The prediction of laminarization with a two-equation model of turbulence

A heat transfer textbook

Some Preliminary Thoughts * Part I: Inviscid Hypersonic Flow * Hypersonic Shock and Expansion-Wave Relations * Local Surface Inclination Methods * Hypersonic Inviscid Flowfields: Approximate Methods * Hypersonic Inviscid Flowfields: Exact Methods * Part II: Viscous Hypersonic Flow * Viscous Flow: Basic Aspects, Boundary Layer Results, and Aerodynamic Heating * Hypersonic Viscous Interactions * Computational Fluid Dynamic Solutions of Hypersonic Viscous Flows * Part III: High-Temperature Gas Dynamics * High-Temperature Gas Dynamics: Some Introductory Considerations * Some Aspects of the Thermodynamics of Chemically Reacting Gases (Classical Physical Chemistry) * Elements of Statistical Thermodynamics * Elements of Kinetic Theory * Chemical Vibrational Nonequilibrium * Inviscid High-Temperature Equilibrium Flows * Inviscid High-Temperature Nonequilibrium Flows * Kinetic Theory Revisited: Transport Properties in High-Temperature Gases * Viscous High-Temperature Flows * Introduction to Radiative Gas Dynamics.

Hypersonic and high temperature gas dynamics

Two new versions of the k-omega two-equation turbulence model will be presented. The new Baseline (BSL) model is designed to give results similar to those of the original k-omega model of Wilcox, but without its strong dependency on arbitrary freestream values. The BSL model is identical to the Wilcox model in the inner 50 percent of the boundary-layer but changes gradually to the high Reynolds number Jones-Launder k-epsilon model (in a k-omega formulation) towards the boundary-layer edge. The new model is also virtually identical to the Jones-Lauder model for free shear layers. The second version of the model is called Shear-Stress Transport (SST) model. It is based on the BSL model, but has the additional ability to account for the transport of the principal shear stress in adverse pressure gradient boundary-layers. The model is based on Bradshaw's assumption that the principal shear stress is proportional to the turbulent kinetic energy, which is introduced into the definition of the eddy-viscosity. Both models are tested for a large number of different flowfields. The results of the BSL model are similar to those of the original k-omega model, but without the undesirable freestream dependency. The predictions of the SST model are also independent of the freestream values and show excellent agreement with experimental data for adverse pressure gradient boundary-layer flows.

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Improved two-equation k-omega turbulence models for aerodynamic flows

Definition and properties of Lagrangian coherent structures from finite-time Lyapunov exponents in two-dimensional aperiodic flows

1 Introduction- 11 Momentum Transfer- 12 Heat and Mass Transfer- 13 Relations between Heat and Momentum Transfer- l4 Coupled and Uncoupled Flows- 15 Units and Dimensions- l6 Outline of the Book- Problems- References- 2 Conservation Equations for Mass, Momentum, and Energy- 21 Continuity Equation- 22 Momentum Equations- 23 Internal Energy and Enthalpy Equations- 24 Conservation Equations for Turbulent Flow- 25 Equations of Motion: Summary- Problems- References- 3 Boundary-Layer Equations- 3l Uncoupled Flows- 32 Estimates of Density Fluctuations in Coupled Turbulent Flows- 33 Equations for Coupled Turbulent Flows- 34 Integral Equations- 35 Boundary Conditions- 36 Thin-Shear-Layer Equations: Summary- Problems- References- 4 Uncoupled Laminar Boundary Layers- 41 Similarity Analysis- 42 Two-Dimensional Similar Flows- 43 Two-Dimensional Nonsimilar Flows- 44 Axisymmetric Flows- 45 Wall Jets and Film Cooling- Problems- References- 5 Uncoupled Laminar Duct Flows- 51 Fully Developed Duct Flow- 52 Thermal Entry Length for a Fully Developed Velocity Field- 53 Hydrodynamic and Thermal Entry Lengths- Problems- References- 6 Uncoupled Turbulent Boundary Layers- 61 Composite Nature of a Turbulent Boundary Layer- 62 The Inner Layer- 63 The Outer Layer- 64 The Whole Layer- 65 Two-Dimensional Boundary Layers with Zero Pressure Gradient- 66 Two-Dimensional Flows with Pressure Gradient- 67 Wall Jets and Film Cooling- Problems- References- 7 Uncoupled Turbulent Duct Flows- 71 Fully Developed Duct Flow- 72 Thermal Entry Length for a Fully Developed Velocity Field- 73 Hydrodynamic and Thermal Entry Lengths- Problems- References- 8 Free Shear Flows- 81 Two-Dimensional Laminar Jet- 82 Laminar Mixing Layer between Two Uniform Streams at Different Temperatures- 83 Two-Dimensional Turbulent Jet- 84 Turbulent Mixing Layer between Two Uniform Streams at Different Temperatures- 85 Coupled Flows- Problems- References- 9 Buoyant Flows- 91 Natural-Convection Boundary Layers- 92 Combined Natural- and Forced-Convection Boundary Layers- 93 Wall Jets and Film Heating or Cooling- 94 Natural and Forced Convection in Duct Flows- 95 Natural Convection in Free Shear Flows- Problems- References- 10 Coupled Laminar Boundary Layers- 101 Similar Flows- 102 Nonsimilar Flows- 103 Shock-Wave/Shear-Layer Interaction- 104 A Prescription for Computing Interactive Flows with Shocks- Problems- References- 11 Coupled Turbulent Boundary Layers- 111 Inner-Layer Similarity Analysis for Velocity and Temperature Profiles- 112 Transformations for Coupled Turbulent Flows- 113 Two-Dimensional Boundary Layers with Zero Pressure Gradient- 114 Two-Dimensional Flows with Pressure Gradient- 115 Shock-Wave/Boundary-Layer Interaction- References- 12 Coupled Duct Flows- 121 Laminar Flow in a Tube with Uniform Heat Flux- 122 Laminar, Transitional and Turbulent Flow in a Cooled Tube- References- 13 Finite-Difference Solution of Boundary-Layer Equations- 131 Review of Numerical Methods for Boundary-Layer Equations- 132 Solution of the Energy Equation for Internal Flows with Fully Developed Velocity Profile- 133 Fortran Program for Internal Laminar and Turbulent Flows with Fully Developed Velocity Profile- 134 Solution of Mass, Momentum, and Energy Equations for Boundary-Layer Flows- 135 Fortran Program for Coupled Boundary-Layer Flows- References- 14 Applications of a Computer Program to Heat-Transfer Problems- 141 Forced and Free Convection between Two Vertical Parallel Plates- 142 Wall Jet and Film Heating- 143 Turbulent Free Jet- 144 Mixing Layer between Two Uniform Streams at Different Temperatures- References- Appendix A Conversion Factors- Appendix B Physical Properties of Gases, Liquids, Liquid Metals, and Metals- Appendix C Gamma, Beta and Incomplete Beta Functions- Appendix D Fortran Program for Head's Method

Physical and Computational Aspects of Convective Heat Transfer

Analysis of turbulent boundary layers

Too many books on fluid mechanics are written on the strength of original material which makes up one chapter or less; the remainder being a restatement of the familiar contents of other books. This book by Cebeci and Bradshaw is totally free from such objections. The authors have both made very substantial contributions to knowledge in the area covered by the book. This shows clearly in the authority of the presentation, in the large number of very recent references and in the material, which is fresh and up-to-date without in any way being self-consciously trendy. Despite its title, the book is concerned with thin shear layers of all kinds and for the most part does not discuss them explicitly in terms of momentum transport: the title is presumably chosen to show that heat and mass transfer effects are not considered. The material covered is an impressive array of cases, representing the present state of knowledge. Far from the conventional concentration on two-dimensional wall boundary layers, the book gives considerable emphasis to both external and internal flows, to axisymmetric and three dimensional configurations and to free shear layers. Modern finite difference methods are described and, where appropriate, listings of Fortran programs are presented. The emphasis is on practical cases and practical methods of solution. A large number of novel and interesting problems and worked examples are given. The reviewer found the exposition uneven: in many parts, every comment carries an exciting new insight but in others the vision seems diminished and the presentation difficult to follow. A few passages consist of the presentation of the first author's research with little or no discussion of other methods. Surprisingly the derivation of the equations makes no mention of matched asymptotic expansions. Indeed, the laminar thin shear layer equations are accorded only the somewhat humble status of a data correlation. However, it would be unfair and misleading to emphasise minor shortcomings. The book is a powerful addition to the literature. It wil l demand an effort from its readers and is likely to be too advanced and uncompromising for undergraduate use but for postgraduate students and research workers, it is very welcome indeed. Any effort it demands is amply repaid. B. L. HUNT

Momentum transfer in boundary layers

Note: Exemplaire broche d'apres photocopie bibliotheque EPFZ (cote 731 891) Reference Record created on 2004-09-07, modified on 2016-08-08

Engineering Calculation Methods for Turbulent Flow

Description of a very simple and accurate numerical scheme which is applicable to quite general boundary-layer-flow problems. The scheme has been tested extensively on laminar flows, turbulent flows, wake flows etc. It is much faster, easier to program, and more flexible than most other numerical methods employed so far on such problems. It makes it also possible to compute extremely close to the point of separation with no special precautions. The inclusion of chemically reacting species offers no difficulties. The efficiency of the scheme clearly makes it applicable to three-dimensional steady, unsteady two-dimensional, and perhaps even unsteady three-dimensional, boundary-layer flows.

Tuncer Cebeci

Papers

Physical and Computational Aspects of Convective Heat Transfer

Analysis of turbulent boundary layers

Momentum transfer in boundary layers

Engineering Calculation Methods for Turbulent Flow

Accurate Numerical Methods for Boundary-Layer Flows. II: Two Dimensional Turbulent Flows