The New Age of Sail

(Bob LLewellyn) #83

Thanks for that link Tom… This is a new one for me. Even the forced pressure ones that I knew of would struggle at 100 ft. 350 feet is really impressive but I have to admit, my knowledge base is at least 25 years old.

(.) #85

This topic is not about nuclear reactors.

(noboxes) #87

This topic is not about what this topic is not about.

(Bob LLewellyn) #88

The topic is not about pumps, to be sure but why couldn’t we use pneumatic as a base of propulsion. The pressure well pump just forced air down into well to run a pneumatic pump. Anyone who has ever used air tools know how much force those things can have. And pressurized air can be stored. If we need to compensate for drift, we could use something like an air drill to turn the props. We can safely run pressurized airlines all over the place to run pumps, generators, motors (winches, lifts, desalinizers) the list goes on. We all were discussing 120V ac or 12/24/48 VDC. It is dangerous to have high voltage around water but high pressure is not a problem. Maybe this is the new age of sails.

(Larry G) #91

Indeed, I’ve seen a number of laceration accidents from misused retail grade pressure washers- and that’s only 1200-1500 PSI. I’ve personally seen a guy cut partway through a couple toes using a 1300 PSI pressure washer on his sidewalk while wearing flipflops. It was super quick, incredibly painful, and bled a LOT. Professional pressure washers go 4500 PSI easily.

SCUBA tanks routinely go 3300 PSI (Common US Yoke valves) to 4500 PSI (DIN valves) and require special training to fill and service. Annual visual inspection and regular hydrostatic inspection is necessary to maintain them in safe conditions- hydrostatic test are done inside reinforced concrete wells because failure at those pressures is usually catastrophic and VERY dangerous.

I recently had to counsel a co-worker on the danger of his home air compressor lines and maintaining them in a charged state- he had never considered it, but saw the danger once I pointed it out.

Hydraulics and pneumatics are very useful, but can be dangerous.

(Bob LLewellyn) #92

I as thinking more along the lines of air tools. The recommended pressure for those is 90 PSI. We normally set the regulator at 100 psi to keep the pressure up while the tools are in use. Again, it has been a few years since I was playing with tools like that, so things might have changed. But 3300 psi does seem to be awfully high. I would be afraid to use tools under that kind of pressure. If there has been a change from 100 psi, I hope someone would advise me on that.

(Bob LLewellyn) #94

Yep, I used to work on those things. Keeping even something of this size and weight is not difficult because of inertia. Making all that weight change the rate of speed takes an unreal amount of effort.

However, we’re not working with something that massive. A barge home is relatively light. My brother fixes up boats for resale. He has air tools and a good size compressor. Let me see if he can find out how many rpm a two foot screw would realize under the resistance of water. In fact, he may already know. If we can find that out, we may have an idea of how much boat we can push with a 90 lb air drill.

(Bob LLewellyn) #97

Of course but most of the ocean is too deep to work with, this is why we brainstorm, to get ideas that won’t work but will lead you to other ideas that won’t work. and so on until you accidentally find something that changes the world.

You seem to be under the impression that to get more work, you need to increase the pressure. Think of it in terms of electricity. If you increase the voltage, you get more watts which does more work until the part burns out because it can’t handle the voltage. But you can get a 12 volt refrigerator to freeze your food just as you can with 120 volts. It’s not just the pressure but the current flow as well that gives you energy.

If you need more force to move the screws, you can keep the pressure at 90 lbs. but increase the amount of air pumped through the lines. By pumping more air to the end point use, you could run 2 or more air drills or one twice the size or larger.

You can see that if we had 2 or more air drills turning one prop shaft, it can be moved very well with 90 lbs. pressure.

The real problem is that it is noisy. Real noisy. I suppose the sound could be baffled but it would take up space and add to the cost.

(Bob LLewellyn) #99

Or an electric motor that that will draw 3 Kilowatts. One horse power is roughly 748 watts. But you are missing a very important point. If you only use existing technology to do something, you never create something new. You need to first think outside the box. See in your head a new way to do something that no one else has tried.

The whole idea of brainstorming is to dream of something better and see if you can make something better. It isn’t useful to rip an idea apart before it has been constructed, and new ideas never come pre-assembled.

You will do yourself a huge favor by reading that book that I recently posted a link for. “How to Make friends and influence people” by Dale Carnegie. That one book will add something like 10% increase in earnings all the rest of your life. Going through life without the knowledge in these recommended books, is like going through life with shoes that don’t fit. You will get through it, but it will always be a struggle. Why not get to where you’re going in comfort?

I taught my own sons this very powerful fact of life. Invest in a good, comfortable pair of shoes and learn effective communication. They listened, they are doing very well.

(Larry G) #100

power systems easily produce linear motion using hydraulic or pneumatic cylinders, whereas electrical and mechanical methods usually must use a mechanical device to convert rotational motion to linear.

Pneumatic converted to rotational is sort of a double translation. Not efficient. Pneumatic is great to transmitting power in mobile, flexible ways that need short bursts of energy (impact wrenches) especially for things. That might heat up too much using electric motors, but not for steady applications.

I am thinking of a Korean War era tug boat moored near me. It has a V8 Diesel engine with an electric starter. This motor powers an air compressor to fill a reservoir. That reservoir powers a pneumatic starter for the main engine, a very large diesel. The main engine is direct drive with no transmission. You have to sop it and start it in the other direction to reverse thrust.

So think about the biggest air compressor your ever seen (V8 diesel) and consider it can only start an engine of the size needed to push large ships around once it has built up pressure in the reservoir. It can’t directly move the ship.

(Bob LLewellyn) #101

Now see, I didn’t know that. Oh well, back to the drawing-board.

(noboxes) #102

Why would they use the diesel’s starter motor to power an air compressor?

(Larry G) #104

That’s not what I said.

Standard Marine V8 Diesel engine. Started from battery with a standard marine electric starter. Once running, it powers an air compressor which fills a large reservoir with pressurized air. Once the reservoir is pressurized, that pressure is used to start the main engine.

(Larry G) #106

This is the problem with being a pedantic boor. Clear communication is less important than trying to be “right”. The context here is clear in the overall paragraphs. I might have been more consistent with the terms Engine and Motor. It would not change the meaning.

You are incorrect:

1. a comparatively small and powerful engine, especially an internal-combustion engine in an automobile, motorboat, or the like.
Synonym: Engine

Example: "The V8 motor powers an air compressor to start the main engine."
Example: The Ford Motor Company (not an electric motor company).
Example: General Motors Corporation (also not electric).

The two terms are mostly interchangeable. We don’t have electric engines (Although I could find some historic uses of the term, I seem to recall Jules Verne used the term “mighty electric engines” in reference to the Nautilus in “20,000 Leagues”), but a motor can be electric or internal combustion, as long as it is providing motive force.

(Bob LLewellyn) #108

Cow = motorcycle…

(Larry G) #110

Actually, regionalisms are absolutely valid. People rarely say "Tis or “Tisn’t” any more. People don’t say “Od’s Bodkin”. But would you say that Shakespeare’s plays aren’t acceptable? Good luck in imposing your personal viewpoint on the uncaring universe.

Pronounce things differently from the people around you, and it marks you as an outsider and impedes social bonding and communication. There is NO “perfect” use of language. Language in general is a TOOL, Not a mandatory STANDARD, not an absolute fixed object. If you get your meaning across effectively, you have used language correctly. “Everyone else does it”… yes, exactly. You could use Esperanto perfectly according to the published grammar book. If nobody else uses Esperanto, you have failed to communicate. If you use your “perfect” Esperanto and some group of people have developed a regional pronunciation and grammatical variation through daily usage and reliance upon the language as a primary means of communication, then you would be “wrong” to insist on your way. If you could magically communicate with a 1st century Roman Legionnaire, I can guarantee that even perfect grammar school Latin of recent centuries would not effectively communicate with him, no matter how precise your declensions.

Language is ALWAYS a mutually negotiated protocol. Across generations, across regions, across specific occupations, the meaning of specific words, their pronunciation, it all is negotiable and changes from time to time in both specific and general usage. Get over it.

(Bob LLewellyn) #111

Your point is well made but any language that was taught to the children as a universal world language, as their second language would be a great asset to the whole world’s unity. The problem is emotions. People hate the US so would resist using English as the universal language. I resist it too as to complicated. An intentional world language should be developed so that it would be easy for the greatest part of the population to learn.
(greatest here means most not those of superior ranking.)

If we could get a petition up to send to UN rep Nikki Haley, she could get such a movement started. The UN should do something to bring unity of some type to the world and this is just a simple inexpensive way to begin.

It would do so much good that - it will never happen. Where would the war merchants be if everyone started talking about their problems.

(Larry G) #112

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