Assessment of a Single‐Phase Dynamic‐Boundary CFD Approach for Wave‐Induced Unsteady Aerodynamics

ABSTRACT

This study presents a validated numerical framework for predicting unsteady aerodynamic loads induced by prescribed moving boundaries using a single‐phase computational fluid dynamics (CFD) approach. Rather than explicitly resolving an air–water interface, wave‐induced effects are represented through time‐dependent deformation of a solid lower boundary within an incompressible air‐only domain. The methodology is implemented in OpenFOAM using dynamic mesh motion and is evaluated for an airfoil operating in ground effect above mechanically generated waves. Numerical predictions are compared against experimental force measurements from the DARPA Wing Over Water campaign and against corresponding two‐phase volume‐of‐fluid simulations. Results show that the single‐phase dynamic‐boundary approach accurately captures the dominant unsteady lift and drag trends, including frequency and phase behavior, while providing improved numerical robustness and substantially reduced computational cost. Although localized nonlinear effects and force amplitudes are attenuated under steep wave conditions, the framework offers a practical and scalable surrogate for fully coupled multiphase simulations. The study provides quantitative guidance on the applicability and limitations of dynamic‐boundary single‐phase CFD for wave‐influenced aerodynamic flows, supporting its use in engineering analysis and parametric studies.