A single mean roughness value can conceal hydrodynamically important spatial variation. This work quantifies how different roughness distributions with the same area-averaged equivalent roughness alter resistance, boundary-layer development, and wake structure. Current work examines full-scale powering prediction using effective roughness descriptors and measurement-informed spatial distributions.

Added-resistance predictions can vary substantially across CFD setups, particularly at specific wavelength ratios. This project examines that sensitivity through a structured parameter study to identify modelling choices that contribute to the variation and to assess approaches for more reproducible added-resistance prediction.