Vahid Tamimi - master of science - k.N Toosi university
Mostafa Zeinoddini - Associate professor - k.N Toosi university
Mohammad saeed Seif - Professor - Sharif university of technology

In many practical situations, the cylinders are found in a specific arrangement and have different transverse vibration response from isolated cylinders. In the most simplified case one can consider two rigid circular cylinders with the same diameter in tandem arrangement. In this simple configuration the upstream cylinder is fixed and the downstream cylinder is flexibly mounted. In the present study the cross flow and inline vibration amplitudes of two uniformcircular cylinders in tandem arrangement are presented. The single degree of freedom vibrating system (i.e. the downstream cylinder either in transverse or stream-wise directions) has a low mass-damping parameter (m*x » 0.0402 ). The Reynolds number ranges from 2,800 to 28,000and the reduced velocities vary from 1 to 21. Various separations (S/D) from 2 to 5 are studied. The trailing cylinder oscillation at S/D=3,4 presents what previous researchers have termed interference galloping behavior. These initial results validate the experimental set-up and lead the way for future work

Experimental study, VIV, WIV, Cross flow and inline vibrations, Tandem arrangement