Solomon Technologies - "Electric Wheel" electric motor propulsion systems

Discussion in 'Hybrid' started by lockhughes, Jun 18, 2002.

  1. Portager
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    Portager Senior Member

    OK, maybe the duty cycle is different, but you still need to include it in the MTBF calculations. The point is that it isn't correct to compare the MTBF of an electric motor to that of a diesel engine. You need to compare the MTBF of the system (with realistic duty cycles). Now that would be useful information.

    I would do this and I know I would find just the opposite, but that wouldn't be fare. AC generator engines do not last nearly as long as main engines because they must maintain a constant speed, regardless of the load, to produce power at the correct frequency. DC generators claimed to last longer, but since very few boats have adopted them so far, it would be difficult to find valid life cycle data.

    On the subject of warm up time. Do your generators allow the engine to warm up at low speed before going to their optimum speed and loading?

    I looked into the US Navy's selection of diesel electric propulsion for DDX. www.ces.clemson.edu/powsys2002/ppt/P5/TB.ppt The enabling technology is super conducting motors, which are the key to making an electric drive energy efficient. http://www.marinelog.com/DOCS/NEWS/MMNov27.html .

    Cheers;
    Mike Schooley
     
  2. lockhughes
    Joined: Jun 2002
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    lockhughes ElectricGuy

    First boats, THEN the world <grin>
    L
     
  3. trouty

    trouty Guest

    Doubting Thomas? ;o)

    :rolleyes: Like this is "new" technology guys?...Oh C'mon - this isn't new or that hard to understand - all you have to do is sit on your "Mass" - ive derriere's and read :D - how hards that?...

    OK, you darn Americans started all this off you know - hubbard for a start took a lot of the stuff Nicola Tesla started and ran with it for a while - he'd a done a lot better if the OSS (later to become your CIA) hadn't roped him into working for them, where he eventually headed your 60's LSD program....

    OK, you want to follow it all thru eh?

    Try these few links for starters and sorta work your way up to the tough stuff. If I, a simple layman (who can get + and - mixed up jumpstarting a car with a red n black leads) can understand it - I'm quite sure an electric wheel inventor should have no trubble! :p

    Start with Hubbard and work your way to Bearden...

    http://www.rexresearch.com/hubbard/hubbard.htm

    http://www.altenergy-pro.com/device09-2.htm

    http://www.nuenergy.org/jakelj.htm

    http://www.cheniere.org/techpapers/Final Secret 9 Feb 1993/index.html


    You all seem to accept that Nuclear energy works - yet seem to ridicule the idea, that any other understanding of electrical / magnetic, gravitic energy principles could deliver us other alternative energy sources from this universe, which is quite a contradiction in terms don't you think?

    I mean - the energy trapped within an atom is so powerfull it could destry the entire world - and yet the energy in the ether of space (time) isn't capable of doing something similar?

    Read about Hubbles electric powered BOAT guys - sailed contunous for 3 days in the US in the 1920's without external power source!

    Here we are almost 100 years later and esteemed boat designers / and supposed electrical experts still haven't cottoned on yet? :rolleyes:

    Gimme a break - If I jolted your a$$es with 1000 volts from a MEG , you'd still be sitting here chewing bandwidth debating the merits of batterys!:eek: :D :rolleyes: :p

    Just take the time out from your busy routines guys - to have a little read here n there and to consider the "alternate" electrical theorys postulated and you'll see that tyhey are in fact quite valid - they do work and have worked for almost 100 years now.

    I'll talk electric propulsion of boats with you - WHEN you catch up...ok?

    Cheers!
     
  4. trouty

    trouty Guest

    An addendum for doubting Thomas! ;o)

    Tom,

    Indeed why mess round with boats - when it can in fact power the world!.

    Sitting here as we are on the verge of WW3, the US about to invade Iraq, to secure the last of the worlds fossil fuel oil / gas, for the USA's insatiable (and wastefulll IMHO) appetite for energy, having just secured the entire Caspian basin reserves in it's recent "Pipemenistan" bombing campaign the question you ask is quite ironic really.

    Your own citizens have been the principal discoverers of alternate electrical energy for almost 100 years...and yet here the USA is usurping the worlds last fossil fuel reserves from the very towel headed, mud hut living afghanis and soon Iraqi's with a carpet of bombs.

    Why?

    Coz the USA can't function (read survive) unless boat fuel is a back a gallon! (or less).:rolleyes:

    Since the arabs screwed the oil spiggotts off - the US economy is collapsing daily...as evidenced by the recent continuing market collapse.

    Why a buck a gallon to power a boat?

    Cargo ships once out at sea and full steam - switch from light diesel to running on bunker oil - at about 6c a gallon!

    The world is about to go to hell in a handbasket - over the US' insatiable appetite for oil - so much so that you've just taken delivery of your first shipment of "Russian" oil! :eek:

    Hows it feel to be dependant on your former cold war enemys for oil now? :(

    I'd say it's high time the US took a long hard look at the Texas oil cowboys running the country, and started to make inroads into their alternate technologies BEFORE we - the rest of the world get saddled with the bio warfare and nuclear fallout which will be inevitably associated with the US current insatiable thirst for oil.

    This joke is a little sad - albeit quite funny, given the current world situation,...

    3 boat captains all standing on a bridge fishing

    The first Capt, a full blood Iroquoi Injun, laments the fact - that his people are almost totally extinct now, thru disease, interbreeding with the white man, firewater abuse etc..

    The second Capt, a Muslim, says how his people are doing great - they all sit for 18 hours a day, bangin their towel heads against a wall and reading the Koran, they breed like flies, and now occupy fully 70% of the Earths habitable landmass, increasing 5% per annum!

    The 3rd Capt, a Texas oilman, leans back against the bridge railing, rolls a smoke with one hand, lights the match on the a$$ of his rawhide jeans, ignites the smoke, draws back a deep lung fulla smoke, and slowly exhales it all - all the while looking the Muslim Capt. square in the eyes...and says...

    "Yeah, but - we aint played Cowboys n Muslims Yet!" ;) :D :p

    Soooo...

    Why boats?...and not the world?
    ...ahh scuse me - who said I wasn't plannin to power the whole world? :cool: :p

    Remeber, vote trouty 1 for benevolent dictater!;) :D

    Cheers!
     
  5. ewhel
    Joined: Jun 2002
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    ewhel Junior Member

    Cheers ? After that lambasting?....well we could grind England up and use it for top soil in Texas....na....you Englishmen are kinda cool...yes we are 20% of the worlds population using 80% of the worlds energy but we also provide the police force to keep it safe! Yes we are a target for every jealous tyrant....but they squash like bugs when they get too far out of line. How about all the cool things that have come from our think tanks...which, by the way, are usually an excellent blend of humans from all cultures....that's what makes America great....we are the world...here there are Jews that marry Muslims...and Russians that marry Pol's and Germans. We need that energy to promote life and liberty and the pursuit of....well....protecting every one else.
     
  6. ewhel
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    ewhel Junior Member

    Mike...the reason we sometimes leave the MTBF data out on diesels is that we don't really need them...some of our customers are doing just fine on regeneration with no fossil fuel on the boat at all..They use solar and shore power to charge. But most of the cruisers use generators...and we have them on our demo boats here...
    You are looking at the "old" electric ships...the new ones will not rely on superconductors...that's the only AC and Traction drive initiatives...the new DD-X Electric Ship will have DC generators and multi phase PWM DC motors. This program was started as DD-21 and is now DD-X. Why...it's just more efficient and less cumbersome to work with. It's also modular.....I replaced a 540lb. diesel&Transmission with a 140lb Generator and 60 lb motor....either the motor or generator I can get out to replace with my bare hands...the 540lb diesel took pulleys and winches and 3 men and a lot of skinned fingers. Modularity is a wonderful thing for marine propulsion....and did I tell you that our motors will operate under water?...or with a gallon of water in them. Sure the generator may break or you pick up a load of bad fuel...but the motor will still dock the boat....that generator is just one way to get energy. Can you imagine this scenario....I get bad fuel...the gen dies....I send out distress call....the DNR(in Maryland that's department of natural resources) or the Coast Guard shows up....or Tow Boats US....and I can tell them...No I don't need to be towed all the way back to land...just give me a recharge! For sailboats...they just wait for wind....do some sailing...and they recharge themselves. How does that affect MTBF?
     
  7. trouty

    trouty Guest

    Hmmm Lambasting?....nah that was just a liverpool kiss! ;o)

    OK, so you can't get the hang of MEGS - all too complicated..

    So - no MEG to power the Electric wheel motor then!:(

    Ok - well - how about an Orgone implosion powered "Joe water cell"? :confused:

    You layman types should be able to rig up one a these no sweat! ;)

    http://educate-yourself.org/fejoewatercell.html

    Or those who find beardens technobabble a little difficult to follow might prefer this recent synopsis for the layman.

    http://educate-yourself.org/megscalardevice29mar02.html

    This extract gives a few tantalising details about timing and availability.

    "The first MEG units to be produced for sale will output 2.5 kilowatts of free electricity. Forever. They should be in production about a year from now. Facilities for manufacturing the device are being set up in an unnamed "friendly nation."

    This free electricity will flow indefinitely, without much, or any maintenance. The units may be hooked together to provide more wattage, so four of them would provide 10 kilowatts. After some production experience units will be made which output 10 kilowatts each. With a couple of those units a house could get off the electrical grid."

    ......

    So - what sorta displacement speed can we get outta our Ferry using the electric wheel whith 10 kilowatts input? :D

    Will we be able to turn it into a hover ferry?

    The mind Boggles.....Cold electricity anyone?

    http://educate-yourself.org/coldelectricityvideo.html

    Of course we have the usual array of oxygen / hydrogen cells etc http://educate-yourself.org/fewaterasfuel28jan02.html

    Soooo - ahhh why is it again we need to monopolise the worlds oil supplies?...the rationale for that musta escaped me somewhere!

    Cheers..
     
  8. tom28571
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    tom28571 Senior Member

    OK Trouty,

    I'm going to try to explore this Scalar Electromagnetics to see if I can get some understanding of it. Bearden claims that scalar physics does not violate the inviolate energy laws that were drumed into me in school and by a life of work and observation of physical phenomena. Unlike you, I have had formal and informal training in physical sciences. Maybe that is the root of my skepticism.

    However, let me say that if sliced bread or any other great advance in history had you as an introductory ambassador, we would all still be painting pictures on the walls of caves.
     
  9. Portager
    Joined: May 2002
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    Portager Senior Member

  10. trouty

    trouty Guest

    Sheesh

    5 pages talking about batterys!:rolleyes:

    Ya might as well have spent 5 pages talkin about coal fired steam boilers for vessel propulsion - face it guys - outdated technology! :D :p

    Next you'll be wantin to put a sail on this thing!;)

    hehehe...

    Ohhh - and Tom...ahh - you don't still paint the walls a your cave?... sheesh we still do..."hey honey - throw another brontosaurus rib on the fire will ya - I hear the Rubbles are due over for a feed soon!" :D

    Cheers!
    C'mon Mr Slade - pull the goddam tarradactyles tail already will ya - I wanna knock off n go bowlin with Barney! nyuk nyuk nyuk!
    :cool: :D ;)
     
  11. ewhel
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    ewhel Junior Member

    Trouty,

    The only thing I can say is I love free energy, that's why I sail a boat that regenerates....and you mentioned Orgon energy .....have you read Wilhelm Reicht? Seems you might be on to something.....I also love Tessla...and at Solomon we don't care where the energy comes from....as batteries, ultra capacitors, Tessla coils, Solar , fuel cells,flywheel storage batteries or what ever new improvements that get invented, they only enhance what we are doing. 90% of the systems on the boat are electric already...usually only propulsion is fossil fuel....why not make them all electric...and if we have to burn fossil fuel because of power density...let's always do it at the highest possible efficiency(least emissions naturally follows). Let's also allow for other renewable inputs that can then enhance total system efficiency.
     
  12. trouty

    trouty Guest

    No "t"!

    Wilhelm Reich...no "t" and yes - I've read a little of him.

    Another of the free energy professors that seems to have been deliberately "oblitereted" bye the military/industrial/oil interests of the USA!

    2007 his scientific works are due for release - he claimed the world would not be ready for his work for at least 50 years after his death (in 1957).

    An interesting synopsis of his orgone theory here.

    http://www.orgone.org/articles/ax9rourke-a.htm

    Cheers!

    :idea:
     
  13. ewhel
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    ewhel Junior Member

    Sorry for the diversion from electric boats in this forum...but I have read one of Wilhelm's books and it was incredible...they put Wilhelm in jail, where he died of pneumonia, but his lab assistants went into hiding and eventually republished his books and lab tests in the 70's. Made me want to build and Orgon box 10 years ago.
    Now...back to Electric Drive systems....what is horsepower? Came from horses then was converted to everything that moved...but what assumptions were made during that conversion. What was the controversy over steam engins when they came out....relative to other horsepower calculations....? Hint....Torque...is all important...and all calculations are relative...and over the years the relativity has been specifically focused of FF motors...that have been overstated, measured in a range where you don't or can't use them, based on fuel/oil used and accepted as good enough for Government work....Not by me.
     
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  15. Mike D
    Joined: Sep 2002
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    Mike D Senior Member

    I am not sure if this is the right thread to use or not. The tangled yarns that contributors are spinning as they weave, shuttle back and forth is truly warped, and I feel stranded or at least entwined or enlaced in a knit of knots with knuts.

    This first paragraph refers to crazies on various other sites, as we all know there are no crazies on this site

    There are many points raised and some of them are inter-related so it becomes difficult to address one subject with raising others. So let me work my way through a few.

    Propellers
    Prof. Burrill was the acknowledged world’s expert on propellers about 60 years ago. Much of what he did is classic. For example, in the 30’s he developed a new type of propeller and gave permission to a Dutch researcher to use it and further develop it if he wished – this is now the Wageningen B series and it crops up all over the net. Cavitation had become a serious problem and he developed a new approach, published his findings and a diagram he prepared is still used. The US Navy, for example, calls for its use in propeller design on new projects etc – it also crops up on the net on many sites. Well, Prof Burrill was fond of saying that it was simple to design a propeller but very difficult to design a good one.

    On every site I have visited that deals with boats I find the same theme and Prof. Burrill was on the nose!. I have seen advice from one boater to another suggesting he takes such and such a propeller and tries it instead of so and so’s. So when I read of the impossible claims of efficiencies rising by extraordinary jumps I am no longer surprised.

    Often the original propeller was a dreadful choice so almost anything would have worked better. Although I hesitate to advise on the total boat I can discuss the propeller and drive train and speak from years of hands-on experience. There is a world of difference in the operating characteristics of small, fast, boat propellers and big, slow, ship propellers but they all obey the same laws.

    There is a propeller design diagram that will solve any design problem and it is a pain in the *** to use. The Kt-Kq diagram but it is specific to a propeller type and you can’t use it for a Wageningen and a Gawn, you can only use THE Wageningen or THE Gawn types or whatever type or manufacturer you are using. The diagram's name is simply K meaning a coefficient and t for thrust or what you get out of the propeller and q for torque (hello ewhel) or what you put into it.

    Any fixed blade propeller has a design operating condition and it has a small range beyond which all hell breaks loose. The design condition is basically what vessel speed and propeller rpm do you want or what speed and diameter do you want? So the propeller characteristics of rpm, power hence torque, diameter, blade area ratio and pitch can be matched to the vessel and its drag. Then figure out the other speeds with the screw in an off-design condition.

    Naturally if you change the ship or boat speed the resistance changes and there is a different demand on the drive system or engine and this causes a drop in propeller efficiency because the operating range or band is quite narrow.

    At low speeds the power changes in proportion to the cube of the speed approximately. By slow I mean the famous V/RootL so the things I am most familiar with are say around 500 feet or so running at say 15 knots giving V/RootL =0.67 whereas a boat 25 feet long at the same speed has V/RootL = 3. At such high values the cube law no longer applies and power will vary with speed to the sixth or higher power. So a change of one knot on the boat has a much greater effect on proportional power demand than on the big ship. And there’s the problem and why there are so many conflicting experiences in the boating community – there is no such thing as an efficient propeller for a fast boat unless it always goes fast.

    It has too many operating regimes with conflicting requirements so a good propeller at say 10 knots is not very good at 15 and a disaster at 25. There is a dramatic improvement when a Controllable Pitch (CP) propeller is used – not Variable Pitch – almost ALL propellers are variable pitch. The ordinary propeller is NOT fixed pitch – it is fixed blade. The pitch quoted is normally the pitch at 70% of the propeller radius from the shaft centre-line. The CP propeller is much more expensive than the FP because of the blade changing mechanism in the hub and the sensing devices and controls on the engine.

    So if the boat operates at only very high speeds there is no point in having CP as the proposed operating band is tight and inside the design band.

    If the boat operates at only two speeds the propeller is usually a compromise based on the operating profile. If it is high speed 2/3 of the time then the propeller design would be biased towards high speed, in the long run it gives the lowest operating cost taking into account fuel costs, repairs/maintenance and so on.

    The Kt-Kq diagram may be used to review the whole operating regime. There are many references to Bp~Delta diagrams but these are the handiest for the design condition but not so good for the others and useless for the Bollard Condition – what is the “pull” when the boat is stopped, hence the name. It was tested simply by tying up a line to a bollard with a dynamometer or load cell in the line to measure the pull. In the Bp~Delta diagram. Bp = N*P^(1/2)/Va(2 ½) and Delta is N*D/Va where N = rpm, P = power, Va = propeller speed of advance. As V is zero the terms equal infinity and so the diagram cannot be used for the bollard condition. The Mu~Sigma diagram is essentially tailor-made for the bollard condition.

    So a tug is a good vessel to explain what happens outside of the design range. A tug has three basic operating conditions;
    • Pushing a massive ship towards the quay and the wind is blowing the ship away from the dock and going nowhere – the Bollard Condition
    • Towing something and actually moving at some obvious speed – Towing Condition
    • Racing to get somewhere, perhaps a ship in distress and it’s an emergency – Free Running Condition.
    So what do you design it for? I will deliberately keep it simple and neglect any constraints such as sea-keeping, rolling in waves, weather etc. I will also skip the analysis of operations and make simple, easy to understand comparisons.

    The design condition should be the second one – Towing. The only thing to specify would be a tug speed, full power would be absorbed at that speed. So if you tow big things you would have a slow speed, small things at a faster speed so pick a number. That would depend on what the traffic is in your area but the usual is to specify about half the free-running speed. I’ll only cover a diesel-driven, fixed blade propeller.

    Now here’s the rub. At the bollard condition you have a torque overload, you aren’t moving and the propeller is trying to draw more power but the revs are dropping because it can’t absorb it, fuel is still being injected for high power but the turbo-blower is linked to the engine and there isn’t enough air to burn the damn stuff. Hence the dense black smoke.

    In or very close to the Towing Condition everything balances, power, revs, speed, thrust – the whole nine yards.

    Now Free-Running, this is just the tug, nothing under tow and Full Ahead. The propeller is under-loaded but it tries to draw more but there’s no load so it turns faster trying to put more rpm with the max torque. Now we have the engine racing and we still don’t have full power – your manual shift car in bottom gear and your foot on the gas pedal.

    Better engine control systems and much more effective turbo-blowers reduce what I have described but they cannot solve the problems – you can break any law you want and get away with it except those of Mother Nature.

    On a typical tug the revs would fall about 10% at the bollard condition and you would get a pull of around 28# per hp for something designed for the Towing condition described above and it would fall to about 22# per hp for something designed for a faster speed.

    This can be improved by fitting a Kort nozzle – named after it’s “inventor”, the German Dr. Kort. Typically a tug would have a 4 bladed propeller with a pitch ratio of about 0.7, a bit less if a high free running speed was not needed and a bit more if it was important. So a “normal” propeller would give us a thrust factor of about 610 (applied to a complicated formula) but using a Kaplan propeller in a nozzle would give us over 800, better than a 30% increase but we would not go as fast! A Kaplan propeller – say you took a 5 foot diameter propeller to fit a 4 foot nozzle, you would cut the tips away and you would have a home-made “almost Kaplan.”

    If you fitted a CP propeller in a nozzle you’d have a 20% increase or more and you would also go faster, about one knot, because you have changed the pitch ratio from around 0.7 or 0.8 to 1 or 1.1 or so. At the other end the pitch ratio fell to 0.6 or less, the revs were maintained and so the thrust increased.

    In the free-running mode without a nozzle the engines are over speeding so the revs are pinned to some maximum value at a lower torque and you go as fast as you can but only use about 2/3 of the power. A nozzle with a fixed blade propeller causes more drag so there is no point in that but the CP screw will adjust so the nozzle will not help go faster even though it improves the bollard pull.

    The rule of thumb for a nozzle was to fit one if the Bp coefficient was greater than about 45, see the formula above with all units in imperial measures. Say the propeller turned at 200 rpm, the power was 2,000 hp and the speed of advance was 10 knots we would have a Bp of only 28.3 – no nozzle. But if we increased the revs to about 1,000 it would seem a nozzle would help. The problem again is that the propeller would need a total redesign and the efficiency would drop off but the nozzle would help and we’d be back to square one - except the propeller is quite different so don’t just stick a nozzle on and hope for the best.

    There are other things that help –a variable speed gearbox that can improve design characteristics so helping to give a better operating design range.

    A Father-Son arrangement that is common on fishing boats. For example, a deep sea trawler has to be fast to get to the fishing grounds and then slowly drag this huge bag behind it trapping fish then race home again. So it is common to fit two engines, one gear-box and one shaft/propeller. The father is the big engine and the son is the smaller one usually about 50 or 60% of the power of its dad. So you have three choices Father, Son or Holy Ghost

    Two things have really puzzled me over the years
    • Why CP propellers were only for ships – now it is encouraging to see that they are beginning to make inroads.
    • Why people did not have a better way of selecting a propeller.
    These two images may make you salivate. They are scanned images of a pair of calculators made and given away(?) by Caterpillar. I inherited them from a colleague who retired years ago and he was given them by a Cat rep. who regularly visited the yard. I have no idea if they are still available but I doubt it.

    Both scales show on an image, not back and front of one scale on an image. Other than the names only the Propeller Calculator has any identification. Look at the Analysis Chart and then across to the lower left and you see © 1961, Caterpillar Tractor Co.( which is on both slides) and Form No. 40-20428. I’ve lost track of the number of people who have asked me to help with their propellers and general things about speed and power. These slide rule calculators were a God-send

    [​IMG]
    [​IMG]

    The propeller chart might help you, although it has Bp on the bottom scale it does not use Delta but you still get a good idea of what goes on (for the screw type as noted on the extreme upper far left). The chart should settle any arguments about 85% propeller efficiency – it is possible, of course, but you would be trying to fit a propeller bigger than an ocean liner on a runabout.

    The term Va is needed for Bp, Delta and also the thrust formula on the prop chart. As a vessel moves through the water under the action of a propeller some water moves with it so that the speed of the vessel through the water is greater than the speed of the propeller through the water. This is the effect of the wake and Va = V*(1 – Wt) where V is the boat speed and Wt is the Taylor wake factor. Be careful if you see any references to the Froude wake factor, it is quite different and not the same at all – avoid it.

    Unfortunately I can’t help you with wake factors. They depend on all kinds of things relating to the vessel and the propeller so you have the situation where the vessel could be increased in size with all dimensions in proportion – 10 times longer, 10 times wider, 10 times the draft but the same shape, for example, but the propeller changes in a different way so the wake factors change. All my technical books are about ships so the factors are quite different to those for small boats and the like –sorry. There must be a site that shows small craft wake factors.

    I hope this has helped, I have tried to simplify things to get the point across so a professional designer or nav arch may disagree on some points but it would be minor.


    To be contd – drive systems and losses in efficiency
    Michael
     
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