Potential of Water Injection for Gasoline Engines by Means of a 3D-CFD Virtual Test Bench


Book Description

Water injection is one of the most promising technologies to improve the engine combustion efficiency, by mitigating knock occurrences and controlling exhaust gas temperature before turbine. As result, the engine can operate at stoichiometric conditions over the whole engine map, even during the more power-demanding RDE cycles. Antonino Vacca presents a methodology to study and optimize the effect of water injection for gasoline engines by investigating different engine layouts and injection strategies through the set-up of a 3D-CFD virtual test bench. He investigates indirect and direct water injection strategies to increase the engine knock limit and to reduce exhaust gas temperature for several operating points.




Investigation of Innovative Water Injection Strategies for Gasoline Engines by Means of a 3D-CFD Virtual Engine Test Bench


Book Description

This book focuses on the investigation of innovative engine technologies that can improve the efficiency of internal combustion engines and reduce their environmental impact. In particular, water injection is examined as a means of improving engine behavior. The possible combination of water injection with renewable fuels is also a topic of the book. The results of this experimental and numerical research show positive results that can be used for further research and development of engines. Content 3D-CFD Simulation Environment: the Virtual Engine Test Bench Experimental Spray Analysis and 3D-CFD Injection Model Calibration Applicability of Water Injection in Combination with an eFuel Water-in-Fuel Emulsions at the Virtual Engine Test Bench Target Groups Students and researchers in the field of automotive engineering, esp. engine technology Engineers in the automotive industry About the Author Edoardo Rossi is a project manager in the virtual engine development department at the FKFS, where he did his PhD. He works on innovative solutions for future powertrain technologies for motor vehicles. .




Knocking in Gasoline Engines


Book Description

The book includes the papers presented at the conference discussing approaches to prevent or reliably control knocking and other irregular combustion events. The majority of today’s highly efficient gasoline engines utilize downsizing. High mean pressures produce increased knocking, which frequently results in a reduction in the compression ratio at high specific powers. Beyond this, the phenomenon of pre-ignition has been linked to the rise in specific power in gasoline engines for many years. Charge-diluted concepts with high compression cause extreme knocking, potentially leading to catastrophic failure. The introduction of RDE legislation this year will further grow the requirements for combustion process development, as residual gas scavenging and enrichment to improve the knock limit will be legally restricted despite no relaxation of the need to reach the main center of heat release as early as possible. New solutions in thermodynamics and control engineering are urgently needed to further increase the efficiency of gasoline engines.










End-zone Water Injection as a Means of Suppressing Knock in a Spark-ignition Engine


Book Description

Summary: An investigation has been made of the effectiveness of water injection into the combustion end zone of a spark-ignition engine cylinder for the suppression of knock. Pressure-time recoreds obtained show that injection of water at 60° B.T.C. on the compression stroke at a water-fuel ratio of 0.3 rendered M-3 fuel as good as S-3 fuel from an antiknock consideration. The optimum crank angle for injection of water into the end zone was found to be critical. As the injection angle was increased beyond the optimum, the quantity of water required to suppress knock increased to 3.6 water-fuel ratio at 132° B.T.C. The water quantity could not be increased beyond 3.6 water-fuel ration because of injection-pump limitations; however, a further increase in the injection angle up to the earliest angle obtainable, which was 20° A.T.C. on the intake stroke, continuously increased the knock intensity. The engine operating conditions of the tests did not simulate those encountered in flight, especially with regard to the operating speed of 570 rpm. For this reason the results should only be regarded as of theoretical importance until further investigation has been made.




Reciprocating Engine Combustion Diagnostics


Book Description

This book deals with in-cylinder pressure measurement and its post-processing for combustion quality analysis of conventional and advanced reciprocating engines. It offers insight into knocking and combustion stability analysis techniques and algorithms in SI, CI, and LTC engines, and places special emphasis on the digital signal processing of in-cylinder pressure signal for online and offline applications. The text gives a detailed description on sensors for combustion measurement, data acquisition, and methods for estimation of performance and combustion parameters. The information provided in this book enhances readers’ basic knowledge of engine combustion diagnostics and serves as a comprehensive, ready reference for a broad audience including graduate students, course instructors, researchers, and practicing engineers in the automotive, oil and other industries concerned with internal combustion engines.




Assessment of Fuel Economy Technologies for Light-Duty Vehicles


Book Description

Various combinations of commercially available technologies could greatly reduce fuel consumption in passenger cars, sport-utility vehicles, minivans, and other light-duty vehicles without compromising vehicle performance or safety. Assessment of Technologies for Improving Light Duty Vehicle Fuel Economy estimates the potential fuel savings and costs to consumers of available technology combinations for three types of engines: spark-ignition gasoline, compression-ignition diesel, and hybrid. According to its estimates, adopting the full combination of improved technologies in medium and large cars and pickup trucks with spark-ignition engines could reduce fuel consumption by 29 percent at an additional cost of $2,200 to the consumer. Replacing spark-ignition engines with diesel engines and components would yield fuel savings of about 37 percent at an added cost of approximately $5,900 per vehicle, and replacing spark-ignition engines with hybrid engines and components would reduce fuel consumption by 43 percent at an increase of $6,000 per vehicle. The book focuses on fuel consumption-the amount of fuel consumed in a given driving distance-because energy savings are directly related to the amount of fuel used. In contrast, fuel economy measures how far a vehicle will travel with a gallon of fuel. Because fuel consumption data indicate money saved on fuel purchases and reductions in carbon dioxide emissions, the book finds that vehicle stickers should provide consumers with fuel consumption data in addition to fuel economy information.