Experimental investigation of a three dimensional boundary layer flow in the vicinity of an upright wall mounted cylinder
The flow of a three-dimensional boundary layer approaching an upright wall-mounted circular cylinder has been experimentally investigated by means of wet-surface visualization techniques and time-resolved measurements of the wall pressure: the gradient of which is related to the vorticity flux away from the wall. A separation line which marks the horse-shoe vortex, emerges from the mean separation point and wraps the cylinder with a parabola-like line. Measurements obtained at the separation point and its close vicinity indicate a minimization in mean presure, a two-fold increase in values of root mean square of pressure fluctuations, a fuller lower frequency content of spectra, low degree of space-time correlations at adjacent positions and a longer integral time scale. A bimodal pdf of the fluctuating pressure was found in the vicinity of the mean separation point, close to the corner region and in the wake of the cylinder. A peak in the power spectra, associated with a quasi-periodic vortex shedding from the cylinder, was sensed even at 1.417 diameters upstream.
AIAA, Fluid Dynamics, 21st Plasma Dynamics and Lasers Conference, 21st, Seattle, WA, June 18-20, 1990. 17 p.
- Pub Date:
- June 1990
- Boundary Layer Flow;
- Flow Distribution;
- Three Dimensional Boundary Layer;
- Boundary Layer Separation;
- Circular Cylinders;
- Flow Geometry;
- Interactional Aerodynamics;
- Fluid Mechanics and Heat Transfer