Flow-induced vibration suppression for a single cylinder and one-fixed-one-free tandem cylinders with double tail splitter plates

Abstract

In this paper, double tail splitter plates (DTSPs) have been investigated to suppress the flow-induced vibrations (FIVs) of both an elastically mounted single circular cylinder and one-fixed-one-free tandem cylinders in a wind tunnel at Re = 4000-48000. The splitter plates length to diameter ratios, L/D, were set from 0.4 to 2.0 and the angles​ θ between them were set from 0°-90°. The amplitudes of single cylinders with DTSPs exhibit three vibration patterns: VIV (vortex-induced vibration) pattern, galloping pattern and suppressed pattern, and four patterns of vortex shedding frequencies fs can be classified. The optimal suppression efficiency is 97.6% occurred at θ = 90°, L/D = 2.0. For the one-fixed-one-free tandem arrangement cylinders, comparing to the single one, the DTSPs have a better applicability to suppress the vibration, and all the downstream cylinders present a suppressed pattern except for the case of L/D = 0.4 at θ = 0°. The best suppression efficiency is 98.4% occurred at θ = 60°, L/D = 0.8. Different from fs can be locked to multiple harmonics of natural frequencies fn, the oscillation frequencies can be only locked to the first harmonic of fn.