Active noise control allows you to cancel dominant frequencies in noise cancelling headphones by playing the inverse wave. Given the speed of GPUs and evolutionary computation, could you use sensors a few feet in front of a boat to measure waves and generate an inverse wave in real time that would cancel the waves for just an inch in front of the bow? So from the bow's perspective it was just sailing through calm water. I know there are waves coming across other parts of the hull and it might require a lot of energy to cancel waves in front of the boat. But assuming you could calculate the correct inverse wave to produce in real time, how would that impact the energy efficiency of the boat.
Hi Brendan, very interesting question, sorry for the late reply but I just noticed it today. I work in hydrodynamics but I am not an expert of control systems. I'll try to answer anyways. That is a very good idea. In practice, however, real water waves are usually a random process, so you don't have "a wave", but a superimposition of different wave forms. I think this could make the cancelling wave generation a bit harder from a practical point of view... I am also aware of some other techniques which allow to cloak a floating body, i.e. to make it invisible to incoming waves. Though different than what you propose, maybe these techniques could allow to get a similar effect. Cheers.
Brendan,
The idea you have is the same which led naval architecs to install a bulb at the bow of big ships. If you see the bulb as say, a sphere travelling ahead of the ship at the same velocity, you can consider that there are to systems of waves interfering: ship wave system and the bulb wave system. by design optimization , architects manage to have a certain amount of reduction of the ship wave system by the bulb wave system. a kind of positive interference, which works fine at a given constant speed (big ships are designed for a given operating speed)
This may not be related, but may be of interest:
https://www.youtube.com/watch?v=Yq-xy9GOmo0
http://sffe.no/colloquia/arkiv/130129_BoeckmannWindWavePropulsion.pdf
http://www.marinepropulsors.com/proceedings/2013/11B.2.pdf
- Badges
- Science topic
- Similar topics
- Engineering
- Electrical Engineering
- Signal Processing