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In a competitive engineering business world, there is a constant demand to meet stringent emissions and on board diagnostic (OBD) regulations in a cost-effective manner. Engineers are tasked with the responsibility to innovate and design solutions around cost-cutting measures that involve reducing bill of material costs on the printed circuit board (PCB). Varied features in commercial application specific integrated circuits (ASIC) devices makes it more challenging to create consistent engineering design methods to provide critical inputs for controls and diagnostic strategies. In addition, continuous evolution of the emissions and OBD regulations in the different markets make it challenging for ASIC design manufacturers to evolve their hardware designs quickly. One such input is soak time. Soak time is typically defined as the amount of time the engine has been turned off. Emission controls and OBD algorithms use soak time to enable cold and hot start processing strategies.

Motorcycle usage continues to expand globally. Motorcycles use various fuels in different countries and regions, and it is required that they comply with emissions and fuel consumption regulations as specified in UN-GTR No.2 (WMTC). In general, a motorcycle engine has a large bore diameter and a high compression ratio due to demands of high performance. Poor fuel quality may cause damage to the engine, mainly by knocking. Knock control systems utilizing high-frequency vibration detection strategies like knock sensors, which are equipped on several sport-touring motorcycles, are not used widely for reasons of complex construction and high cost. This research aims to develop a new concept of combustion control for common motorcycle as an alternative.

In racing world regardless of two-wheeled vehicle (motorcycle) or four-wheeled vehicle, vehicle setting is performed in accordance with various race conditions. From the age of carburetor till even now ECU is used, vehicle setting executes as well and plays an important role. Changeover to electronic control makes vehicle control more precise; meanwhile, vehicle control technique to become complicated is occurring every day. Therefore, whenever a new competition vehicle is developed, tool required for vehicle setting is also necessary to be updated according to vehicle control technique implemented. Setting-method till now is that, all information required for vehicle setting is packaged in tool, thereby tool and vehicle have always been a combination of 1-to-1. Consequently, in manufacturer's vehicle development, tool development / update becomes a burden and leads to increment of development costs.

The Drive By Wire (hereafter referred to as DBW) system is the electronically throttle control system. It controls a throttle valve in order to aim at a suitable throttle position according to an engine operating condition and a demand of driver or rider. This system is basically composed of a throttle body with driving motor, an Accelerator Position Sensor (hereafter referred to as APS), and an Electronic Control Unit (hereafter referred to as ECU). The DBW system is spreading to motorcycle field as replacement of existing mechanical intake control system. This is because there are some advantages as the following especially in the large displacement model: capability for installation of several functions, flexibility in adaptation to recent environmental regulations, and effect on reduction of system cost, etc. In general, the motorcycle has some unique features compared with the automobile. Among them, important features for the DBW system are following three points.

The performance of Gasoline Direct Injection (GDI) engines is governed by multiple physical processes such as the internal nozzle flow and the mixing of the liquid stream with the gaseous ambient environment. A detailed knowledge of these processes even for complex injectors is very important for improving the design and performance of combustion engines all the way to pollutant formation and emissions. However, many processes are still not completely understood, which is partly caused by their restricted experimental accessibility. Thus, high-fidelity simulations can be helpful to obtain further understanding of GDI injectors. In this work, advanced simulation and experimental methods are combined in order to study the spray characteristics of two different 3-hole GDI injectors.

Opposed-piston engines have been in production since before the 1930’s because of their inherent low heat losses and high thermal efficiency. Now, opposed-piston gasoline compression ignition (OP-GCI) engines are being developed for automotive transportation with stringent emissions targets. Due to the opposed-piston architecture and the absence of a cylinder head, fuel injection requirements and packaging are significantly different than conventional 4-stroke engines with central-mounted injectors. The injection process and spray characteristics are fundamental to achieving a successful combustion system with high efficiency, low emissions, and low combustion noise. In this paper, the fuel injection system for the Achates 2.7L, 3-cylinder OP-GCI engine is described. The fuel system was designed for 1800 bar maximum fuel pressure with two injectors mounted diametrically opposed in each cylinder.

Fuel spray injected by a port injector has significant effects on engine power output and combustion efficiency. For this reason, it is necessary to atomize fuel into fine droplets and accurately supply it without being susceptible to any changes in temperature or negative pressure affected by engine. This document introduces an atomization technique with optimized layout of nozzle holes and drastically reduced pressure loss (energy loss) in the flow under a needle valve seat. It also describes an injector having a short fuel flow path and a small dead volume under the valve seat, which can have good resistance against any changes in temperature and negative pressure.

Continued improvement in the combustion process of internal combustion engines is necessary to reduce fuel consumption, CO2 emissions, and criteria emissions for automotive transportation around the world. In this paper, test results for the Gen3X Gasoline Direct Injection Compression Ignition (GDCI) engine are presented. The engine is a 2.2L, four-cylinder, double overhead cam engine with compression ratio ~17. It features a “wetless” combustion system with a high-pressure direct injection fuel system. At low load, exhaust rebreathing and increased intake air temperature were used to promote autoignition and elevate exhaust temperatures to maintain high catalyst conversion efficiency. For medium-to-high loads, a new GDCI-diffusion combustion strategy was combined with advanced single-stage turbocharging to produce excellent low-end torque and power. Time-to-torque (TT) simulations indicated 90% load response in less than 1.5 seconds without a supercharger.

We have extended application of fuel injectors (hereafter as “injector”) for small motorcycle engines in developing countries by making it compatible with various engine displacements and trims as well as satisfying the needs from a variety of operating and environmental conditions. The motorcycles with a small-displacement engine are mainly for developing countries and often have an uncovered engine. Accordingly, a noise-insulating cover was indispensable to insulate injector noises. Since it was necessary to attain a low cost for the complete motorcycle by eliminationof the noise-insulation cover for extensive application of an electronic fuel injection system (hereafter “FI”) in developing countries, we developed the quiet injector by thorough reduction of mass of the needle valve and lowering of the operation speed.

With the inception of model-based design and automatic code generation, many organizations are developing controls and diagnostics algorithms in model-based development tools to meet customer and regulatory requirements. Advances in model-based design have made it easier to generate C code from models and help software engineers streamline their workflow. Typically, after the software has been developed, the models are handed over to a calibration team responsible for calibrating the features to meet specified customer and regulatory requirements. However, once the models are handed over to the calibration team, the calibration engineers are unaware of how to calibrate the features because documentation is not available. Typically, model documentation trails behind the software process because it is created manually, most of this time is spent on formatting. As a result, lack of model documentation or up-to date documentation causes a lot of pain for OEM’s and Tier 1 suppliers.

A third generation Gasoline Direct Injection Compression Ignition (GDCI) engine has been designed and built. The engine is intended to meet stringent US Tier 3 emissions standards with diesel-like fuel efficiency. While nearly every aspect of the engine design has been improved over the previous second generation engine, this paper is primarily concerned with two of the most critical subsystems - the thermal management and EGR systems. These are especially important because gasoline compression ignition combustion is sensitive to intake gas temperature and exhaust gas dilution. Both parameters may deviate from steady state targets during transients. The quality of combustion control during transient vehicle operation is limited by significant response delay in both the thermal management and EGR systems. The intake air coolers must be sized for sufficient heat transfer capacity under peak load operating conditions, which results in coolers having significant thermal inertia.

Fuel stratification effects on the combustion and emissions behaviors for partially premixed compression ignition (PPCI) combustion of a high reactivity gasoline (research octane number of 80) was investigated using the third generation Gasoline Direct-Injection Compression Ignition (Gen3 GDCI) multi-cylinder engine. The PPCI combustion mode was achieved through a double injection strategy. The extent of in-cylinder fuel stratification was tailored by varying the start of second fuel injection timing (SOIsecond) while the first fuel injection event was held constant and occurred during the intake stroke. Based on the experimental results, three combustion characteristic zones were identified in terms of the SOIsecond - CA50 (crank angle at 50% cumulative heat release) relationship: (I) no response zone (HCCI-like combustion); (II) negative CA50 slope zone: (early PPCI mode); and (III) positive CA50 slope zone (late PPCI mode).