Flow control : fundamentals and practices
The potential benefits of realizing efficient flow-control systems range from saving billions of dollars in fuel costs for land, air and sea vehicles to achieving economically/environmentally more competitive industrial processes involving fluid flows. The understanding of some basic mechanisms in f...
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| Hlavní autori: | , , |
|---|---|
| Médium: | E-kniha Kniha |
| Jazyk: | English |
| Vydavateľské údaje: |
Berlin, Heidelberg
Springer
1998
Springer Berlin / Heidelberg Springer Berlin Heidelberg |
| Vydanie: | 1 |
| Edícia: | Lecture Notes in Physics Monographs |
| Predmet: | |
| ISBN: | 9783540639367, 3540639365, 9783662141922, 3662141922, 9783662141939, 3662141930 |
| ISSN: | 0940-7677 |
| On-line prístup: | Získať plný text |
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- 3.2 Wall Oscillation -- 3.3 Selective Interference -- 3.4 Selective Introduction Tecliniques -- 4 Concluding Remarks -- References -- 1 Introduction -- 2 System review -- 2.1 Background material on coupling mechanisms -- 2.2 Pulse combustion -- 2.3 Active combustion control -- 2.4 System identification -- 2.5 Active fluid mechanics and active combustion control -- 3 Control methods for combustion optimization -- 3.1 Actuators -- 3.2 Closed-loop control -- 3.3 Open-loop control -- 4 Flame response to external perturbations -- 4.1 Interactions between laminar flames and upstream flow modulations -- 4.2 Forcing of a turbulent ducted flame by longitudinal acoustic modes -- 4.3 Modulation of a turbulent spray flame -- 5 Application to pollutant emission -- 5.1 NO_x reduction: global effects -- 5.2 NO_x reduction: local effects -- 6 Conclusions -- References -- Chaos, Coherence and Control -- 1 Historical Setting -- 2 Control of Temporal Chaos -- 2.1 Using Chaotic Sensitivity -- 2.2 Implementations -- 2.3 Higher Dimensionality -- 3 Control of Spatial Chaos -- 3.1 Horseshoes in Mixing Flows -- 3.2 Implementations -- 3.3 Coherent Structure Creation in Standard Map -- 3.4 Coherent Structure Creation in Chaotic Fluid Flow -- 4 Prognostication -- References
- Intro -- Flow Control -- Preface -- Contributors -- Contents -- Introduction to Flow Control -- 1 What Is Flow Control -- 2 Five Eras of Flow Control -- 3 Governing Equations -- 3.1 Equations of Motion at the Wall -- 3.2 The Kármán Integral Equation -- 3.3 Turbulent Flows -- 4 Unifying Principles -- 4.1 Control Goals and Their Interrelation -- 4.2 Classification Schemes -- 4.3 Free-Shear and Wall-Bounded Flows -- 4.4 Regimes of Reynolds and Mach Numbers -- 4.5 Convective and Absolute Instabilities -- 5 Transition Delay -- 5.1 Stability Modifiers -- 5.2 Wave Cancellation -- 5.3 Compliant Coatings -- 6 Separation Control -- 6.1 Steady Separation -- 6.2 Unsteady Separation -- 6.3 Velocity Profile Modifiers -- 6.4 Moving Walls -- 6.5 Time-Dependent Separation -- 6.6 Three-Dimensional Separation -- 6.7 Turbulators -- 6.8 Momentum Addition to Near-Wall Flow -- 6.9 Separation Provocation -- 7 Drag Reduction -- 7.1 Introductory Remarks -- 7.2 Turbulent Flows -- 7.3 Relaminarization -- 7.4 Synergism -- 8 Turbulence Augmentation -- 9 Noise Control -- 10 Concluding Remarks -- References -- Frontiers of Flow Control -- 1 Introduction -- 1.1 The Taming of the Shrew -- 1.2 Control of Turbulence -- 1.3 Outline -- 2 Suction -- 3 Coherent Structures -- 4 Reactive Control -- 4.1 Introductory Remarks -- 4.2 Targeted Control -- 4.3 Reactive Feedback Control -- 4.4 Required Characteristics -- 5 Chaos Control -- 5.1 Nonlinear Dynamical Systems Theory -- 5.2 Chaos Control -- 6 Microfabrication -- 7 Soft Computing -- 7.1 Neural Networks -- 8 Concluding Remarks -- References -- Some Notes on Drag Reduction in the Near-Wall Region -- 1 The Structure of the Bursting Process -- 1.1 Length and Velocity Scales -- 1.2 The Principal Eddies in the Bursting Process -- 1.3 Inner-Outer Relationship in the Shear Flow -- 2 Analogies with Transitional Flows
- 3 Aspects of Control of Bounded Turbulent Flows -- 3.1 Global versus Selective Control -- 3.2 Selective Suction -- 3.3 Spanwise Wall Disturbances -- 3.4 Actuators in the Wall Region -- 3.5 Control Algorithms -- 4 Conclusions -- References -- Large-Scale-Structure Identification and Control in Turbulent Shear Flows -- 1 Introduction -- 1.1 Tools and Methods -- 1.2 Active Control -- 2 Large-Scale Structure Identification Scheme -- 2.1 Overview -- 2.2 Accessing the Large-Scale Structure -- 2.3 Excited vs Natural Approaches -- 2.4 Detection Methods -- 3 The Particular Case of POD -- 3.1 The POD Approach in Brief -- 3.2 Formal Definition of POD -- 3.3 The POD Theorem -- 3.4 Different POD Approaches -- 3.5 POD and Harmonic Analysis -- 3.6 Evaluative Summary of the POD Approach -- 3.7 Some Typical Applications of POD -- 3.8 Some Typical Results: Application to the Plane Mixing Layer. -- 3.9 LSE and Complementary Technique. -- 4 Flow Control by POD based Dynamical Systems -- 4.1 Deterministic Approach of Turbulence -- 4.2 Development of POD Based Dynamical System -- 4.4 Vorticity Transport Equation -- 4.5 The Plane Mixing Layer -- 4.6 Representativity of the Dynamical System Model -- 5 Concluding Remarks -- References -- Books/Workshops -- Multiscale Active Flow Control -- 1 Physics and its Modeling -- 1.1 Physics of Multiscale Flows -- 1.2 Modeling of Unsteady Flows -- 1.3 Theoretical Problems Related to Control -- 2 Turbulence Enhancement Using Active and Passive Control -- 2.1 Enhancement of Perturbation Process -- 2.2 Strategies of Control -- 2.3 Cost Function and Heat and Mass Transfer Enhancement -- 2.4 Basic Flow Characteristics and their Use in Control -- 2.5 Critical Point Design and Control -- 2.6 Noise Generation and Receptivity Control -- 2.7 Experimental Work in Progress -- 3 Turbulence Suppression by Passive and Active Control
- 3.1 Strategies of Control -- 3.2 Applicability of the Strategies -- 3.3 Control of Flows with Internal Mode Coupling -- 3.4 Direct Control of Separation -- 4 Problems in Practical Design of Flow Control Systems -- 4.1 Introduction to Engineering Problems -- 4.2 Problems of Methodology -- 4.3 Basic Problems for Design -- 4.4 Design for Qualification, Certification -- 5 Parting Remark -- References -- Control of Free Turbulent Shear Flows -- 1 Basics and Principles -- 1.1 Introduction -- 1.2 Description-Typology and Characterization of Free Shear Flows -- 1.3 Control Versus Management -- 1.4 Some History -- 1.5 What Do We Want to Achieve? - Aims of Control -- 1.6 What Mean Do We Command? - Methods and Mechanisms -- 1.7 Effects of Compressibility -- 1.8 Goals and Gains - The Question of Efficiency or is it Worth the Effort? -- 1.9 Summary and Charts -- 2 Jets & -- Wakes -- 2.1 Introduction - Definitions, Configurations, Concepts -- 2.2 Jets -- 2.3 Wakes -- 2.4 Juxtaposition and Summary -- 3 Mixing Layers -- 3.1 Introduction, Configurations, Definitions -- 3.2 Purpose of Control - Goals -- 3.3 Stability and Structures -- 3.4 Control via Boundary Conditions -- 3.5 Control via Flow Field / Field Effects -- 3.6 Three-Dimensional Configurations and Special Effects -- 4 Mixed Cases -- 4.1 Introduction -- 4.2 Separating/Separated Flows (Mixing Layer with Wall Effects) -- 4.3 Confined Flow -- 4.4 Combined Flows -- 4.5 Summarizing Remarks -- 5 General Surnmary -- References -- Near-Wall Turbulence Control -- 1 Introduction -- 2 Riblets -- 2.1 Methods for Simulating Flow Over Riblets -- 2.2 Spectral-Element-Fourier Methods -- 2.3 Finite Volume Methods -- 2.4 Viscous Wall Region Modelling -- 2.5 Results from Near-Wall Viscous Model and Direct Numerical Simulations -- 3 Alternative and Complementary Techniques -- 3.1 Three Dimensional Riblets or Humplets
- to Flow Control -- Frontiers of Flow Control -- Some Notes on Drag Reduction in the Near-Wall Region -- Large-Scale-Structure Identification and Control in Turbulent Shear Flows -- Multiscale Active Flow Control -- Control of Free Turbulent Shear Flows -- Near-Wall Turbulence Control -- Combustion Enhancement by Active Control -- Chaos, Coherence and Control.