TITLE:
Oil Streak Visualisation of Fluid Flow Over Single D-Type Cylinder
AUTHORS:
Astu Pudjanarsa, Herman Sasongko
KEYWORDS:
Cut Angle; Drag Force; Visualisation; Streamline
JOURNAL NAME:
World Journal of Mechanics,
Vol.2 No.4,
August
6,
2012
ABSTRACT: An experimental study on the effect of cut angle on circular cylinders to the drag force is performed. Six cylinders were cut at different angles and the air flow impinges perpendicular to the cut surface of the cylinder. The cut angles applied include: 0°, 30°, 45°, 53°, 55°, and 75°. The shear layer visualisation on the surface of cylinder was conducted as well. Drag force was measured using a wind tunnel force balance and the wind speed was set so that a corresponding Rey-nolds number of 5.3 × 104 was achieved. Visualisation was carried out by covering the cylinder with paper wetted by mixture of oil and titanium dioxide powder. Experimental results show that drag force has similar trend to that of previous experiment results. The minimum drag coefficient is attained at the cut angle of 53°. From oil streak visualisation the streamlines pattern of the flow over the cylinder could be reconstructed.