Injection Technologies and Mixture Formation Strategies For Spark-Ignition and Dual-Fuel Engines

Description

Fuel injection systems and performance is fundamental to combustion engine performance in terms of power, noise, efficiency, and exhaust emissions. There is a move toward electric vehicles (EVs) to reduce carbon emissions, but this is unlikely to be a rapid transition, in part due to EV batteries: their size, cost, longevity, and charging capabilities as well as the scarcity of materials to produce them. Until these issues are resolved, refining the spark-ignited engine is necessary to address both sustainability and demand for affordable and reliable mobility. Even under policies oriented to smart sustainable mobility, spark-ignited engines remain strategic, because they can be applied to hybridized EVs or can be fueled with gasoline blended with bioethanol or bio-butanol to drastically reduce particulate matter emissions of direct injection engines in addition to lower CO2 emissions. In this book, Alessandro Ferrari and Pietro Pizzo provide a full review of spark-ignited engine fuel injection systems. The most popular typologies of fuel injection systems are considered, with special focus on state-of-the-art solutions. Dedicated sections on the methods for air mass evaluation, fuel delivery low-pressure modules, and the specific subsystems for idle, cold start, and warm-up control are also included. The authors pay special attention to mixture formation strategies, as they are a fundamental theme for SI engines. An exhaustive overview of fuel injection technologies is provided, and mixture formation strategies for spark ignited combustion engines are considered. Fuel Injection Systems illustrates the performance of these systems and will also serve as a reference for engineers who are active in the aftermarket, offering detailed information on fuel injection system solutions that are mounted in older vehicles. Cover Table of Contents Preface 1 SI Engine Historical Background and Fuel Equipment Evolution 1.1 Historical Framework of SI Combustion Engines 1.2 Early History of Fuel Equipment for SI Engines 1.3 The Working Principle of Modern SI Engines 1.3.1 Two-Stroke Engines 1.4 Recent History of Fuel Equipment for SI Engines 1.5 Classification of Fuel Injection Systems for SI Engines 2 Injection System Tasks 3 Air Mass Evaluation 3.1 Speed-Density Method 3.2 Throttle-Valve Position Speed Method 3.3 Mechanical Flowmeters 3.4 Thermo-Electrical Flowmeters 4 Fuel-Delivery Modules for Gasoline Engines 4.1 Electronic Intermittent PFI Systems 4.1.1 Single-Point PFI Systems 4.1.2 Multipoint PFI Systems 4.1.3 Electrical Driving Commands of the Injector 4.1.4 Latest Generation Multipoint PFI Systems 4.2 Mechanical Intermittent PFI Systems 4.2.1 The Bosch Pump 4.2.2 The LUCAS Distributor 4.2.3 The SPICA Pump 4.2.4 The Kugelfischer Pump 4.3 Continuous PFI Systems 5 Idle, Cold-Start, and Warm-Up Control in PFI Systems 5.1 Air Subsystem 5.2 Fuel Subsystem Devices 6 Gasoline Direct Injection 6.1 Liquid GDI High-Pressure Systems 6.1.1 Systems with Constant Maximum Pressure 6.1.2 Systems With Variable Injection Pressure 6.1.2.1 First-Generation GDI Systems 6.1.2.2 Second-Generation GDI Systems 6.1.2.3 Injectors for GDI Applications 6.1.2.4 Injector Spray Patterns for GDI Systems 6.1.3 Ram-Tuned Systems 6.2 Air-Assisted GDI Systems 6.2.1 Electronic Air-Assisted GDI Systems for Four-Stroke Engines 6.2.2 Electronic Air-Assisted GDI Systems for Two-Stroke Engines 6.2.3 Mechanical Air-Assisted GDI Systems for Two-Stroke Engines 7 Gasoline Engine Performance and Emissions 7.1 Stratified Charge GDI Engines 7.1.1 Wall-Guided and Air-Guided Systems 7.1.2 Spray-Guided Combustion Systems 7.2 Homogeneous GDI Versus PFI Engines 7.3 In Cylinder Flows in GDI Engines 7.3.1 Bulk Flow Strategies for Stratified Charge Combustion Systems 7.3.2 Spray Momentum-Induced Turbulence 7.4 GDI Engine Operating Modes and the Corresponding Injection Strategies 7.5 Combustion Characteristics of GDI and PFI Engines 7.6 Comparison of the Fuel Consumption and Performance Between GDI and PFI Engines 7.7 Unburnt Hydrocarbons and Carbon Monoxide Emissions of GDI and PFI Engines 7.8 The Nitrogen Oxide Emissions of GDI and PFI Engines and the General Effects of EGR 7.9 The PM Emissions of GDI Engines 7.10 The Evolution of the GDI Concept Over the Last Two Decades 7.11 Ultrahigh Injection Pressure in Modern GDI Engines 7.11.1 Hydraulic Characteristics and Spray Configuration 7.11.2 Emissions and Fuel Consumption 7.12 Impact of Multiple Injections on GDI Engines 8 Innovative Architectures and Mixture Formation Strategies 8.1 Double-Injection Systems 8.1.1 Double-Injector PFI Systems 8.1.2 Combined GDI–PFI Systems 8.2 An Advanced Combustion System for Spark-Ignition Engines: Turbulent Jet Ignition 8.2.1 Passive Prechamber Systems 8.2.2 Active Prechamber Systems 8.3 Controlled Autoignition Engines 8.3.1 Homogenous Charge CI History 8.3.2 HCCI Concept 8.3.3 Challenges of CAI Combustion 8.3.4 Operating Range 8.3.5 Methods Used to Enlarge the Operating Range 8.4 Reactivity Controlled Compression Ignition (RCCI) Engines 8.4.1 Definition of the RCCI Concept and Employment of SI Engine Fuels in RCCI Engines 8.4.2 Mixture Formation, Its Reactivity, and Combustion in RCCI Engines 8.4.3 Engine-Out Emissions 8.4.4 Benefits and Weak Points of RCCI Combustion 9 Alternative Fuels for Modern Spark-Ignition and Dual-Fuel Engines 9.1 Liquefied Petroleum Gas Engines 9.1.1 Performance and Emissions of Vapor-Phase LPG PFI Engines 9.1.2 Liquid-Phase LPG Port Fuel and DI Engines 9.2 The NG Engine 9.2.1 Stoichiometric NG Engines With PFI Systems 9.2.2 Lean NG Engines 9.2.3 DI in NG Engines 9.2.4 Fuel Injection Systems for NG Engines 9.3 Hydrogen Internal Combustion Engines 9.3.1 Hydrogen Production and the Perspectives of Its Usage as a Fuel for Future Green Vehicles 9.3.2 Hydrogen Properties 9.3.3 Stoichiometric and Lean Hydrogen ICEs 9.3.4 Injection and Ignition Strategies for Hydrogen ICE 9.3.5 On-Board Vehicle Storage and Fuel Supply Systems for Hydrogen 9.4 Hints on the Use of Methanol in Engines 9.4.1 Methanol Production 9.4.2 Methanol as a Fuel for SI Engines 9.4.3 Methanol Usage in Dual-Fuel Engines References Index About the Authors