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Article: Viscous Theory for the Vibrations of Coaxial Cylinders: Analytical Formulas for the Fluid Forces and the Modal Added Coefficients

This article addresses the small-amplitude forced beam vibrations of two coaxial finite-length cylinders separated by a viscous Newtonian fluid. A new theoretical approach based on an Helmholtz expansion of the fluid velocity vector is carried out, leading to a full analytical expression of the fluid forces and subsequently of the modal added mass and damping coefficients. Our theory shows that the fluid forces are linear combinations of the Fourier harmonics of the vibration modes.

Article: Modal added-mass matrix of an elongated flexible cylinder immersed in a narrow annular fluid, considering various boundary conditions. New theoretical results and numerical validation

This paper considers the fluid–structure interaction problem of two coaxial cylinders separated by a thin layer of fluid. The flexible inner cylinder is imposed a small amplitude harmonic displacement corresponding to a dry vibration mode of an Euler–Bernoulli beam, while the external cylinder is rigid. A new theoretical formulation based on the assumption of a narrow fluid annulus is derived to estimate the modal added-mass matrix of the vibrating cylinder.

Article: Hydrodynamic Interaction Between Two Flexible Finite Length Coaxial Cylinders: New Theoretical Formulation and Numerical Validation

This article addresses the interaction of two coaxial cylinders separated by a thin fluid layer. The cylinders are flexible, have a finite length, and are subject to a vibration mode of an Euler–Bernoulli beam. Assuming a narrow channel, an inviscid and linear theoretical approach is carried out, leading to a new simple and tractable analytical expression of the fluid forces.

Article: New estimations of the added mass and damping of two cylinders vibrating in a viscous fluid, from theoretical and numerical approaches

This work deals with the small oscillations of two circular cylinders immersed in a viscous stagnant fluid. A new theoretical approach based on an Helmholtz expansion and a bipolar coordinate system is presented to estimate the fluid forces acting on the two bodies. We show that these forces are linear combinations of the cylinder accelerations and velocities, through viscous fluid added coefficients. To assess the validity of this theory, we consider the case of two equal size cylinders, one of them being stationary while the other one is forced sinusoidally.

FIV 2022 - call for papers at :

Greetings everybody


Almost everything is in the title, here are some extra details. The salient point is that the paper submission is now open, and we warmly encourage you to have students and colleagues attend the conference by submitting new (or delayed) papers.


The deadline for submission is the 15th of April. 


New article on wrinkling

Curvature-induced symmetry breaking determines elastic surface patterns

New iMechanica member

Dear colleagues,

First time in iMechanica. As a presentation, I am a researcher interested in Fluids and Solids Mechanics. My approach to research involves an interplay between experimental, theoretical and numerical modeling techniques. My principal research areas might be categorized as: Fluid-Structure-Thermal Interaction, Aeroelasticity, Material Resistance, Rotating flows, Mechanical Instabilities.

My home page for more informations:

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