Accession Number : AD0719232

Title :   Secondary Flows in Jets and Their Effects on Fluidic Components,

Corporate Author : HARRY DIAMOND LABS WASHINGTON D C

Personal Author(s) : Trask,R. Pierce , II ; Drzewiecki,Tadeusz M.

Report Date : OCT 1970

Pagination or Media Count : 48

Abstract : On the basis of physical and mathematical arguments it is shown that the flow of a fluid from a nozzle of rectangular cross section contains an axial component of vorticity, called secondary flow, that is directly related to the Reynolds number and inversely related to the radius of curvature of the nozzle. The results of tests on open channels, water tunnels, and air models are given, verifying the presence of these secondary flows. As a consequence of the propagation of this vorticity downstream with the jet, the attachment of a three-dimensional jet is found to be considerably different from the often assumed two-dimensional case. Known secondary flows were introduced through the power nozzle into two typical fluidic units, and the operating characteristics were found to change considerably but predictably, based on the knowledge of the sense of rotation and cellular structure of the imposed secondary flow. (Author)

Descriptors :   (*FLUIDICS, *SECONDARY FLOW), (*JETS, SECONDARY FLOW), NOZZLES, REYNOLDS NUMBER, VORTICES, THREE DIMENSIONAL FLOW, TWO DIMENSIONAL FLOW

Subject Categories : Fluidics and Fluerics

Distribution Statement : APPROVED FOR PUBLIC RELEASE