VELOCITY MEASUREMENTS ON FLOW AROUND A CYLINDER
ABSTRACT: If the
cylinder is set in an open
channel, the flow
upstream will undergo
a separation of
the turbulent boundary layer and rolls up to form the
well-known horseshoe-vortex system,
which is swept around the cylinder. The flow fields around a cylinder
positioned normal to the flow in an open channel have been investigated experimentally
for two types of flow. An Acoustic Doppler Velocity Profiler was used to obtain
instantaneously the three directions of the velocity in the flow. Results of
the experiments present the vertical velocities distributions of the flow
around a cylinder, showing a highly three-dimensional picture, being reasonably
organized in the front and less organized in the back of the cylinder, where
flow separation takes place. It also shows that a horseshoe-vortex system is
established, existing of a measurable vortex with underneath a return flow.
The system develops itself in
the upstream corner at the nose
of the cylinder and stretches around towards the downstream.
Author: Bambang Yulistiyanto
Journal Code: jptsipilgg090011
