Written by experts in the field, this book, "Boundary Layer Flows - Theory, Applications, and Numerical Methods" provides readers with the opportunity to explore its theoretical and experimental studies and their importance to the nonlinear theory of boundary layer flows, the theory of heat and mass transfer, and the dynamics of fluid. With the theory's importance for a wide variety of applications, applied mathematicians, scientists, and engineers - especially those in fluid dynamics - along with engineers of aeronautics, will undoubtedly welcome this authoritative, up-to-date book.

A comprehensive review of techniques and methods for applying computational fluid dynamics (CFD) analysis to high speed inlets and related flows is provided via an extensive literature survey of such applications. Topics covered include governing equations, numerical integration schemes, boundary conditions, gridding requirements, and turbulence models. Results of applications from the literature survey shed light on the relative success of the techniques being used throughout the industry. (AN).

This report summarizes research conducted during the past year whose aim is to develop and test an accurate and efficient method for describing boundary-layer development in the transition region. A low-Reynolds-number version of the Wilcox k-w model has been postulated and tested against experimental data for 10 fully turbulent boundary layers and for more than 20 transitional cases. Overall discrepancies between theory and experiment are smaller than those for simpler correlations designed for use with algebraic turbulence models. Singular perturbation analysis of the compressible viscous sublayer and defect layer has been initiated with some interesting preliminary results. Some progress has been made toward eliminating the k-w model's sensitivity to the freestream boundary condition on w ... Transition, Turbulence modeling, Hypersonics, Computational fluid dynamics.

A new laminar-turbulent transition model for low-turbulence external aerodynamic applications is presented that incorporates linear stability theory in a manner compatible with modern computational fluid dynamics solvers. The model uses a new transport equation that describes the growth of the maximum Tollmien-Schlichting instability amplitude in the presence of a boundary layer. To avoid the need for integration paths and non-local operations, a locally defined non-dimensional pressure-gradient parameter is used that serves as an estimator of the integral boundary-layer properties. The model has been implemented into the OVERFLOW 2.2f solver and interacts with the Spalart-Allmaras and Menter SST eddy-viscosity turbulence models. Comparisons of predictions using the new transition model with high-quality wind-tunnel measurements of airfoil section characteristics validate the predictive qualities of the model. Predictions for three-dimensional aircraft and wing geometries show the correct qualitative behavior even though limited experimental data are available. These cases also demonstrate that the model is well-behaved about general aeronautical configurations. These cases confirm that the new transition model is an improvement over the current state of the art in computational fluid dynamics transition modeling by providing more accurate solutions at approximately half the added computational expense.

This second edition of the book, Modeling and Computation of Boundary-Layer Flows^ extends the topic to include compressible flows. This implies the inclusion of the energy equation and non-constant fluid properties in the continuity and momentum equations. The necessary additions are included in new chapters, leaving the first nine chapters to serve as an introduction to incompressible flows and, therefore, as a platform for the extension. This part of the book can be used for a one semester course as described below. Improvements to the incompressible flows portion of the book include the removal of listings of computer programs and their description, and their incor poration in two CD-ROMs. A listing of the topics incorporated in the CD-ROM is provided before the index. In Chapter 7 there is a more extended discussion of initial conditions for three-dimensional flows, application of the characteristic box to a model problem and discussion of flow separation in three-dimensional laminar flows. There are also changes to Chapter 8, which now includes new sections on Tollmien-Schlichting and cross-flow instabilities and on the predic tion of transition with parabolised stability equations, and Chapter 9 provides a description of the rational behind interactive boundary-layer procedures.

The aim of this book is to give, within a single volume, an introduction to the fields of turbulence modelling and transition-to-turbulence prediction, and to provide the physical background for today's modelling approaches in these problem areas as well as giving a flavour of advanced use of prediction methods. Turbulence modelling approaches, ranging from single-point models based on the eddy-viscosity concept and the Reynolds stress transport equations (Chapters 3,4,5), to large-eddy simulation (LES) techniques (Ch. 7), are covered. The foundations of hydrodynamical stability and transition are presented (Ch. 2) along with transition prediction methods based on single-point closures (Ch. 6), LES techniques (Ch. 7) and the parabolized stability equations (Ch. 8). The book addresses engineers and researchers, in industry or academia, who are entering into the fields of turbulence or transition modelling research or need to apply turbulence or transition prediction methods in their work.

Computational Fluid Dynamics (CFD) has been widely used in scientific research and engineering designs of aerospace vehicles. However, most Reynolds-averaged Navier-Stokes CFD applications today still assume fully turbulent flows, and so are unable to capture the boundary layer transition phenomenon. In the present study, the Local Correlation-based Transition Model (LCTM) was investigated and implemented in an unstructured CFD solver - U2NCLE, which is coupled with both one-equation Spalart-Allmaras (S-A) and two-equations Shear Stress Transport (SST) turbulence models. An innovative method was developed to evaluate the local free stream turbulence intensity for the transition model coupled with the S-A turbulence model. The current transition model was systematically validated on several benchmark cases including a flat plate with and without pressure gradients, two-dimensional airfoils, and realistic three-dimensional helicopter rotors. Both the S-A and SST based transition models were also used to predict the aerodynamic interactions in a lift fan configuration, to further explore the unsteady aerodynamic phenomena for internal viscous flows.

Second Enhanced Edition Suitable for advanced-level courses or an independent study in fluid mechanics, this text by an expert in the field provides the basic aspects of laminar-to-turbulent flow transition in boundary layers. Logically organized into three major parts, the book covers pre- and post-transitional flow, transitional flow, and several advanced topics in periodically disturbed transitional flow. Some of the subjects covered within the book include high-frequency unsteady laminar flow, turbulent flow, natural transition, bypass transition, turbulent spot theory, turbulent spot kinematics and production, correlations for the onset and rate of transition, global and conditional averaging, transitional flow models, wakeinduced transition, multimode transition, and separated-flow transition. Containing some 202 figures (all drawn by the author), 28 tables, 12 appendices, a supplement on tensors, and an extensive bibliography, the 415 page book provides a wealth of data and information about the subject.