# Modeling and Simulation of a Fluttering Cantilever in Channel Flow

## TL;DR

This paper develops a coupled fluid-structure model for a fluttering cantilever in channel flow, validating it against simulations and exploring its accuracy across various parameters, with implications for energy harvesting and biomedical applications.

## Contribution

The paper introduces a new coupled fluid-structure model for viscous channel flow that accurately predicts flutter boundaries over a wide parameter range, extending beyond previous models.

## Key findings

- Model accurately predicts flutter boundaries within valid parameter ranges.
- Model predictions converge to inviscid results at high Reynolds numbers.
- Validation against DNS confirms model's applicability for small channel heights.

## Abstract

Characterizing the dynamics of a cantilever in channel flow is relevant to applications ranging from snoring to energy harvesting. Aeroelastic flutter induces large oscillating amplitudes and sharp changes with frequency that impact the operation of these systems. The fluid-structure mechanisms that drive flutter can vary as the system parameters change, with the stability boundary becoming especially sensitive to the channel height and Reynolds number, especially when either or both are small. In this paper, we develop a coupled fluid-structure model for viscous, two-dimensional channel flow of arbitrary shape. Its flutter boundary is then compared to results of two-dimensional direct numerical simulations to explore the model's validity. Provided the non-dimensional channel height remains small, the analysis shows that the model is not only able to replicate DNS results within the parametric limits that ensure the underlying assumptions are met, but also over a wider range of Reynolds numbers and fluid-structure mass ratios. Model predictions also converge toward an inviscid model for the same geometry as Reynolds number increases.