Dynamics of Multiple Cantilever Plates Mounted on a Cavity Wall Under Natural Convection

This study numerically investigates the dynamics of multiple elastic cantilever plates mounted on one vertical wall of a square cavity subjected to natural convection. The cavity has adiabatic vertical walls, a stationary cold top wall, and a heated bottom wall, establishing a buoyancy-driven flow. The flexible plates are considered isothermal, and their interactions with the thermal flow field are simulated using the open-source multiphysics solver SU2. The effects of key non-dimensional parameters—Rayleigh number (Ra), Cauchy number (Ca), and mass ratio (β)—are examined to understand their influence on plate oscillations and flow behavior.

The results show that the natural convective flow induces rich dynamical responses, including steady, periodic, quasi-periodic, and chaotic flapping modes. The presence of multiple cantilevered plates leads to out-of-phase oscillations and intricate vortex–structure interactions within the cavity. Increasing Ca enhances oscillation amplitude and nonlinear effects, while higher Ra intensifies buoyancy-driven instabilities. This work provides new insights into multi-plate fluid–structure interactions in natural convection, emphasizing the influence of thermal forcing and geometric configuration on instability and dynamic behavior.