<p>One of the key objectives in designing hydraulic structures is to minimise potential damage from complex or high-velocity flows. The design of flood spillways must consider the flow rates, velocities, and pressures involved. It's not possible to predict exactly the loads and stresses that will occur. Due to their size, full-scale prototypes can't be built or tested. While physical models have been used for years, numerical models have become increasingly important with rising computing power. However, these models need calibration and verification to be trusted. In this research project, both model types were compared for a specific flood spillway structure, a dam spillway with a pressure tunnel controlled by a radial gate. The discharge is diverted by a trajectory bucket (ski jump) and a plunge pool into the downstream water. The results from both models were compared and evaluated against established design approaches from the literature. The CFD software OpenFoam was used. The results showed good agreement between the models. Both types are valuable for designing and optimising such systems, each with strengths and weaknesses. These create opportunities for hybrid modelling, but the validity and scope of both models' results should always be critically assessed.</p>