This book describes physical, mathematical and experimental methods to model flows in micro- and nanofluidic devices. It takes in consideration flows in channels with a characteristic size between several hundreds of micrometers to several nanometers. Methods based on solving kinetic equations, coupled kinetic-hydrodynamic description, and molecular dynamics method are used. Based on detailed measurements of pressure distributions along the straight and bent microchannels, the hydraulic resistance coefficients are refined. Flows of disperse fluids (including disperse nanofluids) are considered in detail. Results of hydrodynamic modeling of the simplest micromixers are reported. Mixing of fluids in a Y-type and T-type micromixers is considered. The authors present a systematic study of jet flows, jets structure and laminar-turbulent transition. The influence of sound on the microjet structure is considered. New phenomena associated with turbulization and relaminarization of the mixing layer of microjets are discussed. Based on the conducted experimental investigations, the authors propose a chart of microjet flow regimes. When addressing the modeling of microflows of nanofluids, the authors show where conventional hydrodynamic approaches can be applied and where more complicated models are needed, and they analyze the hydrodynamic stability of the nanofluid flows. The last part of the book is devoted the statistical theory of the transport processes in fluids under confined conditions. The authors present the constitutive relations and the formulas for transport coefficients. In conclusion the authors present a rigorous analysis of the viscosity and diffusion in nanochannels and in porous media.
The book introduces readers to the concept of weightlessness and microgravity, and presents several examples of microgravity research in fluid physics, the material sciences and human physiology. Further, it explains a range of basic physical concepts (inertia, reference frames, mass and weight, accelerations, gravitation and weightiness, free fall, trajectories, and platforms for microgravity research) in simple terms. The last section addresses the physiological effects of weightlessness. The book´s simple didactic approach makes it easy to read: equations are kept to a minimum, while examples and applications are presented in the appendices. Simple sketches and photos from actual space missions illustrate the main content. This book allows readers to understand the space environment that astronauts experience on board space stations, and to more closely follow on-going and future space missions in Earth orbit and to Mars.
The classic textbook on fluid mechanics is revised and updated by Dr. David Dowling to better illustrate this important subject for modern students. With topics and concepts presented in a clear and accessible way, Fluid Mechanics guides students from the fundamentals to the analysis and application of fluid mechanics, including compressible flow and such diverse applications as aerodynamics and geophysical fluid mechanics. Its broad and deep coverage is ideal for both a first or second course in fluid dynamics at the graduate or advanced undergraduate level, and is well-suited to the needs of modern scientists, engineers, mathematicians, and others seeking fluid mechanics knowledge. Over 100 new examples designed to illustrate the application of the various concepts and equations featured in the text A completely new chapter on computational fluid dynamics (CFD) authored by Prof. Gretar Tryggvason of the University of Notre Dame. This new CFD chapter includes sample MatlabTM codes and 20 exercises New material on elementary kinetic theory, non-Newtonian constitutive relationships, internal and external rough-wall turbulent flows, Reynolds-stress closure models, acoustic source terms, and unsteady one-dimensional gas dynamics Plus 110 new exercises and nearly 100 new figures
In a nutshell, it´s an eleven string, fretless, acoustic/electric instrument, strung with nylon strings and tuned to standard guitar tuning. More than ever before, musicians are mixing sounds and musical styles from all over the world. This often involves the mixing of Eastern and Western music, such as using a Sitar in a western musical setting or using western instruments to imitate the sounds in eastern music. The Glissentar was inspired by a similar desire to mix elements of East and West, but in this case, in the instrument itself. The Western part of the equation is easy to recognize as a variation on the guitar. All of the instruments basic dimensions, scale length, body size, depth, fingerboard radius, and string height, are fairly standard for acoustic/electric guitars. The Eastern influence in the Glissentar comes from the Oud, an ancestor of the Mandolin that dates back to the seventh century. The Oud is also an eleven-string fretless instrument and is still in use today primarily in Armenia and Egypt. Adapting to this new instrument is actually a great deal easier than it appears. The shape and scale of the neck and the easily visible side position markers help to give the Glissentar a very familiar feel. The Glissentar opens the door to microtonal playing as well as some incredible and unique new sounds for adventurous guitar players.SpecsRock Maple neckEbony Fingerboard16 fingerboard radius25 1/2 Scale1 3/4 nut widthTwo-Chamber Silver Leaf Maple bodySolid Cedar TopGodin Custom under-saddle Transducer & custom preampVolume, Mid, Treble and Bass controls
Diese Arbeit befasst sich mit der Lösung des direkten und inversen Streuproblems im Anwendungsbereich der zerstörungsfreien Prüfungen von Materialien mittels Ultraschallecho-Verfahren. Am Modell eines Spannbetonbauteils werden mit Hilfe numerischer Methoden ?Messdaten? erzeugt. Diese ?Messdaten? werden mit verschiedenen Inversionsalgorithmen unter Berücksichtigung von Materialinhomogenitäten analysiert und zur Abbildung von Materialfehlern verwendet. Dazu werden u.a. der ?konventionelle? Inversionsalgorithmus Synthetic Aperture Focusing Technique und die One-Way Wave-Equation-Methode vorgestellt. Die Algorithmen werden anhand des Impuls-Echo- und Linear-Array-Messverfahrens für akustische ?Messdaten? gegenübergestellt. Der Vergleich der Ergebnisse zeigt die Vor- und Nachteile beider Verfahren auf. Die Ergebnisse der SAFT- und Phasenauswertung für verschiedene Litzen- und Lufteinschlusskonstellationen veranschaulichen, wie schwierig ein Lufteinschluss in einem Spannbetonbauteil zu identifizieren ist.