Drag Coefficients of a Long Flexible Circular Cylinder with Wake Interference

• Published in: Volume 5: Polar and Arctic Sciences and Technology; CFD and VIV
• Main Author: Huera-Huarte, Francisco J.
• Format: Book Part
• Language: unknown
• Published: American Society of Mechanical Engineers 2009
• Subjects: Arctic
• Online Access: https://doi.org/10.1115/OMAE2009-79099

Drag coefficients of the downstream cylinder in a tandem arrangement of two models aligned with the flow are shown in this work. The models, which experienced vortex-induced vibrations with wake interference, had an external diameter of 16 mm and a total length of 1.5 m giving an aspect ratio of about 94. More than 400 runs were carried out in a water flume with only the lower 40% of the models exposed to the current. The flow speed was varied up to 0.75 m/s giving Reynolds numbers in the range from 1200 to 12000. A supporting structure. where the models were attached. allowed changes in the centre to centre distances and in the applied top tensions. Separations of up to 4 diameters were tested with tension variations from 15 to l10 N. Reduced velocities based on the fundamental natural frequency reached values up to 16. The mass ratio of the models was around 1.8 and the combined mass-damping parameter about 0.05. © 2009 ASME. Special thanks are due to Prof. P. W. Bearman and the Department of Aeronautics of Imperial College London. Funding provided by Universitat Rovira i Virgili through grant 2006AIRE-03 is gratefully acknowledged. The author is a Marie Curie Postdoctoral Research Fellow funded by the European Commission (PIOF-GA-2008-219429). Published - HueraHuarte2009p11814Omae_2009_Vol_5.pdf