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arXiv · 2006.13695

Resonances in pulsatile channel flow with an elastic wall

Duo Xu·Matthias Heil·Thomas Seeböck·Marc Avila
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Abstract

Interactions between fluids and elastic solids are ubiquitous in application ranging from aeronautical and civil engineering to physiological flows. Here we study the pulsatile flow through a two-dimensional Starling resistor as a simple model for unsteady flow in elastic vessels. We numerically solve the equations governing the flow and the large-displacement elasticity and show that the system responds as a forced harmonic oscillator with non-conventional damping. We derive an analytical prediction for the amplitude of the oscillatory wall deformation, and thus the conditions under which resonances occur or vanish.

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Duo Xu, Matthias Heil, Thomas Seeböck, Marc Avila. 2020-06-24. Resonances in pulsatile channel flow with an elastic wall. https://doi.org/10.1103/physrevlett.125.254501

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