Boundary Layer Flow Over Elastic Surfaces


Book Description

Coverage includes: Experimental findings around coherent vortical structures (CVS) in turbulent boundary layers and methods of controlling them Static and dynamic mechanical characteristics of elastic composite coatings, as well as new techniques and devices developed for their measurement Combined methods of flow control and drag reduction, including the effect of injection of polymer solutions, elastic coatings and generated longitudinal vortical structures on hydrodynamic resistance Intended as a reference for senior engineers and researchers concerned with the drag reduction and the dynamics of turbulent boundary layer flows, Boundary Layer Flow over Elastic Surfaces provides a unique source of information on compliant surface drag reduction and the experimental techniques around it that have shown measurable and repeatable improvements over recent years.




Boundary Layer Flow over Elastic Surfaces


Book Description

While other methods of drag reduction are well-known in marine R&D and ship design environments worldwide, compliant coating drag reduction remains less well-known and poorly understood. This important book presents cutting-edge techniques and findings from research sources not generally accessible by Western researchers and engineers, aiding the application and further development of this potentially important technology. Beginning with an introduction to drag reduction that places the authors’ work on elastic surfaces and combined techniques in context, the book moves on to provide a comprehensive study of drag reduction through elastic coating with both flow and material properties considered. Coverage includes: Experimental findings around coherent vortical structures (CVS) in turbulent boundary layers and methods of controlling them Static and dynamic mechanical characteristics of elastic composite coatings, as well as new techniques and devices developed for their measurement Combined methods of flow control and drag reduction, including the effect of injection of polymer solutions, elastic coatings and generated longitudinal vortical structures on hydrodynamic resistance Intended as a reference for senior engineers and researchers concerned with the drag reduction and the dynamics of turbulent boundary layer flows, Boundary Layer Flow over Elastic Surfaces provides a unique source of information on compliant surface drag reduction and the experimental techniques around it that have shown measurable and repeatable improvements over recent years. This compilation of research findings and new techniques developed for measurement will aid R&D engineers, naval architects and senior designers in their quest to achieve drag reductions that will deliver significant efficiency savings. Unique source of information on compliant surface drag reduction—an important area of technology with practical application to ships—from otherwise inaccessible research studies Updates the knowledge-base on boundary layer flow and surface friction reduction, critical topics in the global quest for increased ship efficiency and fuel economy Reveals new techniques and devices developed for measurement and provides a comprehensive study of drag reduction through elastic coating with both flow and material properties covered







Ship Motions and Drag Reduction


Book Description




Experimental Hydrodynamics of Fast-Floating Aquatic Animals


Book Description

Experimental Hydrodynamics of Fast-Floating Aquatic Animals presents the latest research on the physiological, morphological and evolutionary factors in aquatic animal locomotion. Beginning with an overview on how to conduct experiments on swimming aquatic animals, assessing hydrodynamic forces, resistance and geometric parameters of animal bodies, the book then details how aquatic animals, such as fast-moving dolphins, can achieve high speeds without over-expelling their energy resources. It provides insights into investigations on how animals, including dolphins, sharks and swordfish can maneuver through water at high speeds, offering a natural model for improving human and technological underwater locomotion. This book is essential for researchers and practicing biologists interested in the study of aquatic animal locomotive physiology and its application to human technology. Advanced undergraduate and graduate students will also find this a helpful academic resource for further understanding animal hydrodynamics. Analyzes the locomotive benefits of bodily structures in aquatic animals such as cetacean species, penguins, sharks and fast-swimming fish species, such as the swordfish Features the latest research and firsthand investigative studies of aquatic animal hydrodynamic factors, including skin elasticity, fin shape and movement, bioenergy, and more Provides a comparison of human to animal hydrodynamics, detailing how energy is spent differently due to evolutionary advances in the latter




Experimental Hydrodynamics for Flow Around Bodies


Book Description

Experimental Hydrodynamics for Flow around Bodies explains complex novel experimental methodologies to solve a wide range of important flow problems in industry and research. The book starts by examining the fundamental physical laws necessary for the optimization of techniques for hydro-aeromechanics, heat engineering, and other disciplines related to flow. The reader is then provided with detailed explanations of novel experimental methods, along with the results of physical research. These results are also necessary for the construction of theoretical models that provide improved descriptions for numerous problems in various scientific fields. Frequent discussions, examples of practical applications throughout the text, and foundational, theoretical materials help a range of readers engage and apply these methods to problems in fields including drag reduction, noiseless movement, optimal maneuvering, intense heat transfer, control of separated vortices, wind power, economical energy consumption, and more. Provides instructions on the set up of innovative experiments for drag reduction that will be of great interest to researchers in aerospace, marine and automotive engineering Describes, in detail, a variety of novel experiments to investigate boundary layer flow, together with experimental data that can be used with computational models Assists with bio-inspired hydrodynamic design by providing models of a waving fin mover and investigations of analogs of hydrobiont skin covers




Turbulent Boundary Layer Flow Over Superhydrophobic Surfaces


Book Description

The objective of this project was to determine whether drag caused by turbulence in boundary layer flow can be reduced through the use of modified surfaces. This study encompassed the testing of four different surfaces: 1) Teflon SLIP, 2) Aluminum SLIP, 3) Honeycomb Superhydrophobic and 4) Polydimethylsiloxane elastomer (PDMSe) Superhydrophobic. Each of these surfaces uses specific geometrical surface features to modify the original water-surface interface. Due to the influence of the Green Fleet Initiative and the Navy's goal to increase the fleet efficiency, the Office of Naval Research is interested in determining the effectiveness of these surfaces in boundary layer flow under operating conditions similar to those in which Navy ships operate. The goal of this study was to provide data and analysis detailing the effect of these surfaces on boundary layer turbulence and drag reduction. The performance of each surface was compared with that of a smooth wall under similar operating conditions to characterize the effectiveness of each modified surface.




Boundary Layer and Flow Control


Book Description

Boundary Layer and Flow Control: Its Principles and Application, Volume 2 focuses on the layer of fluid in the immediate area of a bounding surface where the effects of viscosity are substantial. This book is organized into two main topics—boundary layer control for low drag, and shock-induced separation and its prevention by design and boundary layer control. It specifically discusses the nature of transition, effect of two-dimensional and isolated roughness on laminar flow, and progress in the design of low drag aerofoils. The onset of separation effects for aerofoils and wings, shock-induced separation for laminar boundary layers, and shock-induced separation for laminar boundary layers are also deliberated. This volume is recommended to physicists and specialists interested in boundary layer and flow control.