Mechanism of structure formation in circular hydraulic jumps: numerical studies of strongly deformed free-surface shallow flows

We studied numerically circular hydraulic jumps of moderate Reynolds number to clarify the structure formation in circular hydraulic jumps. The numerical model has been constructed based on the CIP–CUP (cubic interpolated propagation–combined unified procedure) method, the level set method and the CSF (continuum surface force) model. The model can simulate strongly deformed interfaces as those found in hydraulic jump phenomena. In this study, we found that the pressure deviation from the hydrostatic equilibrium around the hydraulic jump is essential for the structure formation and that the surface tension plays an important role for the establishment of the pressure deviation.