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This study investigates if particulates from a GDI engine can be significantly suppressed by use of ultra-high injection pressures under 2 different engine conditions known to be associated with high particulate numbers (PN): warm-up and transients. Experiments were carried out in a single-cylinder GDI engine equipped with an endoscope connected to a high-speed camera to enable combustion visualization. To mimic the warming-up, the coolant temperature was varied between 20 °C and 90 °C. A Diesel injector with modified nozzle was used and the injection pressures were varied between 400 and 1500 bar. The results revealed that increasing the fuel injection pressure decreased engine out HC and PN under warming-up conditions. However, the coolant water temperature was the most dominant factor affecting the emissions. For coolant temperature of 20 °C, the use of 1500 bar fuel injection pressure in comparison to lower fuel pressures resulted in significantly lower PN.

Continuous improvement of gasoline engine emissions performance is required to further protect the global environment and also the impact of emissions on a local level. During real world driving, transient engine operation and variation in fuel injection, airflow, and wall temperature are key factors to be controlled. Due to the limited opportunity for optimization of engine control, generation of a well-mixed fuel spray is necessary to create a suitable combustion environment to minimize emissions. Optimum spray performance achieves minimum surface wetting as well as promoting evaporation and diffusion if wetting occurs. Improvement in spray homogeneity is an important step to achieve this. Higher fuel pressure is initially considered to achieve improvements, as it is expected to improve mixture formation by reduction of wall wetting due to high atomization and lower penetration, as well as improvement in spray homogeneity.

According to the advance of engine control development, demands for direct sensing of physical quantity have been growing. Regarding pressure sensing, key properties for direct sensing are robustness against high temperature and pressure, and response time in addition to accuracy. In this work, a pressure sensor module with these key properties was developed. First of all, a piezoelectric device was selected as a suitable sensing principle for the required properties because of its thermally stable piezoelectric effect and potential for simple installation structure. Regarding robustness against temperature, the sensor module was designed to form thermal isolation layer with outer housing which is optimized according to its application. Regarding robustness against pressure and response time, breakage of the piezoelectric element is the main technical issue.

In respect to the present large refrigerator trucks, sub-engine type is the main product, but the basic structure does not change greatly since the introduction for around 50 years. A sub-engine type uses an industrial engine to drive the compressor, and the environmental correspondence such as the fuel consumption, the emission is late remarkably. In addition, most of trucks carry the truck equipment including the refrigerator which consumes fuel about 20% of whole vehicle. Focusing on this point, the following are the reports about the system development plan for fuel consumption reduction of the large size refrigerator truck. New concept is to utilize electrical power from HV system to power the electric-driven refrigerator. We have developed a fully electric-driven refrigerator system, which uses regenerated energy that is dedicated for our refrigerator system.

In general, CFD analysis with porous media is precise enough to simulate airflow behavior in a heat exchanger core, placed in the vehicle. In a case when the airflow behavior is complex, however, the precision lowers according to our study. Therefore, we developed a new modeling method to keep high-precision and applied it to analysis of airflow in the vehicle. The concept is at first that the shape of tubes and the distance between the tubes are as the actual product so that the airflow with an oblique angle is to pass through a core. With this concept, airflow with an oblique angle hits the surface of tubes and passes through a core with changing the direction. Next, the concept is to reproduce the air pressure loss in actually-shaped fins, and therefore, we use a porous medium for the modeling of the fins instead of the product shape modeling to combine with the the tubes.

Tightening global emissions standards are driving automotive Original Equipment Manufacturer’s (OEM’s) to utilize Three Way Catalyst (TWC) aftertreatment systems that can perform with greater efficiency and greater measured control of Precious Group Metals (PGM) use. At the same time, TWC aftertreatment systems minimize exhaust system pressure drops. This study will determine the influence of catalyst substrate cell geometry on emission and PGM usage. Additionally, a study of lightoff and backpressure comparisons will be conducted. The two substrate configurations used are hex/750cpsi and square/750cpsi.

We propose a verification method in the field of automotive control systems integrating the concepts of Formal Methods with testing, aiming at efficient and reliable software development. Although Formal Methods are believed to provide the benefits of their rigorous nature and their inherent capability of automation, only limited cases are known where Formal Methods were applied in system and software development, in practice, due to two major difficulties: appropriate abstraction in modeling and scalability in automated reasoning. Focusing on testing on the other hand, there is the difficulty of selecting reasonable set of tests for given verification objectives. In order to overcome these difficulties, our approach is to present verification criteria for testing to appropriately cover the property with the help of the Formal Method concepts.

This study reports on a new generation ECS (Ejector Cycle System) which includes a highly efficient ejector and a novel system configuration. The ejector is working as a fluid jet pump that recovers expansion energy which is wasted in the conventional refrigeration cycle decompression process, and converts the recovered expansion energy into pressure energy and raises the compressor suction pressure. Consequently, the ejector system can reduce power consumption of the compressor by using the above mentioned pressure-rising effect and improve energy efficiency of the refrigeration cycle. The ejector consists of a nozzle, a suction section, a mixing section and a diffuser. The objective of this study is to improve actual fuel economy of all vehicles by ejector technology. The previous generation ECS was reported in 2012 SAE World Congress1. Now, a new generation ECS has been successfully developed and released in the market for Mobile Air Conditioning systems as of 2013.

Emission regulations in many countries and regions around the world are becoming stricter in reaction to the increasing awareness of environment protections, and it has now become necessary to improve the performance of catalytic converters to achieve these goals. A catalytic converter is composed of a catalytically active material coated onto a ceramic honeycomb-structured substrate. Honeycomb substrates play the role of ensuring intimate contact between the exhaust gas and the catalyst within the substrate’s flow channels. In recent years, high-load test cycles have been introduced which require increased robustness to maintain low emissions during the wide range of load changes. Therefore, it is extremely important to increase the probability of contact between the exhaust gas and catalyst. To achieve this contact, several measures were considered such as increasing active sites or geometrical surface areas by utilizing substrates with higher cell densities or larger volumes.

Diesel common rail injectors are required to utilize a higher injection pressure and to achieve higher injection accuracy in order to meet increasingly severe emissions, less fuel consumption, and higher engine performance demand. In addition to those requirements, in conjunction with optimized nozzle geometry, a more rectangular injection rate and stable multiple injections with shorter intervals are required for further emissions and engine performance improvement by optimizing the combustion efficiency.

In automobiles, Integrated Starter Generators (ISGs) are important components since they ensure significant fuel economy improvements. With motors that operate at high voltage such as ISGs, it is important to accurately know partial discharge inception voltages (PDIVs) for the assured insulation reliability of the motors. However, the PDIVs vary due to various factors including the environment (temperature, atmospheric pressure and humidity), materials (water absorption and degradation) and voltage waveforms. Consequently, it is not easy either empirically or analytically to ascertain the PDIVs in a complex environment (involving, for example, high temperature, low atmospheric pressure and high humidity) in which many factors vary simultaneously, as with invehicle environments. As a well-known method, PDIVs can be analyzed in terms of two voltage values, which are the breakdown voltage of the air (called “Paschen curve”) and the shared voltage of the air layer.

The growing functionality and complexity of recent vehicle electronic systems have made inter-device communication (on-board LAN) technology vital to vehicle design. By field of application, the LAN (Local Area Network) systems currently in use are LIN (Local Interconnect Network) used for body systems, CAN (Controller Area Network) used for control systems, and MOST (Media Oriented Systems Transport ) used for multimedia and camera systems, and work to standardize the next-generation communication technology for each of those fields is underway. This paper provides a technical overview of the CXPI (Clock Extension Peripheral Interface) communication protocol, which satisfies the body system requirements (rapid response, system extensibility, high reliability, and low cost). It also presents the progress made on standardization at SAE and other organizations.

Recently, diesel engine manufacturers have been improving the tolerance of fuel injection quantity and timing in response to the strengthening of emissions regulations and the introduction of various kinds of diesel fuels. This paper describes the Intelligent Accuracy Refinement Technology (i-ART) system, which has been developed as a way of achieving substantially improved tolerances. The i-ART system consists of a fuel pressure sensor installed in the injectors. It calculates the injection quantity and timing at high speed using a dedicated microcomputer designed for pressure waveform analysis. As the injector can directly measure the fuel injection pressure waveform for each injection, it can compensate the injection quantity and timing tolerance at any time. Toyota Motor Corporation has introduced this system in Brazilian market vehicles. In Brazil, the PROCONVE L6 emissions regulations will be introduced in 2012, and the market also uses various kinds of diesel fuels.

A new development environment is required where conflict between control systems is minimized, where processing can be executed while maintaining independence between systems, and where quality can be assured easily. This environment must enable flexibility in software layouts to accommodate software changes during the development process and the parallel development of multiple derivative systems. We have developed virtualization technology (virtual CPU), which allows the execution of system control with a single CPU without conflict between systems. An outstanding virtual CPU architecture that we have developed allows us to execute multiple real-time control tasks with the hardware scheduler, and we have developed hardware that extends the management of address space and interrupt handling, making it possible for a single CPU to be configured as multiple CPUs. Also, we have implemented a bus system that reduces interference between threads.

Combustion-pressure-data-based feedback control of fuel injection and EGR is the most promising diesel system, since it can reduce fuel consumption and emissions, as well as noise and vibration, and improve the evaluation efficiency for adapting engine performance to. We developed a combustion pressure sensor installed inside the glow plug. This is superior in maintainability and ease of installation, and can detect the combustion pressure in each cylinder at high accuracy and low cost, with no need for engine modification.

A new exhaust emission control system has been developed which complies with the world's most severe emission standard: CARB PZEV. Leaner combustion in cold condition was enabled and rapid warm-up of a close-coupled catalyst was realized by utilizing a newly developed Intake Air Control Valve (IACV) system and hyper-atomization fuel injector. In addition, the newly developed HC adsorbing type 3-way catalyst realized cold HC reduction at lower cost. For further reduction of the exhaust emission, the Variable Valve Timing-Intelligent (VVT-i) system was positively operated immediately after the cold start. By the suitable operation of Variable Valve Timing (VVT), the blow-back from the cylinder enhanced the fuel atomization and re-burning of remaining unburned hydrocarbons (HCs), and increased in-cylinder residual gas reduces NOx.

In SI engines with port injection system, the injected fuel spray adheres surely on the port wall and the inlet valve, consequently, the spray-wall interaction process leads to the generation of unburned hydrocarbons and uncontrollable mixture formation. This paper deals with the fuel mixture preparation process including basic research on characteristics of the wall-wetted fuel film on a flat wall inside a constant volume vessel. In the experiments, iso-octane mixed with biacetyl as a tracer dopant was injected through a pintle type injector against a flat glass wall under the ambient conditions of atmospheric pressure and room temperature. The thickness of the adhered fuel film on the wall was quantitatively measured by using laser induced fluorescence (LIF) technique, which provides 2-D distribution information with high special resolution as a function of the injection duration, the impingement distance from the injector to the wall, and the impingement angle against the wall.

Fuel atomization is known as an effective means of reducing exhaust emissions from internal combustion engines. In this study, we present a cost-effective atomization method for multiple-hole nozzle gasoline injection systems that requires no auxiliary device or external energy source to carry out atomization. While many studies have been conducted before on the atomization mechanism, most assume that the key to atomization lies in the nozzle configuration or the interaction between the fuel spray and ambient air. We, on the other hand, paid particular attention to the fuel nozzle upstream flow and found how it plays a crucial role in fuel atomization. In case of using multiple-hole nozzle in particular, atomization is greatly influenced by impingement of upstream flow of the fuel nozzle, which leads to rapid directional change in the fuel flow.