Finally, the effects of kinetic and transport coupling on ignition and flame propagation are investigated by using dimethyl ether (DME) blended methane/air mixtures. It is shown that the addition of a small amount of DME to methane leads to a significant decrease in the ignition time, while the flame speed of DME/CH4/air mixture is only linearly proportional to the DME fraction.

Extensively using experimental and numerical illustrations, CombustionPhenomena: Selected Mechanisms of Flame Formation, Propagation, and Extinction provides a comprehensive survey of the fundamental processes of flame formation, propagation, and extinction. Taking you through the stages of combustion, leading experts visually display, mathematically explain, and clearly theorize on important physical topics of combustion. After a historical introduction to the field, they discuss combustion chemistry, flammability limits, and spark ignition. They also study counterflow twin-flame configuration, flame in a vortex core, the propagation characteristics of edge flames, instabilities, and tulip flames. In addition, the book describes flame extinction in narrow channels, global quenching of premixed flames by turbulence, counterflow premixed flame extinction limits, the interaction of flames with fluids in rotating vessels, and turbulent flames. The final chapter explores diffusion flames as well as combustion in spark- and compression-ignition engines. It also examines the transition from deflagration to detonation, along with the detonation wave structure. With downloadable resources of images that beautifully illustrate a range of combustion phenomena, this book facilitates a practical understanding of the processes occurring in the conception, spread, and extinguishment of a flame. It will help you on your way to finding solutions to real issues encountered in transportation, power generation, industrial processes, chemical engineering, and fire and explosion hazards.

This thesis presents pioneering experimental and numerical studies on three aspects of the combustion characteristics of lean premixed syngas/air flames, namely the laminar flame speed, extinction limit and flammability limit. It illustrates a new extinction exponent concept, which enriches the combustion theory. Above all, the book provides the following: a) a series of carefully measured data and theoretical analyses to reveal the intrinsic mechanisms of the fuel composition effect on the propagation and extinction of lean syngas/air flames; b) a mixing model and correlation to predict the laminar flame speed of multi-component syngas fuels, intended for engineering computations; c) a new “extinction exponent” concept to describe the critical effects of chemical kinetics on the extinction of lean premixed syngas/air flames; and d) the effects and mechanism of the dilution of incombustible components on lean premixed syngas/air flames and the preferential importance among the thermal, chemical and diffusion effects.

This book consists of papers on the recent progresses in the state of the art in natural computation, fuzzy systems and knowledge discovery. The book is useful for researchers, including professors, graduate students, as well as R & D staff in the industry, with a general interest in natural computation, fuzzy systems and knowledge discovery. The work printed in this book was presented at the 2020 16th International Conference on Natural Computation, Fuzzy Systems and Knowledge Discovery (ICNC-FSKD 2020), held in Xi'an, China, from 19 to 21 December 2020. All papers were rigorously peer-reviewed by experts in the areas.