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This book describes unified image-based measurement methods (theories, numerical methods, and algorithms) to determine the important physical quantities of complex flows in engineering and natural systems, including velocity, pressure, temperature, heat transfer, and skin friction. It presents a systematical study of the inverse problems in global flow diagnostics in a unified framework of the variational formulations. The authors further illustrate the main physical quantities in fluid mechanics, including velocity, pressure, skin friction and surface heat flux, extracted from flow visualization images obtained in experiments and observations. The developed methods are applicable in various image-based flow measurements in diverse disciplines ranging from fluid mechanics/aerodynamics to plenary sciences.

This book describes the importance of heat transfer in heat exchangers, and fluids properties play a vital role to increase heat transfer rate translating the size of the equipment and cuts in the capital and running cost in the long term. Nanofluids applications in heat exchangers will help to improve the thermophysical properties of the fluid and therefore heat transfer. And, this book explains the enhancing mechanisms of heat transfer by employing nanofluids in heat exchangers. A critical discussion will enable to estimate the pros and cons of such fluids in different types of heat exchangers. Prevailing working conditions for short- and long-term implementation of various types of nanofluids will be discussed and introduced to the readers. This book helps the researchers, scientist and academicians working in the domain to be able to get a comprehensive knowledge at one place regarding the preparation, properties, measurements, data reduction, characteristics and applications of nanofluids in heat exchangers.

This book focuses on the effects of the material, porosity, pore size and pore shape on flow behaviour and heat transfer in microscale porous media manufactured using a space holder method. It also describes a novel approach to studying flow behaviour in non-transparent materials such as porous metals via flow visualization in transparent media that mimic the porous structure. The book employs a combination of microparticle image velocimetry – a modern, advanced technique – and pressure drop measurement – a more traditional method – that makes the mechanistic study of several phenomena possible. It covers the identification of various flow regimes and their boundaries, velocity profiles on the microscale, the heat transfer coefficient under forced convection, and the correlation between flow behaviour on the pore scale and the convective heat transfer performance of the porous media. Understanding the fundamentals of porous flow, especially on the microscale, is critical for applications of porous media in heat exchangers, catalytic convertors, chemical reactors, filtration and oil extraction. Accordingly, this book offers a valuable resource for all researchers, graduate students and engineers working in the areas of porous flow and porous materials.

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.

Nanofluids are gaining the attention of scientists and researchers around the world. This new category of heat transfer medium improves the thermal conductivity of fluid by suspending small solid particles within it and offers the possibility of increased heat transfer in a variety of applications. Bringing together expert contributions from

The book is dedicated to the method and application potential of micro segmented flow. The recent state of development of this powerful technique is presented in 12 chapters by leading researchers from different countries. In the first section, the principles of generation and manipulation of micro-fluidic segments are explained. In the second section, the micro continuous-flow synthesis of different types of nanomaterials is shown as a typical example for the use of advantages of the technique in chemistry. In the third part, the particular importance of the technique in biotechnical applications is presented demonstrating the progress for miniaturized cell-free processes, for molecular biology and DNA-based diagnostics and sequencing as well as for the development of antibiotics and the evaluation of toxic effects in medicine and environment.

This work represents one of the first comprehensive attempts to seamlessly integrate two highly active interdisciplinary domains in soft matter science – microfluidics and liquid crystals (LCs). Motivated by the lack of fundamental experiments, Dr. Sengupta initiated systematic investigation of LC flows at micro scales, gaining new insights that are also suggestive of novel applications. By tailoring the surface anchoring of the LC molecules and the channel dimensions, different topological constraints were controllably introduced within the microfluidic devices. These topological constraints were further manipulated using a flow field, paving the way for Topological Microfluidics. Harnessing topology on a microfluidic platform, as described in this thesis, opens up capabilities beyond the conventional viscous-dominated microfluidics, promising potential applications in targeted delivery and sorting systems, self-assembled motifs, and novel metamaterial fabrications.

Diffuse interface (D.I.) model for muliphase flows.- Phase separation of viscous ternary liquid mixtures.- Dewetting and decomposing films of simple and complex liquids.- Phase-field models.Multiphase flows are typically described assuming that the different phases are separated by a sharp interface, with appropriate boundary conditions. This approach breaks down whenever the lengthscale of the phenomenon that is being studied is comparable with the real interface thickness, as it happens, for example, in the coalescence and breakup of bubbles and drops, the wetting and dewetting of solid surfaces and, in general, im micro-devices. The diffuse interface model resolves these problems by assuming that all quantities can vary continuously, so that interfaces have a non-zero thickness, i.e. they are'diffuse'. The contributions in this book review the theory and describe some relevant applications of the diffuse interface model for one-component, two-phase fluids and for liquid binary mixtures, to model multiphase flows in confined geometries.

This volume presents applications of the Pi-Theorem to fluid mechanics and heat and mass transfer. The Pi-theorem yields a physical motivation behind many flow processes and therefore it constitutes a valuable tool for the intelligent planning of experiments in fluids. After a short introduction to the underlying differential equations and their treatments, the author presents many novel approaches how to use the Pi-theorem to understand fluid mechanical issues. The book is a great value to the fluid mechanics community, as it cuts across many subdisciplines of experimental fluid mechanics.

Microfluidics and Microfabrication discusses the interconnect between microfluidics, microfabrication and the life sciences. Specifically, this includes fundamental aspects of fluid mechanics in micro-scale and nano-scale confinements and microfabrication. Material is also presented discussing micro-textured engineered surfaces, high-performance AFM probe-based, micro-grooving processes, fabrication with metals and polymers in bio-micromanipulation and microfluidic applications. Editor Suman Chakraborty brings together leading minds in both fields who also: Cover the fundamentals of microfluidics in a manner accessible to multi-disciplinary researchers, with a balance of mathematical details and physical principles Discuss the explicit interconnection between microfluiodics and microfabrication from an application perspective Detail the amalgamation of microfluidics with logic circuits and applications in micro-electronics Microfluidics and Microfabrication is an ideal book for researchers, engineers and senior-level graduate students interested in learning more about the two fields.

The subject of the book is uid dynamics and heat transfer in micro-channels. This problem is important for understanding the complex phenomena associated with single- and two-phase ows in heated micro-channels. The challenge posed by high heat uxes in electronic chips makes thermal management a key factor in the development of these systems. Cooling of mic- electronic components by new cooling technologies, as well as improvement of the existing ones, is becoming a necessity as the power dissipation levels of integrated circuits increases and their sizes decrease. Miniature heat sinks with liquid ows in silicon wafers could signi cantly improve the performance and reliability of se- conductor devices. The improvements are made by increasing the effective thermal conductivity, by reducing the temperature gradient across the wafer, by reducing the maximum wafer temperature, and also by reducing the number and intensity of localized hot spots. A possible way to enhance heat transfer in systems with high power density is to change the phase in the micro-channels embedded in the device. This has motivated a number of theoretical and experimental investigations covering various aspects of heat transfer in micro-channel heat sinks with phase change. The ow and heat transfer in heated micro-channels are accompanied by a n- ber of thermohydrodynamic processes, such as liquid heating and vaporization, bo- ing, formation of two-phase mixtures with a very complicated inner structure, etc., which affect signi cantly the hydrodynamic and thermal characteristics of the co- ing systems.

Microfluidics for Biological Applications provides researchers and scientists in the biotechnology, pharmaceutical, and life science industries with an introduction to the basics of microfluidics and also discusses how to link these technologies to various biological applications at the industrial and academic level. Readers will gain insight into a wide variety of biological applications for microfluidics. The material presented here is divided into four parts, Part I gives perspective on the history and development of microfluidic technologies, Part II presents overviews on how microfluidic systems have been used to study and manipulate specific classes of components, Part III focuses on specific biological applications of microfluidics: biodefense, diagnostics, high throughput screening, and tissue engineering and finally Part IV concludes with a discussion of emerging trends in the microfluidics field and the current challenges to the growth and continuing success of the field.