Turbulent Drag Reduction by Surfactant Additives

Turbulent Drag Reduction by Surfactant Additives
Author: Feng-Chen Li
Publisher: John Wiley & Sons
Total Pages: 233
Release: 2012-01-10
Genre: Science
ISBN: 1118181115

Turbulent drag reduction by additives has long been a hot research topic. This phenomenon is inherently associated with multifold expertise. Solutions of drag-reducing additives are usually viscoelastic fluids having complicated rheological properties. Exploring the characteristics of drag-reduced turbulent flows calls for uniquely designed experimental and numerical simulation techniques and elaborate theoretical considerations. Pertinently understanding the turbulent drag reduction mechanism necessities mastering the fundamentals of turbulence and establishing a proper relationship between turbulence and the rheological properties induced by additives. Promoting the applications of the drag reduction phenomenon requires the knowledge from different fields such as chemical engineering, mechanical engineering, municipal engineering, and so on. This book gives a thorough elucidation of the turbulence characteristics and rheological behaviors, theories, special techniques and application issues for drag-reducing flows by surfactant additives based on the state-of-the-art of scientific research results through the latest experimental studies, numerical simulations and theoretical analyses. Covers turbulent drag reduction, heat transfer reduction, complex rheology and the real-world applications of drag reduction Introduces advanced testing techniques, such as PIV, LDA, and their applications in current experiments, illustrated with multiple diagrams and equations Real-world examples of the topic’s increasingly important industrial applications enable readers to implement cost- and energy-saving measures Explains the tools before presenting the research results, to give readers coverage of the subject from both theoretical and experimental viewpoints Consolidates interdisciplinary information on turbulent drag reduction by additives Turbulent Drag Reduction by Surfactant Additives is geared for researchers, graduate students, and engineers in the fields of Fluid Mechanics, Mechanical Engineering, Turbulence, Chemical Engineering, Municipal Engineering. Researchers and practitioners involved in the fields of Flow Control, Chemistry, Computational Fluid Dynamics, Experimental Fluid Dynamics, and Rheology will also find this book to be a much-needed reference on the topic.

Turbulence Control by Passive Means

Turbulence Control by Passive Means
Author: E. Coustols
Publisher: Springer Science & Business Media
Total Pages: 183
Release: 2012-12-06
Genre: Technology & Engineering
ISBN: 9400921594

Proceedings of the 4th European Drag Reduction Meeting

Reactive Control of Turbulent Wall-Bounded Flows for Skin Friction Drag Reduction

Reactive Control of Turbulent Wall-Bounded Flows for Skin Friction Drag Reduction
Author: Stroh, Alexander
Publisher: KIT Scientific Publishing
Total Pages: 214
Release: 2019-01-04
Genre: Friction
ISBN: 3731507668

The work presents an attempt to improve the understanding of reactive drag reducing control of near-wall turbulence with respect to limitations present in a realistic application scenario. The reference reactive control scheme of opposition control is studied using direct numerical simulation through the consideration of various application oriented restrictions, i.e. local control application, limited spatial and temporal resolution of the scheme, sensor noise and control elements arrangement.

Turbulent Drag Reduction Using Compliant Coatings

Turbulent Drag Reduction Using Compliant Coatings
Author:
Publisher:
Total Pages: 0
Release: 2002
Genre:
ISBN:

An experimental study was carried in a water tunnel, where the drag of several compliant coatings in the turbulent boundary layer was measured. An axi-symmetric test model similar to that used by NUWC was designed and built, and identical compliant coatings were tested as a part of collaboration between UK, U.S. and Russia. While experimental results in the UK show small drag reductions by up to 3% in some of the compliant coatings tested, skin-friction drags of compliant coatings measured at MIT are consistently greater than that of rigid surface. The Russian data are not yet available at the time of writing this report. The aging of the compliant coatings are thought to be the reason for these discrepancies. A better coordination will be required for the rest of the program to overcome this problem.

Viscous Drag Reduction

Viscous Drag Reduction
Author: C. Sinclair Wells
Publisher: Springer
Total Pages: 497
Release: 2013-12-20
Genre: Technology & Engineering
ISBN: 1489955798

Turbulent Drag Reduction Using Micro and Nanotextured Ultrahydrophobic Surfaces

Turbulent Drag Reduction Using Micro and Nanotextured Ultrahydrophobic Surfaces
Author:
Publisher:
Total Pages: 17
Release: 2010
Genre:
ISBN:

This final report documents the findings of our research project which demonstrated through a combination of experimental measurements and numerical simulations that ultrahydrophobic surfaces can be used to delay the transition to turbulence and dramatically reduce drag in both external and internal turbulent flows. These enhancements should have a profound effect on a huge variety of existing technologies, resulting in benefits ranging from a reduction in the pressure drop in pipe flows to an increase in speed and efficiency in surface ships and small submersible vehicles.