ONR studying wave pressure on high-speed planing hull to reduce structural weight

31 May 2015 (Last Updated May 31st, 2015 18:30)

US Office of Naval Research (ONR) scientists have conducted experiments, using boats with high-speed planing hulls, to understand the motions, forces, and pressures generated by waves on boats.

planing hull

US Office of Naval Research (ONR) scientists have conducted experiments, using boats with high-speed planing hulls, to understand the motions, forces, and pressures generated by waves on boats.

Planing hulls are designed to produce a lift, allowing the boat to glide on top of the water, skimming quickly over its surface.

ONR sea warfare and weapons department programme officer Dr Bob Brizzolara said: "When a hull is going at speed and it hits a wave, it's like hitting a wall. It's a violent collision, and the forces are very large.

"This causes injuries to sailors, commonly back and leg injuries, and also can degrade the structure of the vessel."

Known as wave slam, this process will see the boat rise to the top of the wave when the crests of the waves are high, and fall back down to the wave's trough with great force.

"When a hull is going at speed and it hits a wave, it's like hitting a wall. It's a violent collision, and the forces are very large."

The US Naval Academy, the University of Iowa, and ONR, working with Naval Surface Warfare Center (NSWC) Carderock Division, are attempting to minimise hull weight, while maintaining structural adequacy.

Brizzolara added: "We're working to understand the pressures on the hull that are due to the wave slamming, since right now, they are not well understood.

"We'd like to be able to save weight in the structure so we can carry more fuel and payload, but we don't understand those pressures well enough to be able to start taking weight out of the structures."

The scientists are carrying out the research in two parts, experimentally with scale models, and using computer simulations.


Image: Scientists are working to understand the pressures on the hull that are due to the wave slamming. Photo: courtesy of Office of Naval Research.