AN EXPERIMENTAL STUDY OF FLOW AROUND SURFACE-MOUNTED PYRAMIDS Background Flow around surface-mounted pyramids is of great engineering and fundamental importance. It represents the flow around mountains, hills, buildings and electronic components. Objective Different experimental methods were used to measure velocity and pressure fields, as well as to visualize the flow, in order to characterize the flow field. Vortex shedding from a pyramid (top). Formation of the horseshoe vortex upstream of the pyramid (lower).

3-D presentation of the vortical structures around a pyramid Research Carried Out Velocity Field from: PIV (Particle Imaging Velocimetry) LDV (Laser Doppler Velocimetry) HWA (Hot Wire Anemometry) Pressure Field Oil-Film Visualization Smoke In Laser Sheet LIF (Laser Induced Fluorescence) in Water Oil-film image and pressure contours (left), PIV velocity field (right) around pyramid (apex angle,  = 60°, angle of attack = 0°) Key Findings Periodicity in the wake of slender pyramids (15°<<75°), due to regular vortex shedding. Wind loading on the pyramid is independent of the orientation. A new length scale for the ground pressure profiles around pyramids and other bluff bodies. 3-D presentation of the vortical structures around a pyramid