Turbulent flow over a wavy wall in a horizontal channel is investigated by experimental and numerical methods. The thorough problem understanding can advance turbulent flow physics knowledge for separating and reattaching flows. Another important consideration is the performance evaluation of mathematical models used in computational fluid dynamics (CFD) codes to predict the flow characteristics. This study explores numerical models because they are critically important to the design and performance evaluation of engineering systems. The experimental data are obtained to provide repository data and more insights into the flow physics considering both the flow development and fully periodic regions. A channel with a wavy bottom wall is considered for this study, and its main characteristic is a value of 10 for the ratio between the wave length and wave amplitude. A high-resolution particle image velocimetry (PIV) system is used to obtain detailed measurements of velocity at Reynolds number of 5040, 8400, 10700 and 13040 in both the developing and fully periodic regions. The numerical simulations are performed with a commercial CFD code using four eddy viscosity turbulence models and three Second-Moment Closure (SMC) turbulence models. This work assessed the predictive accuracy of a total of seven turbulence models. The experimental study covered a lack of data for the flow development within the waves, prior the periodic condition region, and it supported the turbulence models evaluation. The experiments provided features of the flow such as the recirculation regions, Reynolds stresses, and turbulent kinetic energy production at different channel locations. A comprehensive comparison between models and experimental data revealed a significant dependency on the turbulence model formulation and on the wall treatment selection for the flow development and fully periodic regions predictions.

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This book allows readers to tackle the challenges of turbulent flow problems with confidence. It covers the fundamentals of turbulence, various modeling approaches, and experimental studies. The fundamentals section includes isotropic turbulence and anistropic turbulence, turbulent flow dynamics, free shear layers, turbulent boundary layers and plumes. The modeling section focuses on topics such as eddy viscosity models, standard K-E Models, Direct Numerical Stimulation, Large Eddy Simulation, and their applications. The measurement of turbulent fluctuations experiments in isothermal and stratified turbulent flows are explored in the experimental methods section. Special topics include modeling of near wall turbulent flows, compressible turbulent flows, and more.

A guide to the essential information needed to model and compute turbulent flows and interpret experiments and numerical simulations Turbulent Fluid Flow offers an authoritative resource to the theories and models encountered in the field of turbulent flow. In this book, the author – a noted expert on the subject – creates a complete picture of the essential information needed for engineers and scientists to carry out turbulent flow studies. This important guide puts the focus on the essential aspects of the subject – including modeling, simulation and the interpretation of experimental data - that fit into the basic needs of engineers that work with turbulent flows in technological design and innovation. Turbulent Fluid Flow offers the basic information that underpins the most recent models and techniques that are currently used to solve turbulent flow challenges. The book provides careful explanations, many supporting figures and detailed mathematical calculations that enable the reader to derive a clear understanding of turbulent fluid flow. This vital resource: Offers a clear explanation to the models and techniques currently used to solve turbulent flow problems Provides an up-to-date account of recent experimental and numerical studies probing the physics of canonical turbulent flows Gives a self-contained treatment of the essential topics in the field of turbulence Puts the focus on the connection between the subject matter and the goals of fluids engineering Comes with a detailed syllabus and a solutions manual containing MATLAB codes, available on a password-protected companion website Written for fluids engineers, physicists, applied mathematicians and graduate students in mechanical, aerospace and civil engineering, Turbulent Fluid Flow contains an authoritative resource to the information needed to interpret experiments and carry out turbulent flow studies.