pump piston powered boat

Liam, where are you up to on the build for the boat itself?

I have a prop driven pedal boat, converted from a Dart 18 catamaran, and I don't live very far away from you if I can be of any help. Here's a video of the boat:

https://youtu.be/ClD56HlZj00

 

As a diagram it is correct. The design, as drawn, is very inefficient. There will be a lot of friction and turbulence. I have a basic understanding of it, but it is a specialized branch of engineering. For a more constant thrust, an impeller would be better. However, try to measure your muscle output for an hour or so. Any elliptical or bicycle exercise machine will give you watts produced.

 

Thank you Gonzo I'll let you nknopw how things develop best wishes

Liam

 

Thank you Tiny Turnip, I really like your pedal boat. We haven't started to build the boat yet but I'll let you know when we begin you would be very welcome to come and advise I live in Fallowfield Manchester best wishes

Liam

 

It might be better to let the outlet go to atmosphere for more thrust

 

If you haven't started to build, then if you have an interest in the performance of the boat, the single thing aside from the method of propulsion that will improve the achievable speed most is making the boat longer.

It would be very simple and quick to make a 4.8m long squareish section hull skinny hull with outriggers for stability, from 2 sheets of 6mm ply and some sundry other bits and pieces that would give you ample buoyancy for one person.

If you're not worried about the speed, then please disregard this.

 

At the risk of coming across as a negative Nellie I doubt that what you propose will move the boat at all. I have a hand pump of similar piston dimensions that I use to pump up my RIB, a simple test with something like this could help determine if your idea is viable.