Friction Steam Boiler

[rickoff]

Reply to Little Old Lady:

When you say his heater only produces 125,000 BTUs is there an implied timeframe that I am not aware of? 125,000 BTUs / second is much more power than 125,000 BTUs per year. Also, do you know how much wood is required to generate 125,000 BTUs? How was this number determined?

Hi Little Old Lady,

The British Thermal Unit (BTU) is widely used to rate the heating or cooling output of boilers, furnaces, air conditioners, and other such appliances. If a time factor is not given (which is often the case), it is understood that the given amount of BTU relates to a time duration of one hour. Don't feel bad. Many people do not understand this. That is why I feel it is preferable that all posters to the thread should use the term "BTU/hr" (BTU's per hour) when stating an output, even though the statement "125,000 BTU's" is also correct. This will help avoid any possible confusion.

Thanks, and best to all, Rick

[nonubbins]

Thank you Rick for clarifying that. Its easy to forget not everyone has the same experience as someone who reads or does it alot.

L.O.L. : Hang out a while and you'll learn.

[everwiser]

I get it now, Paul. Thanks. I wasn't aware that the outlet pressure would be that much lower than the input when it exited/routed from the the center.

[little_old_lady]

Thanks Rick, I searched the internet for that assumption, but it was hard to find. 125000 BTU/hr should easily power my 3HP steam engine.

Anyone know a good source for cheap, efficient, 3HP generators? Considering I don't need the ICE portion of traditional generators I would hate to pay $300 for a new one. It is also difficult to determine the efficiency of the electrical part of most generators because it is combined with the ICE eff. I have a 13KW PTO generator, but am concerned that a 3HP steam engine will not be able to drive it (even at a lower KW rating) anyone have experience with this?

DC or AC does not matter to me, my plan is to charge a bank of batteries and use an inverter to provide up to 10KW when I need it.

I will keep you all posted with my design / replication details. I am starting with a 6" disk (free scrap metal) and working with a mechanical engineer friend of mine whom has free access to a machine shop. It should be a very high quality replication.

Thoughts?

[rickoff]

Reply to Dan (Nonubbins):

1. How many cfm were required to make 200 hp?
2. I hope you or some one else builds one so we can see if it works. A Tesla turbine built with high efficiency will require R&D,$$$$$$$$$$, and powerful flow modeling software that doesn't exist yet, and optimized for your specific application. As it is, you'll be lucky to build one better than 20% efficient( I doubt even that ). And how many cfm or lbs/hr will yours require? Lloyd's heater only produces abour 125,000 btus.

Hi Dan,

In answer to your questions:
1. Tesla did build, and successfully tested, 110 and 200 hp versions of his turbine. In a New York Herald Tribune article dated October 15, 1911, and titled "Tesla's New Monarch of Machines," Nikola Tesla stated that, ""I have accomplished what mechanical engineers have been dreaming about ever since the invention of steam power. That is the perfect rotary engine. It happens that I have also produced an engine which will give at least twenty-five times as much power to a pound of weight as the lightest weight engine of any kind that has yet been produced." Long term testing in both on-site (laboratory) and off-site (commercial) applications verified that what Tesla claimed was in fact true.

Concerning the 200 hp model, this much we do know: In an article titled "The Rotory Heat Motor Reduced to its Simplest Terms," and published in the September 30, 1911 issue of Scientific American, the article states, "Mr. Tesla maintains that in the turbine which forms the subject of this article, he has carried the steam and gas motor a long step forward toward the maximum attainable efficiency, both theoretical and mechanical. That these claims are well founded is shown by the fact that in the plant at the Edison station, he is securing an output of 200 horse-power from a single-stage steam turbine with atmospheric exhaust, weighing less than 2 pounds per horse-power, which is contained within a space measuring 2 feet by 3 feet, by 2 feet in height, and which accomplishes these results with a thermal fall of only 130 BTU, that is, about one-third of the total drop available. Furthermore, considered from the mechanical standpoint, the turbine is astonishingly simple and economical in construction, and by the very nature of its construction, should prove to possess such a durability and freedom from wear and breakdown as to place it, in these respects, far in advance of any type of steam or gas motor of the present day."

Edit - The last paragraph of the Scientific American article, noted above, does in fact state that at full output of 200 hp, the turbine was running at 9,000 rpm, and that, "the consumption under these conditions of maximum output is 38 pounds of saturated steam per horse-power per hour." - Rick

Horsepower is more closely related to torque than to rpm, and it is a known fact that the Tesla Turbine develops its highest torque at low speeds - even when starting rotation from a standstill. That is what makes it a perfect drive motor for Lloyd Tanner's friction steamer, because a large quantity and/or high pressure of steam is not required to begin rotation of the friction rotor (or roller) drive shaft, and operating speed only needs to be 1800 rpm, which keeps the steam turbine in a low operating range. And since the turbine puts out the best torque at lower speeds, it is quite possible that the friction roller drive shaft could be geared to turn at 2 to 3 times the rpm speed of the steam turbine, and that the turbine would have sufficient torque to handle that load. What this means, of course, is that you could operate the turbine at 600 to 900 rpm, and achieve excellent results using "wet steam" (rather than super-heated steam), and at relatively low cfm rates with low pressure. You see that in the above example, the 200 hp single-stage turbine experienced only a 1/3 thermal drop. This high efficiency allows the still hot exhaust to be reintroduced to the boiler's feed water, thus greatly reducing the amount of heating required to sustain operation of the turbine. So you see the actual cfm of steam circulated through the turbine is far greater than the amount of steam that Lloyd's device would have to produce if the turbine's exhaust was simply vented to the atmosphere. Of course you don't need a 200 horsepower turbine to run Lloyd's device - a 1 hp model is sufficient to operate Lloyd's original vertical rotor design using two wood 4 x 4's, and a 10 hp turbine would operate a 4 ft long horizontal roller with up to 20 pieces of wood 4 x 4's. That's a lot of friction, and a lot of heat!

2. Luckily for us, Tesla already performed all the expensive R&D work, and he didn't use any software to accomplish that. Tesla was such a genius that he was able to model a prototype of something within his mind, and to build it from those "plans" alone - knowing exactly what to expect from the completed unit. Properly constructed, the Tesla turbine is highly efficient, and if coupled to a second Tesla turbine the efficiency rate can easily reach better than 90%. Some of Tesla's builds were verified at over 95% efficiency. For anyone interested in building a high efficiency Tesla turbine, I highly suggest that you become a member of the Tesla Engine Builders Association (TEBA), which can be found at: TESLA ENGINE BUILDERS ASSOCIATION
They have a wealth of information about proper construction of the turbine, including a 90 page manual and 2 hours of video instruction.
A split open view of Tesla's original 110 hp turbine, featuring a 20 pound disc assembly 9.750" in diameter and less than 2" wide, can be seen here: http://www.teslaengine.org/images/tesla1.jpg
With that much hp, and with these dimensions in mind, consider what a 10 hp turbine would look like - much smaller, of course! Let me remind everyone, however, that there are basically two factors relevant to the application for which the turbine will be used. The first is the output shaft speed desired, and the second is the horsepower (and torque) required. These factors are controlled by the diameter of the discs used for the disc assembly (also called the runner, as in the photo), and by the number of discs used. A larger diameter disc offers greater hp and torque, while a smaller diameter disc offers the highest possible rpm. Therefore, for example, one could utilize a turbine with 5 inch diameter discs to drive Lloyd's device at 1800 rpm, and couple the exhaust to a second turbine using 3 inch diameter discs to drive a generator head at 3600 rpm. The possibilites are only limited by one's imagination, and one's knowledge, skills, and abilities to replicate Tesla's turbine design. I know that a lot of people who have attempted builds have fallen short of the results they had hoped to achieve, but that is not a fault of Tesla's design. Rather, it is a result of the replicator's shortcomings. A well built Tesla turbine will offer stunning performance and efficiency.

Best regards,

Rick

[rickoff]

Reply to Little Old Lady:

Thanks Rick, I searched the internet for that assumption, but it was hard to find. 125000 BTU/hr should easily power my 3HP steam engine.

Anyone know a good source for cheap, efficient, 3HP generators? Considering I don't need the ICE portion of traditional generators I would hate to pay $300 for a new one. It is also difficult to determine the efficiency of the electrical part of most generators because it is combined with the ICE eff. I have a 13KW PTO generator, but am concerned that a 3HP steam engine will not be able to drive it (even at a lower KW rating) anyone have experience with this?

If you go to craigslist classifieds: jobs, housing, personals, for sale, services, community, events, forums, and use the search word "generator," you should be able to locate some good deals on generators located close to your vicinity. You may find one with a good generator head that needs engine work, and could pick that up for low cost. Expect to pay around $300 or so for a 5 kw generator with an engine still in good running condition. Nearly anyone can supply their household electrical needs with a 5 kw generator, unless you are using electric heat. Most household electric supplies have the capacity to deliver far more than 5 kw, but that is because they are designed to withstand extreme demands - such as an electric stove, water heater, refrigerator, oven, dishwasher, clothes washer, clothes dryer, hair dryer, toaster, and 2 or three TV sets all running at the same time. Wise management of electrical usage places far smaller demands on your supply. In other words, you do 1 or 2 of the above things at the same time, while other appliances are left switched off. In doing so, you can actually run your household from a 3kw supply. So going with a 5kw head will actually give you some reserve power. Generally speaking, a gas engine of about 2 hp per kw of electric production is required to drive a generator head, so 10 hp would be about right for a 5 kw generator under full load.

One might also consider constructing their own generator using a Tesla reciprocating engine having an external, shaft mounted, permanent magnet which passes through a stationary coil. At a reciprocating speed of 60 cycles per second, you would produce alternating current at the correct frequency for household use. To match supply voltage of 110v, the magnet stength and the coil windings would need to be determined. I may post some further thoughts on this adaptation if any of you are interested.

Best wishes,

Rick

[rickoff]

Reply to Paul (rileydad48):

This is where I want to be... and I think it just might be possible with Tesla and Tanner together..

I agree, Paul, and I think that is exactly where many of us would like to be at eventually. Thanks for the great diagram.

Rick

[rileydad48]

Rick..
Thanks for the great post.. There's one thing that I am alittle confused about though. While Tesla's turbine retains a lot of the heat, it losses substantial pressure at the exhaust. Will there be enough pressure to run a secound turbine or will the heat alone be enough.. or will an air pump (as in my idea) really be needed?? I was thinking that the pressure would be too
low to reach a heat exchanger some distance from the turbine..?? If I'm wrong then I have to say I'm sorry to "Everwiser"... which is not a problem..
I've been wrong before...LOL

Thanks
Paul

[rickoff]

Reply to Paul (rileydad48):

While Tesla's turbine retains a lot of the heat, it losses substantial pressure at the exhaust. Will there be enough pressure to run a secound turbine or will the heat alone be enough.. or will an air pump (as in my idea) really be needed?? I was thinking that the pressure would be too low to reach a heat exchanger some distance from the turbine..??

Hi Paul,

Thanks for bringing up these questions. To help answer them, let's first go back to your post #250 of this thread, in which you related the following facts:

Using 125 psi and 300 degree heat the turbine produced 200 HP. The Fasinating thing about the turbine is that the exhaust temperature was reduced by 1/3 and the pressure dropped from 125psi to less than 3psi...

Now keep in mind that this 200 hp turbine was operating at the relatively low pressure of just 125 psi, and that the steam was introduced to the turbine at 300F degrees. Reducing the temperature by 1/3 at the exhaust brings the temperature to 200F degrees. At 200F degrees the steam has effectively been fully condensed back into hot water below the boiling point of 212F degrees, where it can be reintroduced as boiler feed water requiring a rise in temperature of only 100F degrees before being reintroduced to the turbine. It is the rapdily expanding nature of the generated steam that creates the 125 psi operating pressure, and the condensing effect of the steam to water conversion that causes the pressure to drop back to normal atmospheric (14.7 psi) or less. This particular installation, at the Edison Waterside Station in New York City, was meant to be mated to an electrical generator. According to the article in the September 30, 1911 issue of Scientific American, which I pointed to in my post #260, the turbine's rotor consisted of "25 flat steel disks, one thirty-second of an inch in thickness, of hardened and carefully tempered steel. The rotor as assembled is 3 1/2 inches wide on the face, by 18 inches in diameter." This large diameter was obviously chosen because of the resultant horsepower and torque, which was desirable in order to efficiently drive a large generator. Since the steam spirals inwards from the entry point to the central exit port of each disc, a large diameter disc effectively delays the exit of the steam and utilizes the working pressure of the steam to full advantage.

If you want to have steam and pressure left over for additional utilization after passing through the turbine, you can do 1 or the other of two things (or both, for that matter):
1. Design the turbine with smaller diameter discs. This reduces the spiral path length and underutilizes the available steam volume and pressure, allowing a second turbine to be powered by the exhaust from the first turbine.
2. Increase the steam volume and pressure. In speaking of Tesla's 200 hp turbine in this regard, the Scientific American article stated that, "it should be noted that although the experimental plant at the Waterside station develops 200 horse-power with 125 pounds at the supply pipe and free exhaust, it could show an output of 300 horse-power with the full pressure of the Edison [steam] supply circuit. Furthermore, Mr. Tesla states that if it were compounded and the exhaust were led to a low pressure unit, carrying about three times the number of disks contained in the high pressure element, with connection to a condenser affording 28-1/2 to 29 inches of vacuum, the results obtained in the present high-pressure machine indicate that the compound unit would give an output of 600 horse-power, without great increase of dimensions. This estimate is conservative."

So compounding is definitely not only possible, but also advantageous with a smaller diameter Tesla turbine such as we would use with Lloyd's friction steamer, and we therefore do not require use of higher steam pressure as in option #2 above. You could use the compounding effect to drive a second turbine capable of boosting the power to the friction roller shaft, which would help maintain a self runner, and use a small Tesla pump (driven by the friction roller shaft) to circulate water to a radiator system and/or hot water holding tank. The Scientific American article cited a small Tesla pump, saying, "This little pump, driven by an electric motor of 1/12 horse-power, delivers 40 gallons per minute against a head of 9 feet." With that kind of pumping, and requiring so little drive power, it would be foolhardy and wasteful not to take advantage of it somehow, as I think you will agree.

Speaking of this amazing yet small aluminum cased pump (which was said to be the size of a small mechanical alarm clock) in a New York Herald Tribune article dated October 15, 1911, Tesla said, "This is only a toy. There are only half a dozen disks -- 'runners', I call them -- each less than three inches in diameter, inside of that case. No vanes, blades or attachments of any kind. Just perfectly smooth, flat disks revolving in their own planes and pumping water because of the viscosity and adhesion of the fluid. One such pump now in operation, with eight disks, eighteen inches in diameter, pumps four thousand gallons a minute to a height of 360 feet."

We certainly dont need to go to those extents, but the pumping of air or water, which you include in your plans, is quite feasible.

Good luck to you Paul, and do keep us informed of design changes or enhancements, along with construction photos and/or video links showing the work in progess at various stages.

Best wishes,

Rick

[Alana]

Thanks everybody for their very interesting posts and enthusiasm. It's impressiv.
In every post Tesla is involved I get a little bit sceptical. I don't know what to make of this? We all know his inventions and his patents. Most of them are only ideas. I think most of the inventions of Tesla are popular myths.
When it is so easy why we haven't yet this engines? Furthermore: I never heard from Tesla turbines who are over 95% efficient. I only heard from 80 %.

I hope I am wrong with my scepticism.

Alana

[rileydad48]

Hi everyone....

Tesla once said " In a 100 years it would be his time" Well, it must be getting there, because last night on the History Channel "Modern Marvels", they devoted an hour program to the life and inventions of Nikola Tesla. Very good program. Of course it was very general on the specificates of his inventions, but all the same very interesting..
Knowing the History Channel.. they will reapeat it several times before its thru. Look for it in the guide... Just thought someone might want to know..

Paul

[rickoff]

Reply to Alana:

Thanks everybody for their very interesting posts and enthusiasm. It's impressiv.
In every post Tesla is involved I get a little bit sceptical. I don't know what to make of this? We all know his inventions and his patents. Most of them are only ideas. I think most of the inventions of Tesla are popular myths.
When it is so easy why we haven't yet this engines? Furthermore: I never heard from Tesla turbines who are over 95% efficient. I only heard from 80 %.

I hope I am wrong with my scepticism.

Alana

Hi Alana,

Why so skeptical? The US and British Patent Offices issued a great many patents to Tesla, and this is not lightly done on the basis of concept alone. Patent examiners must be shown proof that a concept actually works as stated, and that claims of test results can be substantiated and verified, before patent rights are granted. Tesla's turbines were far from being "popular myths," as you say. Several photos exist which show numerous builds and applications of his disc turbines. Many men with scientific and engineering backgrounds witnessed the turbines in action, and offered validation of Tesla's claims and test results. All of us bear witness to Tesla's creative genius each time that we make use of AC power, but first and foremost Tesla was a mechanical engineer. His development of the Tesla Turbine was the result of many years of research and development on his part.

Alana, you seem to be asking why Tesla's turbine design appears to have been rejected, while his electrical discoveries and inventions gained widespread use. Perhaps the best answer to this is written in Tesla's own words, from his 1919 autobiography titled My Inventions.

"My alternating system of power transmission came at a psychological moment, as a long-sought answer to pressing industrial questions, and altho considerable resistance had to be overcome and opposing interests reconciled, as usual, the commercial introduction could not be long delayed. Now, compare this situation with that confronting my turbine, for example. One should think that so simple and beautiful an invention, possessing many features of an ideal motor, should be adopted at once and, undoubtedly, it would under similar conditions. But the prospective effect of the rotating field was not to render worthless existing machinery; on the contrary, it was to give it additional value. The system lent itself to new enterprise as well as to improvement of the old. My turbine is an advance of a character entirely different. It is a radical departure in the sense that its success would mean the abandonment of the antiquated types of prime movers on which billions of dollars have been spent. Under such circumstances the progress must needs be slow and perhaps the greatest impediment is encountered in the prejudicial opinions created in the minds of experts by organized opposition." - Nikola Tesla

I encourage you to learn more about Tesla, his experiments, and his many wonderful inventions, including the Tesla Turbine. Please review the following websites, for starters:
www.Magnetricity.com ... Homepage

Nikola Tesla: Disk Turbine / Pump (Articles, patents, links)

TESLA ENGINE BUILDERS ASSOCIATION

Best wishes,

Rick

[little_old_lady]

little_old_lady:
Paul said it well but I have one question. Where is the motive force for the friction heater(s) coming from? There is no way it will be a self-runner and turn a generator also! Can you imagine the fuel/electric bill? You'll be swapping money with the fuel/electric company!

Paul, you seem to be of the opinion that all of the heat energy comes from the friction. I am of the opinion that the wood is combusting (white ash left behind) and that the friction is a small input energy to release the energy stored in the wood. Further more, I am of the opinion that much more of the energy in wood and released via heat of combustion is captured because it doesn't go up the chimney. Given that a 1 HP motor can burn enough wood to power a 3 to 5HP steam engine, then that means that the steam engine could use 1 HP to keep the disk spinning and 2 HP to generate surplus power. It is from this understanding that I do not believe that "break pads" will work equally as well as wood. Here you only have friction and no combustion.

If his device really provides a better way to convert mechanical energy into friction heat then maybe a break pad system could work, but I doubt it works "enough better" in this "mode of operation" to generate enough steam to even power itself due to the heat of vaporization which is lost plus the loses in steam engines, turbines, or tesla turbines. Clearly energy must be coming from the wood.

[little_old_lady]

Paul, you ...

Sorry Paul, I meant nonnubbins.

[nonubbins]

L.O.L.;

1. I called it a friction heater because thats what Lloyd called it all along. And I had thought, like you and others here, that the wood was combusting also. The more I look at it, the more I think it is friction at work, at least partly. Burning wood doesn't actually burn. It starts pyrolysis at about 450F and dry oak auto-ignites at about 8-900F. The moisture outgases first as it boils at 212F, then as the moisture level falls the temp can rise to start the wood gas process.(pyrolysis) Light a match and look at it closely. There is a space between the flame and the wood. The heat from the flame is "cooking" the wood gas out of the wood. Thats why you need dry wood to start a fire easily. And the friction heater uses green oak! The testing I've done proves to me that green is better than dry. So until proven otherwise, IMHO there is more friction going on than most will admit. Maybe there is something happening at the atomic level!?

2. Where are you getting the 1 hp motor powering a 3-5 hp steam engine? Lloyd's new heater design puts out 125,000 BTU/hr which MIGHT run a 3 hp engine! And I think I remember seeing Rick mention 4hp or so to drive it. IMHO thats optimistic! Thats where the Tesla turbine came swooping in to save the day at 95% efficiency! All I'm saying is that the modern steam engine(not the Green engine) is our only hope to have a self-runner IMHO. And lets face it, if its not a self-runner, then its a boat anchor. Again, prove me wrong. I would love to be wrong about this but instinct prevails for now. Meanwhile, I'll keep designing the wood gasifier boiler that I'd like to build.