DEPARTMENT OF AEROSPACE AND OCEAN ENGINEERING Steady Flow Over a 6:1 Prolate Spheroid

 

ABSTRACT

Velocity measurements were carried out on the lee-side of a 6:1 prolate spheroid, Re_L= 4.2´10⁶, at 10° and 20° angles of attack(a), and at x/L= 0.600 and 0.772.  The dominant feature of each of these flowfields is the presence of a shed vortex due to cross-flow separation.  This is a source of considerable noise and vibration.  At a = 10°, high turbulence levels is confined to the near-wall region.  At a= 20°, the highest turbulence levels were measured away from the wall at azimuthal (f) locations where the flow is separating.  Velocity spectra for regions with weaker 3-D effects exhibit features that are observed for equilibrium flows.  Spectra in strong vortical flow regions show unusual and apparently non-equilibrium behavior.  This behavior has some qualitative similarities with the surface pressure fluctuation spectra .
 
 

	Goody, M. C., Simpson, R. L., Engel, M., Chesnakas, C. J., and Devenport, W. J., 1998,"Mean Velocity and Pressure and Velocity Spectral Measurements within a Separated Flow Around a Prolate Spheroid at Incidence," AIAA Paper 98-0630
	Chesnakas, C. J., Simpson, R. L., and Madden, M. M., 1993, "Three Dimensional Velocity Measurements on a 6:1 Prolate Spheroid," Data Report VPI-AOE-202, Dept. of Aero & Ocean Engr, VPI&SU, Blacksburg, VA
	Chesnakas, C. J., and Simpson, R. L., 1994, "Full Three-Dimensional Measurements of the Cross-flow Separation Region of a 6:1 Prolate Spheroid," Experiments in Fluids, Vol. 17, pp. 68-74.
	Chesnakas, C. J., and Simpson, R. L., 1996, "Measurements of the Turbulence Structure in the Vicinity of a 3-D Separation, " Journal of Fluids Engineering, Vol. 118, No. 1, pp. 268-275.
	Chesnakas, C. J., and Simpson, R. L., 1997, "A Detailed Investigation of the 3-D Separation about a 6:1 Prolate Spheroid at Angle of Attack," AIAA Journal, Vol. 35, No. 6, pp. 990-999.
	Wetzel, T. G., 1996, "Unsteady Flow Over a 6:1 Prolate Spheroid," Ph.D Dissertation, Dept. of Aero & Ocean Engr, VPI&SU, Blacksburg, VA.   DATA AVAILABLE ON WEB

 

The following files contain LDV and hot-wire velocity measurements of the flow about a 6:1 prolate spheroid at incidence. The *.XLS files are Microsoft Excel workbook files. Some additional flow documentation is given in the *.PDF file as indicated below.  You will need the Adobe Acrobat Reader in order to read the *.PDF file.  The Adobe Acrobat Reader is available from Adobe free of charge by clicking on this link: Get Acrobat Reader .

NOTE:  THE OUTER LAYER BOUNDARY LAYER VARIABLES (d^*, q, U_e) GIVEN HERE SUPERCEDE THE VALUES POSTED IN THE JOURNAL OF FLUIDS ENGINEERING DATABANK

Flow about the Leeside of a 6:1 Prolate Spheroid at Angle of Attack

Flow Documentation  (DOC.PDF : 33 KB)

Contains relevant boundary layer parameters (e.g. flow velocity, boundary layer thickness, etc.)

Data Files

    a = 10°, x/L = 0.600 (16V.XLS : 161 KB)

    a = 10°, x/L = 0.772 (17V.XLS : 226 KB)

    a = 20°, x/L = 0.600 (26V.XLS : 232 KB)

    a = 20°, x/L = 0.772 (27V.XLS : 236 KB)