Accession Number : ADA215689

Title :   Appendage Flow Computations Using the INS3D Computer Code.

Descriptive Note : Final rept.,

Corporate Author : DAVID TAYLOR RESEARCH CENTER BETHESDA MD

Personal Author(s) : Ohring, Samuel

Report Date : OCT 1989

Pagination or Media Count : 105

Abstract : The INS3D code, a steady-state incompressible, fully three-dimensional Navier-Stokes solver, was applied to the computation of flow past an appendage mounted between two parallel flat plates of infinite extent at a Reynolds number of one-half million. The Baldwin-Lomax turbulence model was used to compute the eddy viscosity. The appendage consisted of a 1.5:1 elliptical nose and a NACA 0020 tail joined at maximum thickness of 0.24 chordlengths. A detailed description of the flow results covers all the major features of appendage flow and the results, for an unfilleted appendage, are in general agreement with experimental and other numerical results, except that the lateral location of the horseshoe vortex is larger than that in the experimental results. A detailed description, not found in other papers, is presented of the important trailing edge vortex. Detailed results for a second flow case, in which filleting is applied mainly to the front and side of the aforementioned appendage, show a greatly weakened horseshoe vortex but a still significant trailing edge vortex, that prevented velocity-deficit reduction in the wake, compared to the unfilleted appendage flow case. The calculations for the filleted case also exhibited an upstream instability. The plotting program PLOT3D was used to obtain color photos for flow visualization. (RRH)

Descriptors :   *APPENDAGES, *COMPUTATIONS, *EDDIES(FLUID MECHANICS), *FLOW VISUALIZATION, *TRAILING EDGES, *TRAILING VORTICES, COLORS, FLAT PLATE MODELS, FLOW, NAVIER STOKES EQUATIONS, NUMERICAL ANALYSIS, PARALLEL ORIENTATION, PHOTOGRAPHS, STABILITY, THREE DIMENSIONAL, VISCOSITY, VORTICES, WAKE.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE