Accession Number : ADA255454


Title :   Fully Nonlinear Goertler Vortices in Constricted Channel Flows and Their Effect on the Onset of Separation


Descriptive Note : Contractor rept.


Corporate Author : INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA


Personal Author(s) : Denier, James P ; Hall, Philip


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255454.pdf


Report Date : Jul 1992


Pagination or Media Count : 34


Abstract : The development of fully nonlinear Gortler vortices in the high Reynolds number flow in a symmetrically constricted channel is investigated. Attention is restricted to the case of 'strongly' constricted channels considered by Smith and Daniels (1981) for which the scaled constriction height is asymptotically large. Such flows are known to develop a Goldstein singularity and subsequently become separated at some downstream station past the point of maximum channel constriction. It is shown that these flows can support fully nonlinear Gortler vortices, of the form elucidated by Hall and Lakin (1988), for constrictions which have an appreciable region of local concave curvature upstream of the position at which separation occurs. The effect on the onset of separation due to the nonlinear Gortler modes will be discussed. A brief discussion of other possible nonlinear states which may also have a dramatic effect in delaying (or promoting) separation will be given.


Descriptors :   *VORTICES , *FLOW SEPARATION , *CHANNEL FLOW , STATIONS , REGIONS , CURVATURE , HEIGHT , REYNOLDS NUMBER , STEADY FLOW , CONSTRICTIONS , BOUNDARY LAYER FLOW , CHANNELS , ATTENTION , SEPARATION , FLOW , NUMBERS , NAVIER STOKES EQUATIONS


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE