Wake angle for surface gravity waves on a finite depth fluid

Abstract

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 $F_H$ passes through the critical value $F_H=1$. For shallow water, the two angles tend to follow each other more closely, which leads to very large apparent wake angles for certain regimes.

7 pages, 4 figures, accepted for publication by Physics of Fluids

References in corpus (5)

• What is the apparent angle of a Kelvin ship wave pattern?
• Mach-like capillary-gravity wakes
• Wake pattern and wave resistance for anisotropic moving objects
• Scaling of far-field wake angle of non-axisymmetric pressure disturbance
• Jacobian-free Newton-Krylov methods with GPU acceleration for computing nonlinear ship wave patterns