Generalised hydraulic rise over a rectangular disturbance in open channel flow

Two-dimensional free-surface flow over a rectangular obstacle in the channel bottom is considered. Generalised hydraulic rise solutions (uniform supercritical flow upstream and a train of waves downstream) are examined using the forced Korteweg-de Vries model. A recently developed technique is employed to consider all solutions in the infinite family of generalised hydraulic rises simultaneously. The effect of the height and length of the disturbance on the solution space is considered, focussing on the smallest and largest waves as well as the locations of the special, waveless, hydraulic rise solutions. All solution types are mapped in the topographic parameter space. The behaviour of the solutions is then examined in the fully nonlinear potential flow model using established boundary integral methods.