How would you build a water pump...

[Externet]

A water pump, probably piston driven, that left floating at the side of an anchored boat, would use small 10 cm crest-to-valley waves to pump water 5 metres high to a reservoir in the boat with a 3mm hose ? -Nothing attached to the boat hull, that would be easy-

 

A submerged 'umbrella' and a float, connected by piston/cylinder assembly ?

A hinged float ?

 

The flow can be small, but could it be made to rise 5m ?

[CaptainPanic]

So, you want to use the 10 centimeter waves to power a pump to pump water to 5 meters high?

 

To "convert" the 10 centimeter difference in height to 5 meters, you need a factor 50 in pressure difference. Therefore, if you have a certain surface that goes up and down with the waves, your internal diameter of the pipe going 5 meters up must be 50 times smaller. (And that is not yet including losses due to any friction or other losses).

 

Keep in mind that the waves are already small (the 10 centimeter height difference is only reaches at the top of the wave, which is a really small surface area).

 

I have no good suggestions for a friction free system... some lever system that pushes on the piston perhaps?

[npts2020]

Waves automatically bring ratcheting to my mind. You could use the paddlewheel from a riverboat (or something similar) with a ratchet. Orient the paddlewheel in the direction of the waves and each wave will give you a push with the ratchet keeping you from losing energy on the return. Attach that to any kind of pump you want and with a large enough wheel you could pump pretty much all you are likely ever to need and at as high pressure required for anything other than the grandest scale projects.