Experimental hydrodynamic study of the Qiantang River tidal bore

To study the hydrodynamics of tidal bore, a physical modeling study is carried out in a rectangular flume with considerations of the tidal bore heights, the propagation speeds, the tidal current velocities, the front steepness, and the bore shapes. After the validation with the field observations, the experimental results are analyzed, and it is shown that: (1) the greater initial ebb velocity or the larger initial water depth impedes the tidal bore propagation, (2) the maximum bore height appears at an initial ebb velocity in the range of 0.5 m/s–1.5 m/s, (3) when the Froude number exceeds 1.2, an undular bore appears, after it exceeds 1.3, a breaking bore occurs, and after it exceeds 1.7, the bore is broken.