View Full Version : paddlewheel


rasorinc
12-13-2008, 01:16 PM
Is there such a thing as a more efficient paddlewheel? How about shape--rather than a flat wood board? spoon shape?? cupped shape?? thanks much.
Forgot, this will be a small application about 22".

Guest625101138
12-13-2008, 06:48 PM
Is there such a thing as a more efficient paddlewheel? How about shape--rather than a flat wood board? spoon shape?? cupped shape?? thanks much.
Forgot, this will be a small application about 22".

Think BIG. You need large diameter and wide wheel/s. THe objective is to have very low slip and this requires large blade area. However shallow immersion is more efficient than deep immersion.

Think small with the arc of immersion. Less than 60 degrees is what I recommend for efficient operation.

If you get the basics right then blade shape or blade articulation does not matter much. I would recommend a slight lead with the blades so they produce a net uplift rather than down force. The blades should exit the water cleanly without lifting any noticeable volume.

The best size wheels will have some windage issues that you can be reduced by fairing around the wheel/s.

I have posted performance predictor elsewhere but it needs to be adjusted to suit the boat. You can play with the size of the wheels to determine the power required for various combination of diameter and width.

Rick W.

rasorinc
12-14-2008, 11:38 AM
Rick, thank you for your reply. I drew out a 20" circle and divided it into 60 degree radiuse's and came out with 6 paddles. Reducing to 52 degrees + or -
I could get 7 paddles. Question-- if the paddles were, say, 18" x 6" out of steel and mounted on a steel ring all very strong could they turn at 3,500 RPM? And if so, could power and speed be an expected outcome?
Thanks very much, and I know I'm over my head on this. Stan

messabout
12-14-2008, 01:47 PM
I'm over my head on this subject too. However I suspect that a paddle wheel turning at 3500 or anywhere near that speed, the result will be a lot of splashy foam and very little propulsion. Balance, too, will become problematic.

Examination of the geometry of the wheel and its interface with the water, easily leads us to the conclusion that bigger is better. Lay out a path tracing of a single blade as it moves through the water. You will see that there is much down force and subsequent up force generated. All that is useless expenditure of energy. The force that you want to generate is in the horizontal plane. A big wheel is far more efficient in that regard, and a giant sized wheel is even more efficient.

A wheel in the size that you are contemplating is better suited for mixing daquiris or margaritas for a large party.

Guest625101138
12-14-2008, 03:22 PM
Rick, thank you for your reply. I drew out a 20" circle and divided it into 60 degree radiuse's and came out with 6 paddles. Reducing to 52 degrees + or -
I could get 7 paddles. Question-- if the paddles were, say, 18" x 6" out of steel and mounted on a steel ring all very strong could they turn at 3,500 RPM? And if so, could power and speed be an expected outcome?
Thanks very much, and I know I'm over my head on this. Stan

You need 12 paddles because you want to have at least ONE always in the water. With 6 combined with 60 degrees of immersion you will have a brief period with no paddle in the water.

The speed of the wheel will depend on the speed of the boat. My initial impression was that you were making a 20" scale model boat. I did not relate the 20" to the size of the wheel. For a full size boat 20" is hopelessly small if you seek efficiency.

The efficiency is primarily related to the slip of the paddles. The peripheral speed would ideally be 10% faster than the boat speed meaning the paddlewheel would be a bit less than 90% efficient. This usually results in a massive wheel relative to the boat. A wheel of practical proportions can usually give better than 75%.

If you were to spin a 20" wheel at 3500rpm it would be an excellent fountain but not much value in driving a boat.

If you provide some detail on the type of boat and target speed I will give you the wheel size required to get around 75% efficiency. I expect you will be surprised by how big it needs to be.

Rick W

rasorinc
12-14-2008, 03:37 PM
Thanks very much for the input and your knowledge. I thought I might be chasing a wild hare and you just proved it. It might make a big blender.....
I'll drop my idea now. Thanks again, Stan

tom28571
12-14-2008, 05:57 PM
Rick,

You seem to know a lot about paddlewheels. Have there been any successful articulated paddles that had only vertical paddles? How about tip fences on the edges of paddles? I've spent a number of hours watching paddlewheels thrash through the water on a riverboat and wondered about these things.

Guest625101138
12-14-2008, 06:29 PM
Tom
I have not built a wheel but have looked at design information and validated it against various examples I have found and some basic test information from human powered wheels.

If the wheels are sized correctly and positioned properly then things like blade shape and articulation have less benefit.

There are certainly articulated paddles in operation and they are regarded as successful.

THere is an array of paddlewheels shown in this video clip:
http://www.youtube.com/watch?v=-QjRM-cQpHw
If you look carefully you will see many examples and get an idea of the different performance. Even the best of the paddlewheelers has under sized wheels in my view. However it still performs well against the competition but I doubt that many of the boats have well engineered props. A good canoe could do 7km in about 35 minutes so none of these boats are very impressive.

Look through the video a few times and pick out all the wheels. It is interesting to watch Hydrodynamosaurus at the start. You will see it kicks up a lot of water until it gathers speed and as the slip reduces there is less wasted power. A bigger wheel would cause even less spray. Also notice that the paddlewheel gives the best acceleration.

Rick W

boat fan
12-14-2008, 09:28 PM
I really enjoyed watching that .

So Rick , in terms of total overall efficiency , how does a paddle wheeler compare with a conventional shaft / prop setup , in a power boat assuming both systems were configured optimal. Also assuming the same boat of course .By efficiency I primarily mean fuel consumption , power input , for a given arbitrary speed .

Guest625101138
12-14-2008, 09:42 PM
So Rick , in terms of total overall efficiency , how does a paddle wheeler compare with a conventional shaft / prop setup , assuming both systems were configured optimal. Also assuming same boat of course .By efficiency I primarily mean fuel consumption , power input , for a given arbitrary speed .

Peak efficiency for either prop or paddlewheel is up around 90%. Realistically after allowing for windage of wheels or appendage drag on a prop they both end up more like 80%.

Problem with paddlewheels is that they do not suit rough water applications.

Problem with propeller is that it is not suited to shallow water or obstacle ridden water at least for efficient configuration.

So the selection is really application specific. With good design either system can achieve high efficiency.

Rick W

boat fan
12-15-2008, 12:32 AM
Thank you Rick.

80 % .....Quite impressive :)

tom28571
12-15-2008, 07:19 PM
Thanks Rick, a very interesting video.

I do know that the maintenance on the paddlewheels was way beyond any propeller boat I have ever experienced. Having driven both, I find it difficult to believe that a paddlewheel can be as efficient as a propeller. A propeller can operate at its max efficiency all 360 degrees of rotation while a paddle wheel blade only reaches max thrust at one point, dead bottom center. The rest of the time it is immersed, it is fighting gravity and using energy to do it. A simple view, I'm sure, but it seems reasonable.

Guest625101138
12-15-2008, 08:15 PM
Thanks Rick, a very interesting video.

I do know that the maintenance on the paddlewheels was way beyond any propeller boat I have ever experienced. Having driven both, I find it difficult to believe that a paddlewheel can be as efficient as a propeller. A propeller can operate at its max efficiency all 360 degrees of rotation while a paddle wheel blade only reaches max thrust at one point, dead bottom center. The rest of the time it is immersed, it is fighting gravity and using energy to do it. A simple view, I'm sure, but it seems reasonable.

The main point of the video was to show that a well designed paddlewheel will be as efficient as a prop. Hydrodynamosaurus has bettered many propeller driven boats.

If the water is only 1ft deep you can get much more efficient operation with a large diameter, full width wheel on a moderate size river boat than having a small exposed prop or jet thruster working at very high velocity ratios. Also the first log that comes along will destroy the prop or decent chunck of weed will foul the jet inlet.

Most current paddlewheels are sized for times of abundant fossil fuel so efficiency has not been a design priority.

Rick W

Ramius41
12-16-2008, 11:18 AM
I'm not sure if this video has been posted before. But it shows a rather fast paddlewheeler!

http://www.youtube.com/watch?v=02DKzQFsgJU

http://www.youtube.com/watch?v=meDcNK0-tio

Stumble
12-16-2008, 07:53 PM
Just curious what if any andvantage a tread instead of a wheel might be? Think something like a tank tread... I can see it would allow a lot more horisontle force to be applied with relatively low vertical force.

Guest625101138
12-16-2008, 08:17 PM
The fastest ones use treads so the efficiency is better than wheels. Here is a good comparison:
http://www.youtube.com/watch?v=tccrBWtSda4

The amount of spray is indicative of wasted power. You can draw your own conclusion.

Rick W

FAST FRED
12-17-2008, 06:35 AM
Just curious what if any advantage a tread instead of a wheel might be? Think something like a tank tread.

Works in reverse even better.
I had a friend that took 100ft of fire hose and installed wood hinged flaps by sewing them on.

He took a front spindle from a car and mounted it with a wheel (no tire) on the stern of his anchored boat .

With the belt as an endless loop dropped into a 2K -3 K tidal flow he was able to power a small alt by having it run a rubber wheel ( solid from shopping cart.against the rim of the car wheel.

It worked like the old generators we had on bicycles as a kid , but it created enough energy to keep a small cooler cold.

Left unattended it still worked , except when a fish guy would chop it into his prop be passing too close astern.

This of course was to remove energy from the water , not put it into the water as a paddlewheel would ,

but it kept the BEER COLD!!

FF

woodchuck
12-25-2008, 09:29 PM
The Oh! Susana, a 78 foot stern wheeler with a stainless steel hull used a gallon an hour of diesel at 8 knots. I didn't believe the gauge and stuck the tank everyday. The wheel has less slippage than a prop and has a lot more surface pushing the water.
There is a lot more maintanence as there is a lot of strain and hammering on the buckets. They slam the water hard ever cycle and then unload. Checking the bolts in the buckets was a daily job and we frequently found missing bolts even with self locking stainless bolts. I would use lock tite if it were mine.
The boat had no vibration, not even rings on the surface of my coffee on the dash. Pans on the stove or dishes on the table did not move. I haven't found that to be the case with displacement hulls with props.
The drive chain is a constant nightmare in salt water. We tried everything we could find and plain old grease liberally applied every evening was the best but had to be done everyday. STP, chain lube, lith were all tried but were poor.

FAST FRED
12-29-2008, 06:14 AM
plain old grease liberally

Have you tried synthetic wheel bearing grease?
It sheds water , and is cheap to try.

FF

woodchuck
12-29-2008, 07:37 AM
Sure did but wasn't any better. The constant spray was just too much for any thing to last at all. Motorcycle chain lube is very sticky but didn't work long either. Maintaining the chain was just a daily chore that had to be done like a lot of things on a large boat. It was worth it for the fuel savings and the looks it got. Not many real paddle wheel boats out there.

tom28571
12-29-2008, 06:57 PM
Sure did but wasn't any better. The constant spray was just too much for any thing to last at all. Motorcycle chain lube is very sticky but didn't work long either. Maintaining the chain was just a daily chore that had to be done like a lot of things on a large boat. It was worth it for the fuel savings and the looks it got. Not many real paddle wheel boats out there.

Do you have trouble with broken link pins? That was the major issue and grease was smeared by the handfull on the chains. Having a chain break due to a broken pin slipping completely out was a constant fear. Inspection every 30 minutes was the order of the day. Replacing broken pins on those big chains is a dirty job.

woodchuck
12-29-2008, 07:22 PM
No pin problems but we greased every day. We had problems with the bucket bolts coming out. Whe wheel was stainless so didn't corrode but it did get stress cracks which we welded since we had a welder in the engine room. The owner was a tool and die man so we had a mini machine shop on board.
He designed the power steering using the parts from a Ford F-450. It was great Very light and positive feel. Did find out it needed a huge resevoir because when the engine was off all of the fluid returnd and the stock can was't big enough. Nothing like a few quarts of power steering fluid on the deck to make things interesting.
I believe the wheel sprocket was from a cement mixer and had a huge chain. There was a marine transmission chained to a reduction box that was chained to the wheel. Only the outside chain was a problem.
On smaller chains there are several grades of chain. I have seen motorcycles destroyed because the owner bought ag chains for much less than ones designed for bikes. A ten horsepower chain on a 1000cc bike is going to break quickly and usually jam betewwn the sidecase and the sprocket, tearing a hole.
Buy the best chain you can that is rated for the job. Size alone is not the only important thing.
The chain had been from Ohio to south Texas and back to ohio with out replacement so I guess the grease problem wasn't as bad as I thought. It was just an aggravation to walk the chain around and brush on grease every day, particularly since I always seem to wear some when finished.

Guest625101138
12-31-2008, 04:35 PM
The Oh! Susana, a 78 foot stern wheeler with a stainless steel hull used a gallon an hour of diesel at 8 knots. I didn't believe the gauge and stuck the tank everyday. The wheel has less slippage than a prop and has a lot more surface pushing the water.
........

Woodchuck
Thank you for the information.

I would like to see a photo of the Oh! Susana if you have one. Also more technical information on the engine and size of the wheel.

Rick W

woodchuck
12-31-2008, 05:30 PM
Lost the first reply so will try again.
I am in Matagorda, Tx in an RV so have no pictures with me. Send me an address and I will get it to the former owner who will probably answer you. He was very proud of the boat.
Things I know about it.
3/8 stainless hull
10X10 Wheel
composite buckets (seem to cause problems
and were replaced with wood)
4-51 Detroit
5 waterproof bulkheads
Drew less than 18 inches of water
handled like a log at slow speed
House like interior which ws poor. The owner bought
it that way and just never changed it.
Layed out like an apartment not a boat or RV
Hard to dock in conventional way since wheelhouse
could not see rails.
White trimmed in red with red smoke stacks (fake)
attention getter
I understand it was insured for $500,000, sold for
less.
Joe is 86 but very active so I imagine he will answer you
Chuck
Greenwoodchuck2@aol.com

Guest625101138
12-31-2008, 06:26 PM
Chuck
I have sent email that you or Joe can reply to.

Rick W

woodchuck
01-01-2009, 09:13 PM
paddlewheels are more complicated than they first appear.
They are most efficient when the bucket is flat. A cupped bucket would carry water up and end any advantage they got on the way under. The buckets are most efficient when barely submerged. Water over the top puts drag on the way air in a vaccum behind a car does. The boats are difficult to balance since the bow climbs a noticeable amount. The old boats just loaded for it. Pleasure paddlewheelers today put weight in the bow hold and live with it. It isn't that important if not hauling freight for a profit.
The old steam boats had huge steam engines and used rather cheap fuel so they could overcome any flaws with brute force. Horsepower available from steam is awsome and the engines are mostly very low tech with little precision machine work. I wonder why no one is building any today. Scrap material to burn is very available. I guess it is just too much bother to wait to start and watch pressures.

tinhorn
01-02-2009, 01:57 AM
You can download a free PDF of a bunch of ancient paddlewheel specs, data, and formulas here: http://www.lulu.com/content/1948578 .

woodchuck
01-02-2009, 09:14 AM
Good stuff. The net actually contains a huge amount on paddlewheelers considering how few there actually are today. I wonder if it would be economical to build steam powered wheels today? I understand a prop is better above 300 horsepower but don't know why. It may have to do with size or tech available in the past.

tinhorn
01-02-2009, 11:55 AM
Well, grasping new technologies is what we humans do. I was disappointed in the amount of readily available paddlewheel info I was able to find when I was searching. Fortunately, I had a lot of time on my hands when I assembled that collection.

Judging by feedback in another thread here (which I've lost track of since I've been absent for awhile) paddlewheels are excellent devices in certain applications.

ancient kayaker
01-27-2009, 03:27 PM
I didn't realize chains had been used for driving paddles; sounds like a recipe for high maintenance.

I have memories as a child being in the engineroom of a sidewheeler watching the huge steam engines effortlessly pushing the massive cranks. .Much later on a sternwheeler I watched the pair of big pushrods drive the wheel.

More recently I was on another sternwheeler and went back to watch the action; nothing. The damn wheel was a fake, rotating courtesy of the wash from the diesel driven prop! And they call it progress!

Maybe I'll build a steam paddlewheel drive for my kayak.

woodchuck
01-27-2009, 06:57 PM
Chains do require looking after as do pitman arms or anything else around water or salt water.
I was frequently asked what drove us. Most people thought the wheel was for decoration. A number of them are just fakes on tour boats.
Sure would load a kayak but I saw an ad a few years ago for a kit to put a wheel on a jon boat and use a B and S motor. In stumps or shallows it would work great.
There was also an article about a Yukon Delta house boat with a wheel added.

drmiller100
02-12-2009, 12:29 AM
are there many planing paddlewheels?
I was thinking it would be fun to put a paddle wheel into a jon boat.

i did hunt down a guy who had this video.
http://www.youtube.com/watch?v=JGdkHIMbHYM

he claimed you could ride around the lake and steer by leaning.

Guest625101138
02-12-2009, 01:29 AM
http://www.youtube.com/watch?v=meDcNK0-tio&feature=related
http://www.youtube.com/watch?v=tccrBWtSda4
http://www.youtube.com/watch?v=eaGLNcIkSm0
http://www.youtube.com/user/fasttrackdriver

drmiller100
02-12-2009, 02:23 AM
I would think the paddle tire guy would be faster if he turned his tires around so they "lifted" rather then "dug".

The worst thing you can do is throw water straight up in the air, as that provides downward thrust and lost work.
Lifting at the front of the tire isn't all bad. The worst thing that will happen is you climb up on top of the water and lose "traction."

I've done a fair amount of work with deep powder snow and snowmobiles, and the whole goal is to get up on "plane". You do this with lift as much as "thrust."

:) :) :)

volkswagen50
04-25-2009, 07:10 PM
I can answer the question about why there are no steam powered ones easy enough. In the US, coast guard regulations required the engineer of the steamer to have 4 years of full time apprenticeship to run a steam powered boat. The Ticonderoga of lake Champlain ran into this issue in 1953, when all the engineers were in their 80's and new guys just couldn't get the needed experience. This is how the Ti ended up at the Shelburne museum.

The Ti used 2 tons of coal per hour at max speed. To use wood you need almost twice the amount. The best wood has 17m BTU per ton, coal has 26m BTU for its best type. the worst coal has 16.2M btu. Plus coal requires less handling.

It was a sidewheeler, but I still feel it relavent info. The Ti had paddles that changed angle as the went into and exited the water. i can't remember the name of the system, but it was commn in the mid 1800's on up to the end of commercial wheelers.

Thanks for all the info guys! I've always liked paddle wheel boats, so this is a good thread to learn some practicle info with.

Michael Lawton
03-01-2010, 02:40 PM
My slant exactly,
Consider a snowmobile,
I was trying to apply prop calculations to the problem
I was hoping someone could give a cookbook approach for me.

MeadMan
04-25-2010, 02:10 PM
Snowmobiles crossing water:
http://www.youtube.com/watch?v=OdjI9s7cotI

Motorcycle crossing water:
http://www.youtube.com/watch?v=paGZ07nvIxk&feature=related

Jeep (if you want to call it that) crossing water:
http://www.youtube.com/watch?v=mjLH89uXYmM&feature=PlayList&p=9958AA7DD7271291&playnext_from=PL&playnext=1&index=33

Whenever I've considered paddlewheels, it's always been in the context of speed and performance boats. I'm a novice and I'm here because I love this stuff.

The faster the boat travels the more it's on-top of the water. It seems there is planing with minimal displacement, but it seems there's high-speed skimming, which is planing with very minimal displacement. It seems that as you approach speeds of say 100 mph +, a wheel rolling on the water would achieve be the best in terms of minimal drag.

A surface-propeller on a high-speed boat is really a wheel screwing across the water. It seems in efficient, but really what's so inefficient about it?

I love reading the discussions at this forum. Thanks to all for sharing your interest, knowledge and experiences.

ssphb1
08-30-2010, 05:24 PM
Paddle Wheel Revive

Hello, I am new here but have done much reading recently.
I am posting in this apparent abandoned thread hoping to revive.
In my opinion, most of the information in this thread is incorrect:
Paddlewheel design, spacing, etc…

I have read some good information on paddlewheels in other thread and I hope to develop a positive dialogue and to share what I believe will revive paddlewheels.

I have a U.S. patent on automation of paddlewheel trimming which solves many problems with paddlewheels.

I have built many small paddlewheels, all worked well, my perspective is the search for efficiency, is why I stated incorrect information above. There are no rules to making paddlewheels; it is what you are looking for. My technology works with all paddlewheels for propulsion.

For an overview of my technology, and my current project:
www.PowOarsMarine.com

Please note technology in the pages is proprietary and so u must ask to use them in the U.S.

Hope you enjoy.

Peter

goodwilltoall
09-04-2010, 11:15 AM
Interesting.

Peace.

PAR
09-04-2010, 03:27 PM
It never ceases to amaze me that folks will attempt to "re-invent" things that have long since been superseded by evolving technologies.

If you'd like to look into smoothing out the inefficiencies of paddle wheel drives, it might be best to look at the efficiencies of props (in their various configurations). This will give you an idea what you'll have to do battle with in regard to efficiency.

For what it's worth, you're not the first to think this, though you will be the first to prove everyone else's conclusions incorrect. Good luck with that.

ssphb1
09-05-2010, 05:13 PM
"re-invent things" i have reinvented nothing, rather introduced a system for deployment of paddle wheels that solves the majority of paddle wheel problems of the past. why, in an effort to find efficiency, which is not provided from screws.:P

"inefficiencies of paddle wheels" is this personal knowledge or where do you derive this position from, or is this just an opinion? :?:

Paddle wheels are one of the oldest machines on this planet, thousands of years old, k+ for propulsion, because they work, and are easy to build.

Screws where adapted, because they better fit the the evolution of steam power etc. faster rpm = more power. and we cant forget our ever waring society.

However they days of cheap fuel (energy) are over.

Do you (PAR) think you could build a 20' pontoon (enclosed patio) boat with 2500 lbs displacement that cruses at 4 knots at 60 watts total input, <1/10 hp, with a screw prop?
my first boat (when adapted with a PW) never consumed over 110 watts, acceleration was basically immediate (less the 3 seconds and then back down to the typical 60 watts), ease of control was superior to any vessel i had been on, my 6 year old daughter could drive and park it, well.

i actually reduced my motor capacity (changed the motors) from 1000 to 500 watt input and gained 7% to achieve the 60 watt average. both gear motors sets where rated at 86% in to out, so actually <50 watts to the prop!:cool:

with screws, (I tried a few), (the apparent problem was the implied surface area (friction) ratio to volume of water pumped.) i consumed 10-20 times the power to achieve similar speed, very poor control, uncontrollable in moderate winds.

Fortunately the batteries i had to buy for this failed attempt very well capacitate the boat when efficiency was found!:idea:

"everyone else's conclusions" :confused: I am amazed, how often apparent intelligent people speak in absolutes! I think this is why global intelligence has fallen 20 points in the last 40 years, or so i have read and come to this conclusion.
what happened to science, objective thinking, sorry rant.

hope all are having, had a great weekend.

PAR
09-05-2010, 06:53 PM
Ssphb1, you're absolutely right, I haven't a clue and please accept my attempt at a graceful bow out, as you're skills and understanding far exceed that of me, in spite of my two engineering degrees and marine history buff nature.

Naturally, being the history buff that I am, I probably shouldn't mention the two commercial hulls, that were built side by side then raced across the Atlantic, one a wheel drive, the other a screw, both using the same steam engine. The results would just piss you off if you're a wheel fan, but then of course they where using "your" wheels. Maybe you can improve the 2:1 thrashing the wheel drive took.

Windmaster
09-05-2010, 09:37 PM
The site www.PowOarsMarine.com although very interesting has so many embarrassing spelling mistakes. You should get someone to go through it and correct them all! "yatchs" for yachts etc!

troy2000
09-06-2010, 02:02 AM
"re-invent things" i have reinvented nothing, rather introduced a system for deployment of paddle wheels that solves the majority of paddle wheel problems of the past. why, in an effort to find efficiency, which is not provided from screws.:P

"inefficiencies of paddle wheels" is this personal knowledge or where do you derive this position from, or is this just an opinion? :?:

Paddle wheels are one of the oldest machines on this planet, thousands of years old, k+ for propulsion, because they work, and are easy to build.

Screws where adapted, because they better fit the the evolution of steam power etc. faster rpm = more power. and we cant forget our ever waring society.

However they days of cheap fuel (energy) are over.

Do you (PAR) think you could build a 20' pontoon (enclosed patio) boat with 2500 lbs displacement that cruses at 4 knots at 60 watts total input, <1/10 hp, with a screw prop?
my first boat (when adapted with a PW) never consumed over 110 watts, acceleration was basically immediate (less the 3 seconds and then back down to the typical 60 watts), ease of control was superior to any vessel i had been on, my 6 year old daughter could drive and park it, well.

i actually reduced my motor capacity (changed the motors) from 1000 to 500 watt input and gained 7% to achieve the 60 watt average. both gear motors sets where rated at 86% in to out, so actually <50 watts to the prop!:cool:

with screws, (I tried a few), (the apparent problem was the implied surface area (friction) ratio to volume of water pumped.) i consumed 10-20 times the power to achieve similar speed, very poor control, uncontrollable in moderate winds.

Fortunately the batteries i had to buy for this failed attempt very well capacitate the boat when efficiency was found!:idea:

"everyone else's conclusions" :confused: I am amazed, how often apparent intelligent people speak in absolutes! I think this is why global intelligence has fallen 20 points in the last 40 years, or so i have read and come to this conclusion.
what happened to science, objective thinking, sorry rant.

hope all are having, had a great weekend.

If you joined this forum hoping people will listen to what you have to say, you probably shouldn't have started by getting snotty with respected, long-standing members whose worth has been proven time after time. We have a surprising large number of experienced, knowledgable (and yes, educated) professionals contributing their time here.

If global intelligence has indeed fallen in the last few years, it's probably due to the proliferation of self-anointed internet experts drowning out science and facts with their arrogance and pseudo-knowledge....

ssphb1
09-06-2010, 02:03 AM
Windmaster, thanks for the critique, i have a disability with spelling, you are correct, i have done too much editing without a full review, this is my first web sight, but am learning. i appreciate the "!" and will get right on it.

PAR, there are very few absolutes i know, probably because of my (poor?) choice not to be educated to think within the box. i chose to work and create.

One of many reasons i chose to follow this was the MIT professor (the one who held the human powered boat races in the 80's) statement that after years of holding these competitions it appeared to him that a PW propelled hydrofoil would obviously be dominate, if some one could figure out how to do this, which i have.

it appears to me PAR you see no value in paddle wheels, so i am asking are you only here to be a neigh sayer? I've read a few of you posts, and i do see insight and sharing.

i am here to share my insights, and hoping to learn, grow. i did, do not mean to be insulting.

i am not a fan of PW i never actually saw one, that i recall, befor i built one. i am a fan of efficiency, PW are just the most promising propulsion i have found yet and so i tweeked it. and the have many many advantages over and above efficiency. i laughed as most do when they hear of it, untill they see it work.

it seams very odd to me though, that just because two similar ships with apples and oranges for propulsion seams like a fair test. but yes incorporating my tech would of helped, or why else did my floating turd perform so well.

ssphb1
09-06-2010, 03:06 AM
If you joined this forum hoping people will listen to what you have to say, you probably shouldn't have started by getting snotty with respected, long-standing members whose worth has been proven time after time. We have a surprising large number of experienced, knowledgable (and yes, educated) professionals contributing their time here.

If global intelligence has indeed fallen in the last few years, it's probably due to the proliferation of self-anointed internet experts drowning out science and facts with their arrogance and pseudo-knowledge....

i am here to share my insights, and hoping to learn, grow. i did, do not mean to be insulting. or snotty.

i apologize to all, i may have mistook his good will and misplaced emphasis in the writing.

global intelligence was out of place, off subject, frustration.

for reference, my boating knowledge is self taught, it is mealy a hobby that has become over grown. i am by no means an expert, the only reason i wrote my patent was to see if i could, to grow. i was amazed at the lack of prior art and i saw potential. my forte is in efficiency, layering of systems and time management.

PAR
09-06-2010, 03:19 PM
Two identical hulls have the same resistance to propulsion, the same frictional resistance, the same wave making resistance, the same parasitic resistance, so it goes to reason that having only the drive method difference would surely make a reasonable comparison.

Do you honestly think the paddle wheel builders walked away, happily embracing the screw? They tried everything and still got handed their businesses and concepts. This occurs frequently in industry. We don't see many biplanes around any more either, even though they are much more efficient and generate more lift which is the fundamental thing you'd desire from a good wing design. Yep a Fokker tri wing could easily out maneuver a FA-18, but the FA-18 would shred the tri-plane on it's first pass, making the extra maneuverability and higher efficiency numbers a bit of a moot point, particularly if you're the pilot.

You're not the first to try what you are attempting, but you've made assumsions that don't add up and more study on your part would relieve you of this burden.

BTW, screws where not adopted because they"fit the evolution of steam power". They were adopted because they didn't roll or pitch out underway in 30' swells on large vessels like wheels do. It doesn't matter how efficient the big wheel is, if it's not immersed and this was the crux of the problem for merchant vessel and wheels.

ssphb1
09-06-2010, 10:49 PM
thank you PAR

granted screws have distinct advantages, as do paddle wheels.

i see the greatest disadvantages of a screw is the direction of rotation and the angel or pitch of the screw from which the thrust is applied, so that thrust is not fully in line and also causing twist on vessel, (which is solved by counter rotating screws.)

further when submerged both the leading and pushing surfaces are producing friction. on surface piercing screws, the leading surfaces contact much less water because the water is positively displaced by the pushing surface = less friction allowing the pushing surface more power because of increased efficiency. however thrust is still not in line and there is the problem of splash (entry) and lift (exiting) caused by surface piercing.

where a properly designed PW, (be it simple, articulated paddles, or multi axle (endless line-belt)), passes the energy from the prop directly in the desired direction, and because it is a surface reactor there is very little drag from the leading surface because the water is displaced by the pushing surface.

because a PW have high traction and low relative speed (as do larger screws) splash is much easer to control (by design of the wheel(s) and/or paddles) and lift can be almost be eliminated while efficiency is increased by directing the lifting water to the desired direction with a trailing fin which is also highly effective in controlling trim by the lifting (or lack there of ) effect produced by directing the water.

splash and lift are much harder to control on surface piercing screws because of the inherent increased surface area caused by there pitch to produce the screw, centripetal reaction, and turning in the wrong direction.

your stance for the move away from PW is highly valid, my self trimming technology greatly reduces these disadvantages however. i have incorporated articulation for steering (nothing new), and automated trimming with consideration of the seas (controlling dig and allowing twist).

this was not easily possible in the past, but with modern materials and control is, can be very viable and reliable. it further enables great reduction in size and weight, while retaining simplicity and effect.

ssphb1
09-06-2010, 11:15 PM
You're not the first to try what you are attempting, but you've made assumsions that don't add up and more study on your part would relieve you of this burden.

No, I have read also, I understand that the conversion to screws was highly controversial and initially regected and then resisted. Much as my work is often put down, usually until people actually see it work.

I do not think that automated trimming of PW was practical in the day, and is why there was so little prior art on the subject, along with people gradually accepting being screwed (joke) and turning away from PW.

I strive not to assume, but... I beleive I have basicly explained my premises in my prior post.

You are correct it is a burden. Is why i am here. Direction is requested.

thanks.

tinhorn
09-09-2010, 11:52 AM
...along with people gradually accepting being screwed (joke) and turning away from PW.

Hahahahahahaha!

zebinuk
10-10-2011, 07:43 AM
Greetings from Brisbane river, Australia.
We have a number of grand paddle wheelers plying the waters here, however of all the house boats in the area none seem to have picked up on the romance of slap, slap , slap.
Being a novice in all things paddle wheel i was wondering how would one work out the size of drive (Diesel kw) required compared to wheel size and boat weight?

I am thinking of building a 15mtr house boat and paddle power appeals.:idea:

Cheers Zeb

Pericles
11-20-2011, 12:20 PM
Screw propulsion had some obvious potential advantages for warships over paddle propulsion. Firstly, paddlewheels were exposed to enemy fire in combat, whereas a propeller and its machinery were tucked away safely well below deck.

Secondly, the space taken up by paddlewheels restricted the number of guns a warship could carry, thus reducing its broadside. These potential advantages were well understood by the British Admiralty, but it was not convinced that the propeller was an effective propulsion system.

It was only in 1840, when the world's first propeller-driven steamship, SS Archimedes, successfully completed a series of trials against fast paddle-wheelers, that the Royal Navy decided to conduct further tests of the technology. For this purpose, the Royal Navy built Rattler.


http://en.wikipedia.org/wiki/HMS_Rattler_%281843%29

http://en.wikipedia.org/wiki/Paddle_steamer

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