22nd Congress of International Council of the Aeronautical Sciences, Harrogate, UK, 28 August - 1st September, 2000
Paper ICAS 2000-2.9.3

EXPERIMENTAL INVESTIGATION OF THREE DIMENSIONAL SEPARATED FLOW OVER A BODY OF REVOLUTION AT HIGH ANGLES OF ATTACK

T. Ishide (1), N. Nishikawa (2), F. Mikami (2)
(1) Kisarazu National College of Technology, Japan; (2) Chiba University, Japan

Keywords: separated flow , laser light sheet method , smoke visualization technique

The flow in the cross-flow separation of an axisymmetric paraboloid at 30, 40 and 50 deg angle of attack has been investigated experimentally by smoke visualization technique and hot wire anemometer. Reynolds numbers are 9.0×103 and 1.8×104 referred to the base diameter. Laser light sheet method is used in studying the structure of the vortices in cross-sectional flow. The development of streamwise vortices in each section of the body is visualized. X-type probe was used to measure three dimensional velocity fields over the axisymmetric paraboloid. Velocity fluctuations at sampling time of 4kHz have been also evaluated. The extent of longitudinal vortices, such as main-, primary- and secondary vortices, and the change of r.m.s. value in various cross-sections are presented. The variation of vortex patterns is shown for each cross-section, angle of attack and Reynolds number. It has been confirmed that each streamwise vortex is related to the velocity fluctuations.

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