Aerospace and Ocean Engineering (ABSTRACT)A three dimensional, pressure driven turbulent boundary layer created by an idealized wing-body junction flow is experimentally studied. The body used is a 3 : 2 elliptical nosed NACA 0020 tailed symmetric profile which has a chord length of 30.5 cm (12 inches), maximum thickness of 7.17 cm (2.824 inches) , heigth of 22.9 cm (9.016 inches). The body was sitting on a flat plate. The nominal reference velocity of the flow is 27 m/sec and the Reynolds number based on the momentum thickness at 0.75 chord upstream of the body on the centerline of the tunnel is~ 5936. The data presented include time-mean static pressure, skin friction magnitude and direction on the wall, as well as the mean velocity and all Reynolds stresses at several stations on a line dete~ed with the mean velocity vector component parallel to the wall in the layer where the u 2 normal stress is maximum. The mean velocity and stress data were obtained both with hot-wire ( HW ) and laser-Doppler-velocimeter ( LDV ) techniques. The LDV measurements were taken twice due to the differences observed between the HW and LDV data, which is also shown with the present study. This gave a chance to study the uncertainties on the mean velocity and the stresses extensively. Pressure distributions on the wing and the on the bottom plate were obtained with a Scanivalve and an inclined manometer. Skin friction vectors at several locations on the wall were measured in another study done by Allinger ( 1990 ) with a laser interferometer technique. The data show that the eddy viscosity of the flow is not isotropic, but the ratio of eddy viscosities perpendicular and parallel to the direction of the mean velocity vector component parallel to the wall at the point in the layer where u 2 is maximum is close to unity, and the shear-stress vector Several fellow students and research associates need to be thanked. I would like to thank especially to Dr. Naval K. Agarwal for being friendly and helpful, even in personal problems, and to Dr.William J. Devenport for preparing much of the instrumentation that I used in the research.Patience of a good friend, Fei T. Kwok, in proof reading my entire dissertation is unforgettable. I would like to thank to Seungki Ahn, Kevin A. Shinpaugh, and Richard B. Mays for being friends. Figure 59a. N, anisotropy constant computed using LDV data in tunnel coordinates. 254 Figure 59b. N, anisotropy constant computed using LDV data in tunnel coordinates. 255 Figure 59c. N, anisotropy constant computed using LDV data in tunnel coordinates. 256 Figure 60a. N, anisotropy constant computed using LDV data in free-stream coordinates. 257 Figure 60b. N, anisotropy constant computed using LDV data in free-stream coordinates. 258 Figure 60c. N, anisotropy constant computed using LDV data in free-stream coordinates. 259 Figure 6 la. N, anisotropy constant computed using LDV data in maximum normal stress coordinates. Figure 62a. Al, Townsend's structural parameter computed using LDV data. ...
