was developed for realization of high engine power in all the engine speed ranges. Both the variable intake and exhaust control valves are operated by one servomotor. For high engine speeds, the exhaust collector pipe design for merging of each exhaust gas flow at 180 degrees phase difference is used. For mid engine speeds, the design for merging of each exhaust gas flow at 360 degrees phase difference is used. Two modes are provided to the intake control, and three modes are provided to the exhaust control. Along with exhaust-gas treatment systems such as the catalyst and air-injection system, high engine performance with optimum driveability and reduced emission are realized.

Traditionally, vehicle emission testing has used non-intelligent analyzers to meet government-regulated standards. Typically, these instruments would provide a 0 to 5-volt signal to a central test cell computer which would then handle all calibrations including analyzer linearization, zero and span corrections, stability checks, time delays, and sample readings. Modern gas analyzers now contain intelligence within each individual analyzer; this has caused the calibration methods to change dramatically. New methods were developed in the bench control system to take advantage of the intelligence of the analyzers by creating a distributed control architecture. The zeroing, spanning, and linearization methods are quite different from the previous protocols. The results, however, will provide more accurate reading to be used in calculating vehicle emissions.

Catalyst simulation, which can analyze the complicated reaction pathway of exhaust gas purifications and identify the rate-determining step, is an essential tool in the development of catalyst materials. This requires an elementary reaction model which describes the detailed processes, i.e. adsorption, decomposition, and others. In our previous work, the elementary reaction model on Pt/CeO2 catalyst was constructed. In this study, we focused on extending the Zeolite catalyst and including the gas diffusivity through the catalyst layer. The reaction rate of a Zeolite catalyst was expressed by an Arrhenius equation, and the elementary reaction model was composed of 17 reactions. Each Arrhenius parameter was optimized by the catalytic activity measurements. The constructed model was validated with NOx conversion in cyclic experiments which were repeated with Lean phase (NOx adsorption) and Rich phase (NOx reduction).