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Vortex-induced vibration (VIV) is a phenomenon that occurs when cylindrical structures are
subjected to fluid flow. This phenomenon has significant implications in various engineering
fields. One notable example is its impact on the offshore riser tubes dynamics used for extracting
seabed oil from deep water conditions, where depths of water can reach at 3000 m. Understanding
VIV is crucial for the design of such riser systems. Moreover, VIV plays a vital role in other
engineering applications at offshore, including mooring lines for offshore floating wind turbines,
underwater pipelines, and flexible slender piping’s.
When underwater structures exposed to marine currents are susceptible to VIV arises by the
oscillatory forces generated due to vortex shedding flow dynamics. This study specifically focuses
on investigating the VIV of rotating cylinder in direction stream wise subjected to oscillatory flows.
In that study the flow-induced vibration around the rotating cylinder is examined using numerical
simulations of two-dimensional. Fluid flow around cylinder is analysed using “Arbitrary
Langrangian-Eulerian (ALE) scheme along with Petrov-Galerkin (P-G) Finite Element” method
in which fluid structure interactions were deeply examined, along with flow behaviour, ratio of
amplitudes and vortex shedding patterns were analysed. The proposed investigation is carried out
at 150 Reynolds number with 2 mass ratio and zero damping ratio. Oscillatory flow condition is
modelled in numerical simulation using two Kuelegan carpenter numbers, KC=05 and KC=10,
with broad range of reduced velocities from 1-20 selected. This research study examines the
rotation effects on the flow around on elastically mounting rotating cylinder when flow direction
is stream-wise. It is observed during the course of cylinder, along with the KC number and Vr,
significantly affects the amplitude of vibration. Cylinder rotations rate is defined by α = ωD/2U
where ω is angular velocity of the cylinder. It is kept in a broad range of α=
(0.2,0.3,0.4,0.5,0.6,0.7,0.9 & 1) to analyse the cylinder behaviour in oscillatory flow. It was found
that the amplitude response of cylinder displacement is directly linked with cylinders’ rotation
rate. The peak amplitude response for this present study would occur at the lock-in regime where
cylinder vibration approaches to the oscillatory flow frequency. Furthermore, this research
includes a comprehensive examination of flow structure to enhance the understanding of the
rotational cylinder's underlying physics. The research concluded that when rotation rate increases
it would yield rise in amplitude response of cylinder displacement and lock-in regime.