Accession Number : ADD017336

Title :   Method And System For Reducing Drag On A Body Moving Through A Fluid Medium.

Descriptive Note : Patent, Filed 2 Sep 93, patented 15 Nov 94,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Katz, Richard A

Report Date : 15 Nov 1994

Pagination or Media Count : 18

Abstract : A method of detecting the onset of turbulence in connection with a body moving through a fluid medium and of reducing body drag and as well reducing the amount of drag noise radiated from the body. First, the body is supplied with sensors each for generating a signal suitable for measuring amplitude of pressures fluctuations of the of this medium proximate a region of said sidewall of the body in at least a region of the body in which turbulence is expected to occur. During a reference stage during which the body moves through the fluid medium when it is known that turbulence is occurring around at least a portion of said body, the sensors each generate reference temporal pressure data representing fluctuations in pressure of the fluid medium around said body. In response to reference temporal pressure data generated by sensors in a turbulence zone at which turbulence is occurring and sensors in a transition zone between the turbulence zone and a laminar flow zone, method-of-delay phase portraits are generated for a progression of selected delay intervals.

Descriptors :   *FLUID MECHANICS, *PATENTS, *DRAG REDUCTION, MEASUREMENT, DETECTORS, TURBULENCE, REGIONS, VARIATIONS, PRESSURE, DELAY, FLUIDS, TRANSITIONS, NOISE, DRAG, AMPLITUDE, LAMINAR FLOW, INTERVALS

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE