News Release

Researchers explore hydrodynamic drag reduction

Book Announcement

World Scientific

Hydrodynamic Friction Drag Reduction

image: Presented in the figure is percent drag reduction, %DR, as a function of the span-wise gas flux, q, required to obtain Air Layer Drag Reduction (ALDR) on a 13m flat plate in the US Navy's Large Cavitation Channel with a free-stream speed of 11.1 m s-1. The threshold for ALDR was set at 80 percent drag reduction: the dark line in the figure. The different curves represent various downstream measurement positions relative to the injection location. As is evident in the figure, once sufficient air is injected, an air layer is formed with near total friction drag reduction for the length of the plate. view more 

Credit: Marc Perlin (University of Michigan, USA), Steven Ceccio (University of Michigan, USA)

Professors Perlin and Ceccio discuss the latest methods to effect hydrodynamic friction drag reduction and address the question as to which is the best technique to use for the various vehicles/projectiles one is trying to propel. These two researchers have worked in this field for about 15 years and have myriad papers and experience in this area.

The book, Mitigation of Hydrodynamic Resistance: Methods to Reduce Hydrodynamic Drag, covers in detail several methods of active and passive friction drag mitigation techniques including the timely and evolving topics of super-hydrophobic surfaces and the use of lifting bodies. In addition the authors discuss the use of gas injection to form air layers and cavities (now demonstrated successfully on full-scale ships) and polymer injection (costly, but efficient especially for one-time uses for example on weaponry) and appendages such as stern flaps and wedges.

Particular emphasis in the text is given to Air Layer Drag Reduction (ALDR), which has been shown to be effective both physically and economically in the laboratory and most recently in ocean-going vessels. The authors along with their co-workers have conducted extensive laboratory investigations of this technique, and were instrumental in advancing its state of the art.

This book will be invaluable to practicing professionals and individuals with advanced backgrounds in fluid mechanics who decide to master the available techniques of friction drag reduction. It will provide them with a working knowledge and the data with which to make decisions as to the most appropriate methods for drag reduction for a given application. The text can be used for a beginning graduate-level course, or for advanced undergraduate students in engineering and the physical sciences.

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More information on the book can be found at http://www.worldscientific.com/worldscibooks/10.1142/9198.

The book retails for US$85 / £56


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