Anybody in here mess with getting better FE out of Boats?

[Hersbird]

Originally Posted by hayden55

Can anybody explain how to use that calc for a 15' flat bottom? lol

Use the planing hull and you need the weight, it should be pretty close. A flat bottom with enough power is the most planing hull there is, the v-hulls plane but are designed to keep a cut in the water for stability on waves and turning. A semi-displacement hull is the most inefficient trying to do both a smooth ride and good speed, think James Bond yachts. Who cares how much gas costs because money is no object. There are some exceptions but speed is always a consideration. They will make claims like most efficient design over 15 knots. Displacement hull are traditional ships and sailboats. They are the most efficient hulls speed not a factor. Yet with enough length they can also be pretty fast. The French built a 434 ft long destroyer that ran 52 mph. I would love to have seen that flank speed, boilers at battleshort pressures, blow by.

[Andrey]

Originally Posted by Daschicken

I was actually reading up on this subject earlier, and chances are boat efficiency is very closely related to airplane efficiency. One big thing I found is that jet drives are not as efficient as props. Just like planes, you will gain efficiency from large diameter 2 blade props, more blades=more turbulence.

No idea on hull design and water interference yet, haven’t looked into that enough.




That is really disappointing. I believe the BF60 engine is closely based on the 1st gen insight engine, and comes with lean burn.

If you do a little research, you'll find out that 8mpg is really good for a boat. Although my boat is lighter than that Insight that you're somehow comparing it to, the drag and single speed make this an apples to freesbees comparison.

[teoman]

Try using a kite to pull the boat.

[cRiPpLe_rOoStEr]

Originally Posted by JSH

I would say this closer to the ecomodder solution:

That's quite common in Amazon.

[freebeard]

In Vietnam they stick the long tail down a pipe and use it to pump water in the rice paddies. In Thailand they race.

https://duckduckgo.com/?q=long+tail+...deos&ia=videos

[cRiPpLe_rOoStEr]

Originally Posted by freebeard

IIn Thailand they race.

What does surprise me about the usage of those long-tails in Thailand is they fit it to nearly every Diesel engine regardless of size.

[hayden55]

They use them here as well. Well, we call them mud motors. Basically makes it to where the boat can go anywhere hunting wise. The Game and Fish comission about bans them every single year so not something I wanna sink money into and then not be allowed on WMA land. Mostly, they are noisy and everyone hates them.

[cRiPpLe_rOoStEr]

Originally Posted by hayden55

They use them here as well. Well, we call them mud motors. Basically makes it to where the boat can go anywhere hunting wise.

In Amazon they're used for general transportation. Even in big cities such as Manaus we see a lot of them in the "voadeiras". It's used there to prevent the propeller to get stuck on tree stubs below the water while crossing an igapó.

Mostly, they are noisy and everyone hates them.

Well, soundproofing is not really a top-tier priority on those, but honestly it didn't bother me too much.

[freebeard]

I think the most interesting use is to make one an Archimedes screw (sorta), to pump water out of rice paddies.

[dremd]

The boat I use most often gets about 150 MPGe on 8 210 amp hour 6 volt golf cart batteries 3 phase permanent magnet dc motor with 2 belts driving a prop shaft out the keel.
Cruise speed is 5 mph Flank speed is 6 mph, realistic range is 70 miles. It’s a 1982 Duffy electric packet.

Edit: here we are on our local river. https://youtu.be/rm2FhL8X4yU