Dieter Bothe – författare

This book presents experimental and numerical methods that have been developed during six years of targeted research within the DFG priority program SPP 1740, elucidating the interaction between hydrodynamics, mass transfer and transport as well as chemical reactions in bubbly flows.

This book presents experimental and numerical methods that have been developed during six years of targeted research within the DFG priority program SPP 1740, elucidating the interaction between hydrodynamics, mass transfer and transport as well as chemical reactions in bubbly flows.

This open access book explains the wetting of surfaces by fluids or their dewetting plays an important role in numerous processes in production engineering, energy technology and process engineering. However, the mutual influences between the dynamic wetting and dewetting processes and the local transport processes in terms of momentum, energy or material are not sufficiently understood and predictable, especially when the fluids and surfaces are complex and the processes are transient. The Collaborative Research Center 1194 of the German Research Foundation (CRC 1194) has derived 5 overarching goals for its research program: (1) In-depth understanding of the relationships and mechanisms of action of local momentum, heat and mass transport processes on wetting properties and vice versa; (2) Development of physically based, mathematical models, numerical methods and freely available simulation programs; (3) Development of high-resolution measurement methods for the experimental analysis of the interactions of transport and wetting processes, including the establishment of new measuring instruments; (4) Demonstration of the possibilities of targeted influencing and optimization of wetting processes by transport processes and vice versa; (5) Exemplary research into new and improved processes for selected, technically relevant applications. To achieve these goals, researchers from different disciplines (engineering, mathematics, natural sciences) work together in the CRC using complementary methods. This allows the processes to be investigated experimentally, theoretically and numerically on different length scales (nano-micro-meso-macro). In addition, a bridge is built between basic research and application-oriented research. The CRC comprises three project areas: (A) Generic Experiments (B) Modeling and Numerical Simulation and (C) New and Improved Applications. Two generic guiding configurations and OpenFOAM as a common software platform were established as important integrative brackets and for the common focus. The guiding configurations immersion body and droplet are, on the one hand, independent generic experiments that address complementary scientific questions and, on the other hand, arrangements that are taken up in numerous other experiments and that serve to validate the simulation models. In the last funding period, the focus lied on consolidating the comprehensive understanding and description of various coupled phenomena while further increasing the complexity of the fluids and surfaces.  In addition, the transfer of measurement technology was accelerated.

There are several physico-chemical processes that determine the behavior of multiphase fluid systems – e.g., the fluid dynamics in the different phases and the dynamics of the interface(s), mass transport between the fluids, adsorption effects at the interface, and transport of surfactants on the interface – and result in heterogeneous interface properties. In general, these processes are strongly coupled and local properties of the interface play a crucial role. A thorough understanding of the behavior of such complex flow problems must be based on physically sound mathematical models, which especially account for the local processes at the interface.This book presents recent findings on the rigorous derivation and mathematical analysis of such models and on the development of numerical methods for direct numerical simulations. Validation results are based on specifically designed experiments using high-resolution experimental techniques. A special feature of this book is its focus on an interdisciplinary research approach combining Applied Analysis, Numerical Mathematics, Interface Physics and Chemistry, as well as relevant research areas in the Engineering Sciences. The contributions originated from the joint interdisciplinary research projects in the DFG Priority Programme SPP 1506 “Transport Processes at Fluidic Interfaces.”