Fluid–structure interaction

Failing to consider the effects of oscillatory interactions can be catastrophic, especially in structures comprising materials susceptible to fatigue.

A reed actually produces sound because the system of equations governing its dynamics has oscillatory solutions.

The interaction between tribological machine components, such as bearings and gears, and lubricant is also an example of FSI.

[7] In addition to pressure-driven effects, FSI can also have a large influence on surface temperatures on supersonic and hypersonic vehicles.

[9] Failure to take into account this property of blood vessels can lead to a significant overestimation of resulting wall shear stress (WSS).

This is significant because incorrect modeling of aneurysms could lead to doctors deciding to perform invasive surgery on patients who were not at a high risk of rupture.

On the other hand, development of stable and accurate coupling algorithm is required in partitioned simulations.

Interface Newton–Raphson methods solve this root-finding problem with Newton–Raphson iterations, e.g. with an approximation of the Jacobian from a linear reduced-physics model.

[28] If the interaction between the fluid and the structure is weak, only one fixed-point iteration is required within each time step.

These so-called staggered or loosely coupled methods do not enforce the equilibrium on the fluid–structure interface within a time step but they are suitable for the simulation of aeroelasticity with a heavy and rather stiff structure.

[31][32][33] Modarres-Sadeghi, Yahya: Introduction to Fluid-Structure Interactions, 2021, Springer Nature, 978-3-030-85882-7, http://dx.doi.org/10.1007/978-3-030-85884-1 Introduces the subject of Fluid-Structure Interactions (FSI) to students and professionals and discusses the major ideas in FSI with the goal of providing the fundamental understanding to the readers who possess limited or no understanding of the subject.