Wavy Motion of a Wall

Wall Wavy Motion CFD Simulation, Dynamic Mesh, ANSYS Fluent

Description

This project simulates flow behavior within a channel featuring a non-stationary, wavy bottom wall using ANSYS Fluent's dynamic mesh capabilities. The 2D channel geometry was designed in Design Modeler and meshed in ANSYS Meshing using an unstructured grid, with mesh quality specifically optimized to support the dynamic deformation required by this simulation.

Methodology

The dynamic mesh model governs the wavy wall's motion, implemented through a Grid Motion UDF that prescribes the wall's oscillating displacement over time. The mesh zone directly above this non-stationary wall was assigned the Deforming option, allowing it to continuously adjust as the wall moves through its wave cycle. Given the inherently time-dependent nature of this wave-induced flow, the simulation was configured as transient, with solver settings and time-stepping strategy tuned to maintain both accuracy and stability throughout the deforming-mesh solution process.

Conclusion

The results capture how the channel's continuously changing cross-section — driven by the wavy wall's motion — shapes the resulting velocity and pressure fields over time. Time-varying pressure and velocity contours, along with accompanying animations, reveal the close coupling between the wall's oscillation and the flow's evolving behavior: as the wall's wave motion narrows and widens the channel cross-section, velocity and pressure respond correspondingly, producing a clear, time-dependent flow pattern directly tied to the prescribed wall movement. These results illustrate the core mechanics of dynamic-mesh-driven wave propagation in a bounded channel, providing a foundation for analyzing similar non-stationary boundary problems in hydraulic and fluid-structure interaction applications.