Soliton/Like Coherent Structures in Fluid Mechanics

This open access book commemorates the 30th anniversary of the discovery of Solitons/like Coherent Structures (SCS) under experimental conditions, presenting a curated collection of contributions on SCS, the most important physical structures in the origin and development of turbulent flows. Different from previous books that focus on theory and numerical simulation, this book offers a comprehensive and systematic theoretical framework to address the global challenge of understanding the origins of turbulence from an experimental physics perspective. It begins with the common physical dynamics of turbulence within the boundary layer across various incoming flow conditions. Subsequently, it demonstrates that other significant shear flows have the same physical dynamical processes, uncovering the universal laws of the origin of turbulence. More importantly, it provided the key to solving the origin of turbulence- one of the two important aspects of the turbulence problem that has persisted for over a century. The research method provided in this book is unique: flow visualization is the first step of the experiment, followed by the quantitative measurement, and cross-validation. The experimental methods and experimental data processing methods are novel, developed surrounding the reconstruction of the three-dimensional flow structure. A distinguishing feature of this book is its integration of theory, experimentation, and computation, utilizing effective data processing and computational outcomes to construct a cohesive physical understanding. It starts with the simplest problem—small perturbation laminar boundary transitions—before exploring the complexities of turbulent boundary layer turbulence generation and ultimately extending this understanding to other flow types. This book is an invaluable resource for researchers and students in the field of turbulence physics.