Engine Fuel Interaction

Conventional fossil fuels will constitute the majority of automotive fuels for the foreseeable future but will have to adapt to changes in engine technology. Unconventional transport fuels such as biofuels, gas-to-liquid fuels, compressed natural gas, and liquid petroleum gas will also play a role. Hydrogen might be a viable transport fuel if it overcomes barriers in production, transport, storage, and safety and/or if fuel cells become viable. This book opens by considering these issues and then introduces practical transport fuels. A chapter on engine deposits follows, which is an important practical topic about how fuels affect engines that is not usually considered in other books. The next three chapters discuss auto-ignition phenomena in engines. The auto-ignition resistance of fuels is the most important fuel property since it limits the efficiency of spark ignition engines and determines the performance of compression ignition engines. Moreover, the manufacture of fuels is primarily driven by the need to meet auto-ignition quality demands set by fuel specifications. The final chapter considers the implications for future fuels. The book covers the many important ways that fuels and engines interact and why and how fuels will need to change to meet the requirements of future engines, as well as the implications for fuels manufacture and specifications.

This book focuses on droplets and sprays relevant to combustion and propulsion applications. The book includes fundamental studies on the heating, evaporation and combustion of individual droplets and basic mechanisms of spray formation. The contents also extend to the latest analytical, numerical and experimental techniques for investigating the behavior of sprays in devices like combustion engines and gas turbines. In addition, the book explores several emerging areas like interactions between sprays and flames and the dynamic characteristics of spray combustion systems on the fundamental side, as well as the development of novel fuel injectors for specific devices on the application side. Given its breadth of coverage, the book will benefit researchers and professionals alike.

In October 1975, while the United States was still acutely feeling the aftermath of the 1973 Arab Oil Embargo, the General Motors Research Laboratories held its nineteenth annual symposium. The proceedings of this timely symposium on "Future Automotive Fuels - Prospects, Performance, and Perspective" are reported in this book. We hope that it will serve not only as a permanent record of the papers and discussions, but also as a stimulus and inspiration for ideas, research, and development in the vital field of automotive fuels. The economy of the United States and the lifestyle of her people are woven together with energy into a unique fabric. Reducing the energy content of this fabric weakens it and can even destroy it. The Oil Embargo stunningly demonstrated how easy it is to attack this fabric, and exposed for all to see its greatest weaknes- reliance on imported petroleum. Since petroleum is the only current source of automotive fuels, and cars and trucks consume about 43 percent of the petroleum used in the United States, the Oil Embargo had its most profound and dramatic on automotive transportation: First there were long lines at service stations, impact and then idle lines in car assembly plants and long lines at unemployment offices. Against this grim setting, we planned the symposium on automotive fuels for the future.

Diesel engines power our world, but for a cleaner future, we need to look beyond the fuel spray itself. The hidden battleground lies in the interaction between the spray and the engine walls. Here, the fuel's fate is sealed - efficient combustion for power, or incomplete burning leading to harmful emissions. Ideally, the spray breaks up into tiny droplets that readily vaporize on contact with the walls. This creates a well-mixed air-fuel mixture for clean burning. However, forceful impacts can leave a fuel film, hindering vaporization and causing problems. The key to sustainable diesels lies in optimizing this wall interaction. Engineers are delving deeper, not just focusing on the spray itself, but also on injector design, injection pressure, and even the wall materials and temperatures. By controlling these factors, they can promote better mixing and minimize fuel wall impingement, leading to cleaner and more efficient combustion. This goes beyond just the spray - it's about understanding the delicate dance between fuel and walls, paving the way for a greener future for diesel engines.