Accession Number : AD0722390

Title :   Basic Studies in Flueric Demodulation,

Corporate Author : GENGE INDUSTRIES INC BURBANK CALIF FLUERIC DIV

Personal Author(s) : Unfried,H. H.

Report Date : OCT 1968

Pagination or Media Count : 61

Abstract : During an experimental study of flueric demodulation, it was noticed that a small degree of demodulation naturally occurs in the highly nonlinear flow associated with the growth of small disturbances in a laminar jet. It was discovered that a pronounced degree of demodulation could be obtained by including boundaries in the jet flow field. These forms of flueric demodulation are herein referred to as free shear flow and induced boundary layer demodulation respectively, and this report is concerned with the substantiation and explanation of these flow phenomena. The report also includes selected data describing the gain and bandwidth characteristics of an unbounded round laminar jet and data describing demodulation characteristics when a conical boundary is inserted on axis of a round jet. The entire study has been made with a one-half inch diameter water jet which is operated at a Reynolds number of 900, and is disturbed upstream of the nozzle by sinusoidal velocity perturbations at frequencies on the order of 3Hz. (It is believed that an air device operating in the KHz range could be designed using the Reynolds and Strouhal numbers as scaling parameters.) It has been observed that the disturbed shear flow augments the mean velocity of the bounding flow of the jet. It is presumed that the pseudo ring vortices induce a vortext boundary layer flow which has the observed effect of retarding the mean flow in the vicinity of the boundary. (Author)

Descriptors :   (*FLUIDICS, DEMODULATION), FLUID AMPLIFIERS, LIQUID JETS, VORTICES, BOUNDARY LAYER CONTROL, LAMINAR FLOW, JET MIXING FLOW

Subject Categories : Fluidics and Fluerics

Distribution Statement : APPROVED FOR PUBLIC RELEASE