River Roller! Pontoon Boat that Rolls Across the Water!

[Matthew Lee Towne]

Ok, the fact that he didn't sink is a great success for me! Many in this forum are convinced that it would sink to the bottom of the lake. At the same time it does prove the point that improper traction will result in the craft becoming less buoyant. Most of the analysis here boils down to my design going from 0 to plane. At this point I see it as either being instantaneous or a slow process involving varying speeds of the trantoons.

Here is a link to the nearest I can find on YT, a truck with a giant v8 motor, plenty of tyres although it floats with the tyres about 50% immersed. When that lovely sounding engine is revved it goes - absolutely nowhere. I think the only question is, would it be better if more tyre (trantoon) flotation were available. My guess is yes, but not enough.

edit: I bet the builder was more than disappointed.

 

[Matthew Lee Towne]

Thank you PAR. The truck is a land vehicle that will also travel on water and does so poorly. I expect the River Roller to be a water vehicle that travels on waterwell and travels on land poorly. I am learning allot here. I hope, and expect, you will also learn something.

If you watch the video of the monster truck with the 4 big tires it should show you exactly why this won't work. I'm pretty sure that the guy that built it envisioned the same thing you do that when he poured on the power that it would climb up on top of the water and go but just the opposite happens while it moves through the water slowly as long as the RPM's are kept low as soon as he applies the power it aerates the water and sinks. The problem with using paddle wheels is they work pretty good at low speeds with a well designed displacement hull and the bigger the diameter the better but I doubt that you could make a boat plane with them even if it had a good planing hull but they were never intended to do this. They could be built from wood in remote locations and with steam engines no gearing or complicated drive system was needed just a simple connecting rod and for reverse you just reversed the rotation of the steam engine. I hope you go ahead with building the model you will learn a lot from the experience.

 

[Matthew Lee Towne]

Thanx Dave! The scale it 1:12. Though I was surprised to see my buoyancy calculations to be much more than that. Ie a 1:12 scale model would result in 1:100 buoyancy force. Does this sound right?

I'm glad to see you are proceeding with an actual model. What scale will it be? No matter what the results are it will definitely be interesting. Good Luck I hope you prove us all wrong.

 

[Matthew Lee Towne]

I understand the most efficient application of a paddlewheel. If I didn't before. You have all made it clear here. The question I have is can anybody see how inefficient a common displacement hull is? So if you replace a common displacement hull and propeller with this system, isn't there a chance that it might be more efficient? You know my answer. Correct me if I'm wrong, but I don't think anybody on this forum had addressed this question directly.

I understand physics. But once again this hasn't been done. We will see whose physics apply.

The builder could have saved a lot of embarrassment, grief and money if he had done a little study of basic physics.

It has 8 large balloon tires and if it had 16, it would go some better and with 32 tires, better yet. See where this is going Matthew? I have driven a large paddle wheel riverboat and if you look at any of them, you will see that they work best when the immersion just covers the blades in the vertical position. You might fool a lot of people Mathew, but fooling mother nature is another game altogether.

 

[Matthew Lee Towne]

PAR! You keep flip flopping between positive and negative! If you are correct, and the application of full power to all trantoons results in the River Roller becoming a submarine the solution is simple. Apply minimal RPMs to the interior trantoons. This will maintain buoyancy while accumulating speed to get on plane. This took me about five minutes to come up with after waterwitches video. Me, a complete novice on boat design. The question it begs is, why can't all of you positive people do the same?

I haven't contributed to this thread in a while, but as I previously mentioned and the video demonstrates, the wheels aerate a hole, and she squats, into the now much lower pressure area below the wheels. You can live in denial of physics, but you'd be wise to be within swimming distance of shore if you do.

 

[Matthew Lee Towne]

Ok. So does this answer the question of whether it can get on plane? Let's say yes. So if I can get on plane, what then? The whole hull will be working to move this vessel forward. There has to be some potential just in that. Speed? Control? Both? Dare I say efficiency?

Yes, you can make a paddle powered boat plane off. It's been done and a few have actually been fast, if wet and noisy. The paddles were of conventional configuration (aft) and driven very fast, with slight emersion. The last one I saw was a large jon boat (maybe 24') fitted with a small block and a single 5' diameter paddle, mounted on a rack off the transom. The large flat bottom helped control squat and it ran over 40 MPH. Of course had it been equipped with the same HP in an outboard, it would have likely been faster, certainly less wet and considerably lighter too. He had 1,000 pounds of SBC and drive attached to the paddle, which is a lot more than a Black Max hanging on the transom.

 

[Matthew Lee Towne]

I think that this is clearly proof of concept that this can get on plane by applying enough power to the aft Trantoon. So what if you combine that with interior Trantoons that are traveling at water speed and a front trantoons that are also pulling it forward. Just one scenario where it can work.

 

[Matthew Lee Towne]

Contraption!!!? Really!? So you aren't taking a stand on whether this will work or not? I was sure your original post was that it wouldn't. Come on, get on the River Roller, get off the River Roller, or get run over by the River Roller!

Thank you for that. Makes my day to be so recognized. Actually the definition of "works" needs lots of examination to determine if anything like your proposal is a significant advance in technology. Plenty of past similar contraptions have been able to float and make advance across the water. The best to my knowledge are those that use longitudinal tubular pontoons with screw threads wrapped about them fore and aft. Worked pretty well in bogs (and snow) compared to non floating vehicles.

You will have a very difficult time proving me wrong since all of my post is simply a challenge for you to prove your claims. As always, the challenge is to put up or shut up. Its always great to see something that no one has ever been able to achieve actually work. Do that and most of us here will be appreciative fans. The Wright brothers managed that but they worked from a basis of real science, study and progressive experimentation.

 

[Matthew Lee Towne]

Sorry but I have one more comment here. Embarassment? Is that how you approach things? With the fear that you will be emabarassed? Living in fear is embarrasing. There will be no embarassment or grief here. Only fun and the acquisition of knowledge. Hopefully for the both of us.

The builder could have saved a lot of embarrassment, grief and money if he had done a little study of basic physics.

It has 8 large balloon tires and if it had 16, it would go some better and with 32 tires, better yet. See where this is going Matthew? I have driven a large paddle wheel riverboat and if you look at any of them, you will see that they work best when the immersion just covers the blades in the vertical position. You might fool a lot of people Mathew, but fooling mother nature is another game altogether.

 

[Kailani]

I understand the most efficient application of a paddlewheel. If I didn't before. You have all made it clear here. The question I have is can anybody see how inefficient a common displacement hull is? So if you replace a common displacement hull and propeller with this system, isn't there a chance that it might be more efficient? You know my answer. Correct me if I'm wrong, but I don't think anybody on this forum had addressed this question directly.

I understand physics. But once again this hasn't been done. We will see whose physics apply.

A displacement hull can move tons of cargo at slow to moderate speed with very little horsepower. Then do you count complexity (cost and maintenance) and space used by the mechanisms ... ?

 

[Kailani]

Sorry but I have one more comment here. Embarassment? Is that how you approach things? With the fear that you will be emabarassed? Living in fear is embarrasing. There will be no embarassment or grief here. Only fun and the acquisition of knowledge. Hopefully for the both of us.

You have a good sense of humor and aren't afraid to fail. Build an RC model. You can probably do it for less than other people spend on things that don't even make a memory Seriously, build an RC model and see if you can make it work.

 

[latestarter]

Thanx Dave! The scale it 1:12. Though I was surprised to see my buoyancy calculations to be much more than that. Ie a 1:12 scale model would result in 1:100 buoyancy force. Does this sound right?

No it does not; buoyancy is based on volume so the ratio is 12 x 12 x 12 = 1728.
I am contrarian by nature and would like this to work and my first reaction was, why not.
The obvious thought seeing a wheel or roller is of it moving over land.
This machine is not rolling, in effect you are dragging cylinders through the water, the fact that they are rotating and providing some propulsion does not change that.
I agree with Kailani, keep going with a model you should learn a lot.

 

[PAR]

A displacement hull form is the most efficient, contrary to your assessment, given the Froude numbers in which it's expected to operate within. The propulsion system or type has very little bearing on the effectiveness or efficiency of the the hull form. The essential problem you have, is attempting to combine the hull volume within the drive system, which is fine in concept, except the 'toons are extremely inefficient as hull forms, resistance is huge and the shapes they make (what the water sees) is very poor for decreasing or limiting the various forms of drag they'll generate. This drag must be overcome, before you can achieve the Fr targets you might expect. Think of this as driving a car over a very washboard like dirt road. You can't get up to much speed as the wheels bounce over the ruts, because they're losing traction each time they grab and skip over the bumps. Spin them fast and it's just a bumpy ride, with limited ability to improve speed. Spin them slow and the ride is easier, but you still grab and release with its application over each bump. The same is true in the water, as the 'toons attempt to climb over the preceding 'toon's wave train, each one is chewing on progressively more aerated flow, that also is climbing up the following 'toons faces, which generates more resistance that must be overcome. It's a dog chassing it's tail thing and you just can't beat this, in the present vision of hull form/drive system.

I'm not here to agree or disagree with your concept. I find it silly out of hand for many reasons. I have no intrest in "getting on board" with your concept as (again) it's flawed in many aspects. It might make a worthwhile thesis, if appropriately conjectured, but hardly worth the bother, given what is currently understood, about the dynamics of the processes involved. As a mental or engineering exercise, possibly entertaining, but little more, in terms of practicality and efficiency.

 

[tom28571]

Sorry but I have one more comment here. Embarassment? Is that how you approach things? With the fear that you will be emabarassed? Living in fear is embarrasing. There will be no embarassment or grief here. Only fun and the acquisition of knowledge. Hopefully for the both of us.

Mr Towne, Please excuse any comments I might have made that angered you so. Continue with the search for new ideas even if this does not appear to be one of them..

 

[DCockey]

There is an very important difference between Mr Towne's "Trantoons" and conventional paddlewheels which result in a fundamental difference with how the water and paddles interact. Mr Towne's Trantoons have the paddles mounted to a cylinder. Water cannot pass through this cylinder which means there can be little radial flow of water along the paddles, and no radial flow at the intersection of the paddles and cylinder.

Conventional paddlewheels have the paddles mounted to an open framework. An example are the paddlewheels on the high speed craft as shown in

As a result of the paddles being mounted on an open framework water can flow radially along the paddles. With the paddlewheel moving forward water along a paddle will flow inward in the initial phase of the paddle passing through the water, and then the flow will reverse and flow outward during the latter phase of the paddle moving through the water. This difference will have major implications of the efficiency of a conventional paddlewheel with an open framework vs the Trantoon with a cylinder.