no disagreement, just trying to add
Yeah on the wavelength-depth thing. I was just giving the simplest answer and wasn’t specific enough. No, the wave will not necessarily break at a depth of 1/10th wavelength. That’s just a rule of thumb for a wave entering shallower water. It either breaks or becomes a shallow water wave somewhere near that depth/wavelength ratio. The speed of the wave (is proportional to wavelenght), angle relative to the bottom contours, shape of the bottom, steepness of the slope, all affect whether the wave breaks or not and the shape of the wave when it breaks.
I wasn’t disagreeing. I thought I was adding. It is interesting to me to consider the behavior of waves as they encounter shallow water when thinking about the behavior of a canoe or kayak encountering shallow water.
thanks, I was looking for that
I tried to describe the change in wavemaking that occurs in my earlier post when I mentioned the change in the shape of the wake created but Mr. Winters does a better job.
“”"“and water depth) the bow wave system takes on a concave shape (radiating from the bow and when viewed from above) roughly at right angles to the direction of travel. The speed at this point is aproximately Froude Number 0.99 with the wave traveling at the same speed as the boat and the wave-making effect concentrated in one wave. With additional power (creating a speed of aproximately Froude Number 1.4), the wave pattern changes to one of diagonal waves only (convex when viewed from above radiating from the bow) and the resistance falls to levels below that in deep water.”""""
That transverse wave that is propogating out at right angles to the direction of travel is neat unless you’re the engine making it. My lake is fairly shallow. One day a yacht pushed me 2000m in about 7:20 in my k1. I was about 30m to his starboard and stayed in front of him the whole way. I actually wasn’t working that hard. He couldn’t understand how I stayed in front of him. He had the Detroits gagged and the harder those Diesels gagged the better ride I got. He had no clue that his 40ton vessel was producing that wave.
There’s a great graphic of the effect somewhere I’ll post if I can find it.