Wake angle for surface gravity waves on a finite depth fluid

Linear water wave theory suggests that wave patterns caused by a steadily moving disturbance are contained within a wedge whose half-angle depends on the depth-based Froude number F-H. For the problem of flow past an axisymmetric pressure distribution in a finite-depth channel, we report on the apparent angle of the wake, which is the angle of maximum peaks. For moderately deep channels, the dependence of the apparent wake angle on the Froude number is very different to the wedge angle and varies smoothly as LLC passes through the critical value LLC = 1. For shallow water, the two angles tend to follow each other more closely, which leads to very large apparent wake angles for certain regimes. (C) 2015 AIP Publishing LLC.