Messages are listed in reverse order by date posted.
| Files From: ed Email: ebel440@hotmail.com Category: Materials Date: 24 Dec 2003 Comments: does anyone have any cad/cam files or plans for blades I can't seem to find any with sizes I am looking to make a 24 disk 4.75" turbine |
| Basic knowledge needed please! From: Sean Momsen Email: Numba1stunna_420@hotmail.com Category: Applications Date: 18 Dec 2003 Comments: Ok so i get the general idea of adhesion and how air turns the set of disks but what is all this talk about combustion and fuel jets and used petroleum? can someone please explain. Also I don't know if this has been discussed before but why not make a exhaust housing side (side where the disks are. connected to a conventional compressor turbine housing on the other side and use it as a "Telsa turbo"? the only thing wrong with that I can foresee is all of these models we are building don't spin fast enough. The average turbo charger at full boost spools to 100,000-150,000 RPM <---or so I have been told. The other thing I was reading on here was talking about thermodynamics. Being only a senior in high school I am not too familiar with this and would like to know what would happen if connected to the exhaust manifold of a engine if the heat of 1250°F would change spool up? Talking about pressure. most models have their compressor set to like 150psi or something like that how many CFM (cubic feet per minute) of air is this? I was just thinking exhaust flow from an engine is not really measured in psi but in CFM. Sorry for all the basic questions but i am very intrigued by this and everyone had to start somewhere on learning about the Telsa turbine. thank you for your help. Sean Re: Basic knowledge needed please! Comments: Actually, It should work. It it might even be better that a standard turbo. This turbine doesn't need to spin as fast as standard turbines to put out equal energy. Since it runs slower, it should in turn, last longer too. Good luck. Re: Basic knowledge needed please! Comments: so are you suggesting that we put a Tesla turbine on each side? one acting as a pump (sucking the air in and forcing it into the intake manifold) and one fed by the exhaust driving the shaft, turning the pump? I was suggesting just having one Tesla turbine on the exhaust side to turn the shaft because it is more efficient that a turbine with blades. and having an actual compressor turbine on the other side compressing the air that way into the intake manifold. which one would be better? would rotation mater on the compressor side to suck in the air if we used the 2 Tesla design? Re: Basic knowledge needed please! Comments: I guess you can experiment around, I don't actually know. Re: Basic knowledge needed please! Comments: I've had to sign non-disclosure forms before, I'm sure I'm not the first or will be the last. My point--don't be suprized if people don't want to post their latest innovation to the Tesla disk engine. Some people can't for legal reasons. The question is are people *reading* the posts. I think more are than you know, just waiting to steal a good idea. Others don't want to share--can you blame them? Look at how Tesla himself was ripped off by Westinghouse! I can tell you this--Tesla engines work, there are some ones being used you'll never hear about. I may or may not have seen them ;-) Keep the forum going! Re: Basic knowledge needed please! Comments: I STILL NEED HELP!!! PLEASE read my original post and help me with the basic knowledge. thanks Sean Re: Basic knowledge needed please! Comments: I know that this post is old, but in case there is somebody who needs this information, I'll give what I have. I have been experimenting with pumps. I have been unable to find any good information about them, but it seems that instead of increased efficiency when the discs are closer together like in the turbine, the discs must be placed farther apart. I haven't figured out exactly what spacing is best for pumping air. I need to set up a quick and dirty method for changing the spacing without having to rebuild the case every time. Anyway, since you only need about 8 psi without rebuilding your motor, you could do it easily with a Tesla pump, but you do need to make sure it doesn't pump too much air under all conditions. I think that strict focus on the turbine and not the pump is an error. Conventional turbines are not generally run on combustibles without a compression of air. A Tesla turbine and pump combination is the most promising method for using it as a power production system. The final word is, in order to find out what you need to know you need to experiment yourself. Either nobody experiments with pumps or they don't want to share their information. Good luck. |
| efficiency From: Corbin Irvin Email: Cajunjoe_here@yahoo.com Category: Efficiency Date: 13 Dec 2003 Comments: How much air do they use compared to standard vaned turbines? Are they more efficient than vaned turbines and if they are, how!?!? |
| Simple questions From: Corbin Irvin Email: Cajunjoe_here@yahoo.com Category: Materials Date: 10 Dec 2003 Comments: Hi. I was wondering, does the turbine disk have to be completely flat? for experiment purposes can it be a cardboard disk? Is there a special kind of injector needed, or can I just blow across it with a blowgun? I hope to turn this device into a really awesome Gas turbojet for a go kart, and maybe a car! Does anyone have any power curve data or anything like that? Re: Simple questions Comments: In response to your question, from the different designs I have tried, you shouldn't have too much of a problem with cardboard. For my first TT I used business card paper, printed out 4 disks per standard sheet (with a nifty little radiation design on it to cut out). In total I used 8 disks, with business card washers cut out (actually just little squares, lazy I know...) then glued to the disks with glue sticks. For the casing I used the lid from a tobacco tin (plastic, players 95% more fits nicely). I cut a slot in the side of the lid to input the air, the glue gunned a straw at (as close as I could get anyways) to 90 deg to the blades. I then cut another piece of BC paper for the other side, with the radiation design in it. Then electrical taped this to the lid. I don't have an air compressor or tank so I just blew into it to start with, I was very surprised at how fast it spun. I took a bellows for inflating air mattresses and hooked it up to the straw, WEE!!! Away it goes! So I took a little DC motor I had from an old VCR and stuck this where the nail was (The shaft). I was able to get about 6V (AC on the multimeter) out of it with the bellows pumping it. Enough to light an LED as well. When I hooked up a 9V battery to the motor, I could actually blow bubbles in water with the straw aprox 3/4" deep in the water. Now onto my questions <grin>, has anybody experimented with the size/shape of the exhaust outlet? When I had the turbine set up as a pump, I had greater pressure coming out when I cover about 1/3 of the holes, but when it was set as motor, it worked better with holes the same size as in the discs. I'm not quite sure why this is and would appreciate input. Also is there a calculatable optimal output size/shape? I am just starting with this, I have lots of tools and scraps at my disposal, but by trade I am an electrical engineer, not mechanical. I found this page in the process of building a vandegraff generator and tesla coil. For cooling the turbine, has anyone tried thermoelectrics? I think this combined with magnets and coils in the discs might make for an optimal power source. Any ideas? Re: Simple questions Comments: Just a couple more ideas as well, has anyone tried magnetic bearings? They could be powered using thermoelectrics maybe? For smaller test TT you can salvage magnetic bearings for newer scrap VCR's, they come with the Hall Effect sensors and the controller IC right on the board. And one more question to go along, has anybody thought of how a TT would have to be designed in order to fill a compressor tank (dimensions, # of disks, etc)? Or does it even yield a great enough pressure? Hopefully I should be able to figure these out for myself, but it would save time/energy if someone has already tried it. I plan on doing different experiments myself on different designs and posting them here along with pictures maybe if anyone's interested. I really liked the AOL CD TT so that is my next project. So far I have the disks set up, but I have noticed that if there is a gap between the disks and the covers for the TT the efficiency goes way down, not sure if it's the same with the pump part yet tho. The hardest part I've found with building these so far seems to be the cases and minimizing the gaps to the disks, (should there be some gap between the edges and the top?) Just one more thing I like about this web page, and I live by the motto "If you know, tell. If you don't, ask." I think the world would be a better place if knowledge was free. |
| Disc spacing From: Rob -- airpiraterob@hotmail.com Category: Theory Date: 15 Oct 2003 Time: 13:55:53 Comments: I remember reading at one point that the boundary layer thickness is only so much and the disc spacing should not exceed that total boundary layer of both disc surfaces...(1/16th" and 1/16" from both discs means a spacing of 1/8" inch) how does this boundary layer change with disc size or is it a standard thickness all around? Re: Disc spacing Comments: In some of the calculations that I've seen the boundary layer using steam or compressed air was around .002-.008" for each side. |
| Small Turbine Project From: Mike K -- ame2000@lycos.com Category: Member project Date: 15 Oct 2003 Time: 13:43:16 Comments: I am considering a small, wood-fired, Tesla pure steam turbine to power a permanent magnet alternator. I have 100 1/2" diam. neodymium disc magnets for my alternator and I was wondering how many and what diameter turbine disks I should use to spin them around. I was also wondering what the usual intake/exhaust area ratio was for Tesla turbines. As I will be building this largely by hand I would like to keep the parts count to a minimum. I measured the flame temp of a hardwood fire and it was about 700 deg Celsius. I can hardly wait to get started on this exciting new project! |
| Tesla Turbine From: Denis Carrier Category: Theory Date: 15 Oct 2003 Time: 14:14:21 Comments: I have just finished reading "Tesla's Engine" by Jeffery A. Hayes and would have 3 questions: Question 1 - On page 49, it is said that the Tesla turbine can do without a condenser (when used as a prime mover associated with steam). No technical details are given such as: - at what speed-diameter combination this condensation happens - at what supplied pressure and temperature; using latent heat of saturated steam or from superheated steam. Question 2 - Starting from rest to maximum speed, does someone ever graphed the curve of efficiency compared to the ideal Carnot heat engine for various diameters and rpm? Question 3 - When the fluid adheres to the surfaces of the disks by capillarity, it looses some of its heat. Are there any studies about that heat exchange at least on the theoretical level? Best regards. Denis Carrier - denis.carrier2@sympatico.ca Re: Tesla Turbine Comments: 'Not smart enough or have enough real experience with these to know all the answers to your questions, but on the condenser subject, it is my understanding that there is supposed to be a huge temperature/pressure drop of the fluid running through the turbine and that this provides for a lot of the steam returning to it's liquid state. |
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From: crowland@citywestwater.com.au Category: Combustion Date: 04 Sep 2003 Comments: I am looking for advise on the most efficient configuration for a gasoline/atmosphere combustion chamber suitable for mounting on a Tesla Turbine I plan to build during my Christmas holidays. The Turbine will be (subject to redesign, which happens often) a eight live disk, 200mm (just under 8 inches), simple gasoline fed engine. Some advise on chamber sizes and shapes would be helpful. Also any ideas on delivering the fuel without combustion gases escaping back up the fuel or air inlets. I am aware of Tesla's "valvular" inlets but I am hoping for a more practical (smaller, off the shelf?) solution...some sort of check valve perhaps. Is it likely that a gasoline powered turbine of the above proposed dimensions will be capable of a start from stationary using only the combustion chamber gasses? ie without compressed air or other mechanical starter. Will a ventilator at the exhaust port be required or recommended? I have my own ideas on all of the above but they are just that...ideas, nothing proven....yet. Re: Gasoline combustion chamber From: Dick Eagleson Email: duheagle@yahoo.com Category: Combustion Date: 13 Aug 2004 Comments: Google the search term "sonic choke" and I think you'll find what you need. Re: Gasoline combustion chamber From: Adam Sacks Email: itchychicken@email.com Category: Combustion Date: 19 Nov 2003 Comments: I have been thinking of using a ventilator on the exhaust as well and was wondering if you had run across any data on the effects of this on regular turbines. The effects I think would occur would be that you could run the turbine at a lower temperature or same temp. at a slightly higher compression ratio, for a better power to weight ratio. Re: Gasoline combustion chamber From: Corbin Irvin Email: Cajunjoe_here@yahoo.com Category: Combustion Date: 11 Dec 2003 Comments: You could build it like a gas turbine engine. www.junkyardjet.com Just substitute the Tesla turbine for the turbocharger.
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06/01/03 James C. Morris Subject: RE: Richard Gideon report on nozzles This is a response to Rich Gideon's report about trying my suggestion for
optimizing the turbine inlet nozzle by measuring the outlet temperature. For those who missed his report, nozzles refined this way
more than tripled the output rpm of his turbine. James C. Morris, P. E. (Ohio, retired) |
| A: Excellent explanation of thermodynamics principles. -- Ken |
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05/30/03 John Mahler Hi Ken, Thank you for replying to my comments. I am currently building a steam turbine with 6" disks, my largest to date. I will take your excellent suggestions on materials and roughing/finishing out the parts. The curious thing to my thinking is that, though most of the input energy leaves the turbine in the form of torque/work, there is no heat build up in the disks which would lead to several kinds of heat related failure. In conventional bladed turbines, heat does build up and requires very high alloy blades not to mention oil cooling. I do anticipate the day hydrogen will power everything, obviating the use of mineral fuels and their pollution. I only really mentioned steam because it is easy and lets the user choose which fuels he uses to power his energy conversion device. I covered the energy crunch of the 1970's previously. But some people live where the sun is not a reliable choice, where fuel is expensive, where they may have abundant fuel in the form of crop residue, brush or woods needing clearing. So, a steam plant is really the energy independent choice. However, I am not, in any way, choosing to close the door on any alternative energy source. I have even heard of spent nuclear fuel, not weapons grade nor good enough to use in regeneration of fuel rods, being bound in quartz glass. The material remains thermally hot (glowing dull red) for a half life of 200 years. I think this is on the Adams Atomic Engines Inc. http://ans.neep.wisc.edu/~ans/point_source/AEI/AEI_home.html This is an interesting site if you have never visited it. I realize everyone has their own particular alternative energy source. I have friends in several heat engine disciplines who maintain "only" their chosen source will dominate world wide markets. I even fall prey to such thinking. My favorite energy is solar. I would love to see the day when heliostats track the sun with solar heated boilers, driving steam engines to make electricity, dehumidify the air, yielding water in arid places, and refining hydrogen and oxygen from the air by the Linde process. I once dreamed of wind farms in the early 1950's when it was all the rage to expect nuclear power to dominate the energy landscape. Today, we have wind farms and our race is beginning to utilize the abundant energy of the sun, hitherto only used to drive our atmosphere's hydrologic cycle and grow crops. I speculated then, wind farms made more sense than nuclear energy because it was free, had no radiation hazard, and could exploit arid lands not fit for growing crops. I was also a great admirer of wave technology and trying to exploit the oceans for minerals, growing food and making energy from plankton, or other life forms abundant there. Today, only wind farming has been realized to a limited extent. In talking with Adams, I realize why these dreams have been so long delayed. It is the business interest in conventional petroleum resources that occupies the imaginations of mankind. Until we can persuade the majority of American consumers that energy should be affordable, clean, environmentally safe, abundant and inexhaustible, our dreams are likely to be delayed. I hope I have said nothing in my comments previously, nor here that offends. I do not mean to offend by any of my comments. I do see a bright future for our country and this generation if war can be avoided with a world knowing no other way to change the course of mankind's history. I am convinced that war and its industry is the path of extinction to the human race. If war can be avoided, there is a bright future for the human race. |
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05/22/03 Jeremy subject: Crank Throw Does anyone have any AutoCAD drawings of a crank shaft and crank throw either for a single cylinder engine or an inline six sylinder engine. size is not important |
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05/21/03 Nelson subject: TT plans Hello , my name is Nelson, I'm engineer and live in Brasil - South America. I think that is fantastic this technology. I'm new on club. I'm thinking to build a little Tesla turbine and want to know if somebody has some plans to make this. I have a lathe and a Roland 3D mill. |
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05/12/03 DC Risley Subject: rock on When I came across the turbine builders club site I got chills. "This is it!" I thought. You are hitting it dead on the head! The only way to topple the monopoly of big biz is to put the info into the hands of the little-guy tinkerers and allow them all to share their results so that the product can evolve. This is the only site I've seen that is realistically achieving the goal of low-cost energy. You can count on my input in the near future. |
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05/10/03 A. Brady subject: Valvular conduits I am considering experimenting with valvular conduits when I get my basic turbine built. Looking through Tesla's valvular conduit patent application it seems as if you need a defined period between combustion pulses to re-charge the combustion chamber. This is achieved with a slight vacuum generated by the spinning runners. I have gathered that better valvular action is obtained with smaller cross sections 20-40 square mm. So to get enough mass flow you would use multiple combustors around the circumference. The next problem then is would you get too much interaction between the combustion pulses. upstream pulses would cancel the induction vacuum of downstream induction phase. Back to the turbine. A lot of discussion of star spacer geometry and effects. a lot of good results with small winglets included. my view is that with the appreciable amount of structural cross section the winglets and spacers combined create, why not negate the center section of the runners completely. the inside runner disc will be in the order of 6mm thick and the entire disc pack will be supported from it. there will be no center shaft through the disc pack itself. give me a blast if you think its crazy but I'm going to try anyway. |
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04/17/03 Kurt subject: MW-class TT Turbines How far away are we from developing MW-class tesla turbines. The conventional turbine manufacturers cannot meet demand so there is definitely an enormous market for an easy to make turbine. |
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04/15/03 Steve Redmond Subject: New disk turbine completed Hi Ken. Thanks for our prior discussions, your general encouragement to us all, and your open approach. After threatening to do it, I've just completed a new disk turbine from castings, and it's up and running. I'm posting the progress on my website as I go along. The website address is www.SRedmond.com . |
| A: Thanks for the update on your progress. Encouragement is a 2-way street, and we appreciate your work and progress reports as much as you appreciate ours. -- Ken |
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04/12/03 David Butcher Subject: Efficiencies & RPM's On page: ptbc20a.htm the chart shows rpm's flattening out at 3000+, while you suggest that the max speed for this turbine would be 35,000 rpm! Tesla ran his turbines at 125 PSI -- not that much higher than the test unit. How would the RPM's of the test unit ever reach such a high value, which is ten times the speed at 75 PSI? |
| A: Since the turbine is running at such a low rpm, centrifugal backpressure is very low, which results in low efficiencies. As the turbine spools up to around 50% of its maximum rpm, backpressure increases dramatically leading to a rapid rise in efficient conversion of kinetic energy to shaft power. -- Ken |
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04/09/03 John Mahler I have built 4 experimental Tesla turbines. I once belonged to TEBA, but found them didactic, reactionary and very idiomatic, harking toward worship of technology and inventor which precluded advancement of the art. Only one of my turbines failed. It was exposed to too much input energy, 60psig. steam and was torsioned to failure. The disks literally ripped themselves off of the output shaft. Three of my turbines are still working. All of them are 2.5" to 3" in diameter. One is for air only as it is constructed with epoxy glue and cannot sustain much heat. The 3" turbine currently has bad bearings. I used it with steam once and melted out the grease in the bearings. The lab seals do not do an adequate job of stopping the steam. When I replace the bearings, I will also redesign the seals. I will use ring lab seals on the shaft and quenching water bath with conventional ceramic carbon water pump seals. Water will run through the seals at all times. I admire the progress you all have made in the advancement of this technology and applaud you all. I personally think this turbine would work best with steam. I have had good results with this energy source, but the hardware was inadequate to stand the forces. Every one of my previous experiments has taught me what is needed to build a better turbine. I am currently working on a 5" turbine. In the manufacture of its parts, I learned a great deal which will make the next one much easier to construct. For instance, I turned each disk on my lathe because I did not know about plasma torch cutting methods. I just discovered this technology from a friend at work who is a welder. He can cut any size disk I require. One of the reasons I like steam power is that it is truly a multi-fuel method of converting fuel to kinetic heat energy. Most of the present internal combustion type turbines use gaseous or liquid fuel which ties them to petroleum dependency. Please do not take this remark as negatively intended. I went through the Carter Gas Crunch and spent far too many hours in gas lines on my lottery day, still refused when I got to the pump. I would like to become a member of your organization and have enjoyed your page very much to date. |
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A: We agree that steam will always be a viable means of powering the
Tesla turbine – especially in the area of free energy (solar and
geothermal). As we move towards a hydrogen infrastructure, direct
combustion in properly designed boundary layer turbines will eventually
beat out piston and fuel cell systems.
On another note – what material are you using for your rotors? If you use 0.032" stainless steel they will withstand the centrifugal force without shearing. One last suggestion – plasma cutting is O.K. for cutting rough blanks, but you will still have to post-finish the parts on your lathe. -- Ken |
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03/06/03 Jiun Horng,Teoh Subject: Steam car turbine If I want to design a steam turbine which will operate in a steam car that will run at 200mph top speed, how many rotor I should use approximately. |
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03/03/03 abn email: abnengineering@cs.com subject: Are Tesla turbines self correcting for load? "The machine will, generally, perform its maximum work when the effective speed of the runner is one-half of that of the fluid; but to attain the highest economy, the relative speed or slip, for any given performance should be as small as possible."... So does that means that as load is increased and rotor speed decreases, that torque increases and in a sense the turbine will attempt to self correct itself rather than stall? Of course if the load drops the rotor speed below 50% gas speed, then torque starts to fall and the rotor will stall if no one "gives it more gas". |
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03/01/03 P. Childs email: audiosoundanddesign@yahoo.com subject: materials I found your site not long ago and I am fascinated with this. I have a question on materials though. I only plan on a small test model for now and was wondering what kind of performance I could get out of hard drive platters. I’m not sure what kind of metal they are made of , but they are already polished and balanced. This seems like an inexpensive starter kit. Do you know of any drawbacks to this idea? Also, if I use these, would I still need to run bolts through them at 30 degree increments? How about the center, how many bolts need to be there? I'm very new to this but am excited at the possibilities. thanks for your input. |
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02/28/03 yreglero email: yreglero@yahoo.es location: Uk Hi everybody , I am a mechanical engineering student in the UK and I am looking for a blade disk diagram for my final year project. The aim of my project is to simulate in Finite elements ANSYS PROGRAM the vibrations of those blades. If anybody has something related to this question please send me any information to this email: yreglero@yahoo.es |
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02/17/03 Ben Lipkowitz Subject: PTBC pulse combustion article I never understood why many Tesla experimenters used pulse combustion - it >The results, compared to continuous burn, are: more of the potential |
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A: All of the experimenters using continuous burn systems have failed
to arrive at self-sustained rotation (with the Tesla turbine). Tesla, in
the early 1900's, achieved self sustainment using a pulse combustor and
his aerodynamic valves – at a claimed 60% efficiency.
On the question of increased temperature resulting in higher efficiencies, it isn’t necessarily so. The law of thermodynamics says that energy flows from a hot region to a cold region. It is the flow of energy that produces work. The reason conventional turbines are so inefficient is due to the amount of energy pumped back into the compressor stage. Combustion in the turbine increases the volume and flow rate of the compressed air – which is turned into work by the rotor. Conventional turbines gain efficiency by greatly increasing the volume and velocity of the compressed air. The Tesla turbine gains efficiency only when its rotating rotor speed approaches the working fluid velocity. Simply dumping large amounts of fuel and air into a combustion chamber does not increase efficiency of boundary-layer turbines. Fuel and air must work together to accelerate the air and combusted products to as high a velocity as possible to achieve efficiency. Since a high degree of air compression wastes horsepower, any combustion model that lowers the need for high compression automatically results in higher efficiencies – thus the pulse combustion model. With pulse combustion, a greater percentage of fuel and air is transformed into highly accelerated gas, less heat is uselessly transferred through the combustion chamber walls. -- Ken |
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02/15/03 Jeff P email: jpflug@charter.net subject: machining Hello, Just happened by your page and it caught my eye. I am Journeyman Toolmaker and I have a few machines in a small shop. You have a very informative web site. I am interested in helping design and manufacture prototypes for inventors especially in the renewable energy field . I have a web site that shows the shop and has a few part samples that have been done in the past. www.geocities.com/promachine02 |
| See our PTBC Resources page! |
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02/14/03 Simon O'Farrell Subject: A couple of questions Hi, My name is Simon O’Farrell and I have read you entire site with
fascination. I do have a few of questions and I am hoping you can shed some
light on them: |
| A: Tesla designed both water pumps and air compressors using boundary-layer disk principles. The fluid moves from the center of the disk pack outward. A volute casing transforms the high velocity fluid to a pressurized fluid due to the diffuser action of the volute housing. Efficiencies are relative to the application, but generally it can be said that radial compressors are more efficient in low volume, high pressure (or velocity) situations – especially when several stages are used. -- Ken |
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02/10/03 Hamish Edgar Subject: Hi from Hamish ... Your site mentions that people have been trying to get in contact with me, I can be emailed at h.edgar@irl.cri.nz -- Regards, Hamish Edgar |
| Good to hear from you! We look forward to more engineering analyses, tips & ideas for improving on Tesla's work. -- Pam |
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01/27/03 J Davis Subject: Job market? What is the job market like at this time & is anyone hiring on 22 Yrs of experience? Plus a degree in mold making. |
| A: Job market is lousy due to political incompetence in high places. We'll keep you in mind if a job opportunity arises, in the meantime we'll post your message to the Forum. -- Ken |
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01/27/03 Joe Dupont Subject: fascinating.. why not run this to an exhaust of a car engine as a muffler and generate a hell of alot of electricity.. |
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01/26/03 Robert Miles subject: Boundary layer turbines I am qualified to butt into an Arizona organization only by virtue of the fact that I hunted javelina in the desert near the So. Cal border...long time ago. Grrrreat country...coming back some day. I'm now in the frozen Northeast and wonder if there are any TT enthusiasts in this area with whom I might get together to discuss the fabrication of a propane fired turbine to marry up with a speed reducer and alternator for emergency power applications. Or, perhaps you have an idea or two that we might explore...? I have recently completed a contract with Bechtel/US Air Force to do some groundwater remediation work at a superfund site nearby and I can also envision a Tesla pump application in that line of work |
| A: Presently nobody has a direct combustion system operating on propane – steam systems are only about 12-13% efficient so a free source of energy such as solar or recycled oil is the only cost effective approach. Are you looking for technology for personal use, or to start a small business? This year we are working on a waste oil system for residential cogeneration use. Check out our Special Programs on our PNGinc site. -- Ken |
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01/26/03 Chuck Johnson Subject: TO Richard Gideon (Turbine improvements) Richard, Years ago, I invented (on paper only) a gas turbine design consisting of two stages. These two stages work in cooperation to produce output energy. The two stages are located close to each other, both within the same pressurized enclosure. The first stage consists of the invention of Hero of Alexandria (first century B.C.) . This would be a hollow rotor six inches in diameter. Pressurized gas would be introduced near the center of rotation by means of a rotary coupling. The gas would travel to the outer rim of the rotor, and then be emitted by a series of nozzles. The nozzles would be directed tangentially, and would cause the rotor to rotate in a clockwise direction. The emitted gas would have plenty of kinetic energy left over, and this gas would be rotating in a counterclockwise direction. The nozzles would be tilted slightly so as to direct the emitted gas across to the intake channel of the second stage rotor. The second stage rotor (also six inches in diameter) would be the device invented by Nikola Tesla and Richard Gideon. A rim or channel along the outer edge of this rotor would help to capture the gas stream efficiently. As the energetic rotating gas moves towards the center of rotation, it transfers its kinetic energy to the rotor. The second stage rotor rotates in a counterclockwise direction. The two stages of the turbine rotate in opposite directions at equal velocities. Each stage puts out the same amount of energy. Each stage is connected to an electric alternator. The alternators are under the control of an electronic system that makes sure that equal rotational velocity is maintained. The electronic control systems monitor the gas pressure, and by this measurement, the gas ejection velocity at the nozzles can be calculated. The electronic control systems then cause the two rotors to have a rotational of exactly one half of the gas ejection velocity. The pressurized gases are thereby converted very efficiently first into mechanical output, and then into electrical output.
The first jet engine
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01/26/03 Chuck Johnson Subject: TO Richard Gideon (Turbine improvements) Richard, To make the best possible turbine, we must design for a durable, compact, lightweight turbine that is efficient and powerful. Last year I was thinking about power, torque, RPM, and efficiency, when I emailed a question to Ken Rieli. -- It seems that we can increase the power output of a turbine when we increase the temperature and pressure of the gases. -- It seems that we can increase the efficiency of a turbine when we have the outer edge of the rotor moving at the same speed as the stream of moving gases. --It seems that your recent experiments point towards rotors that are efficient in converting the energy of a gas stream into horsepower at the output shaft. |
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01/26/03 Chuck Johnson Subject: TO Richard Gideon (Turbine improvements) Richard, Greetings from Pennsylvania. I just read your December 5 posting and I would like to ask you this: your text mentions blades as spacers. There are no pictures in your posting. Are the blades of the experiment the "simple blades, like the paddles on an old sternwheeler steamboat" that you describe near the beginning of the article? --- This is an idea that I had years ago, that straight blades should be provided that point towards the center of rotation, arranged like the cuts in a pizza pie. With such an arrangement, the swirling gases can't exit the turbine until they have given up most of their kinetic energy to the rotor. |
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01/26/03 Scott Beach Subject: TO: Richard Gideon (continued from 01/20/03) Richard: Yes, cutting all of those angled teeth would be time-consuming. Here is an idea that might reduce blow-by and also reduce manufacturing time. Imagine a disc pack that has outer discs that are 6 inches in diameter while the inner discs are only 4 inches in diameter. Winglets span the distance between the outer discs. The outer edge of each of the inner discs is sharpened to a knife edge (a very quick and easy machining operation). These sharp edges should reduce the extent to which working fluid bounces off of the outer surfaces of the inner discs. The knife-edges on adjacent discs would form a V-shaped nozzle that compresses the working fluid and forces it down between the discs. I have suggested to Mr. Rieli that he build Tesla turbines of titanium. Titanium has a higher melting temperature than steel and only 55 percent of the weight. A titanium turbine could operate at a higher temperature (more power and less pollution) and its lower weight would be advantageous in applications where the turbine is in a moving vehicle. Titanium has very low thermal conductivity. If you try to machine it, use high feed rates and low speeds. Otherwise, the work will heat up rapidly and melt your tool steel. |
| A: Titanium is definitely a material we are interested in for lightweight aircraft applications – where higher costs are justified. For all other applications such as electrical power generation, land vehicles and marine, either 4140 or 316 steel will work just fine. -- Ken |
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01/25/03 name: Brad Stanford email: brad@bradstanford.com subject: Turbine pictures have moved For those of you looking for my turbine pictures, I recently changed my web page layout. They're now at http://www.bradstanford.com/Pages/Flying%20Alternative.html I've started a new section on alternative propulsion as it applies to flight. The Tesla Turbine is my first (and currently very short) installment. The turbine is still for sale, but I don't actually state that on the page. I'm considering putting it up on ebay, since I don't have the time to work on it any more. It is a working model with labyrinth end seals, and it will run off of compressed air, the water hose, or a yard blower. Not a lot of torque, just proof of concept. For those of you who have already visited and emailed, thanks, and glad to meet you! |
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01/24/03 name: Gordon Henry email: gordonh@lakedalelink.net subject: shape of outer disk edges ???? I have read through this GREAT site cover to cover as it were, and have a few questions and comments. First I know that there is no way for us to know what is going to work best without building and experimenting with it, But as stated else where I don't want to re invent the wheel ether. Q? Has anyone done work with different shaped disk edges, ie, square ] ,round ) , or tapered > . I am wondering what effect these different shaped edges would have on the working fluid/gas as it enters the disk pack. Other than the saw toothed idea I haven't seen anything here. It seems to me that the pointed with slight rounding at the transition to the disks working surface would help reduce turbulence in the disk pack and speed up the formation of the laminar flow effect ( closer to the edge of the disk ). Also your articles on the air foil shaped spacer's give one alot to think about. The one you show resembles a wing cross section of an old airplane,( though exaggerated) it would provide high lift but also high drag. which would or should create alot of turbulence. In the case of the turbine this shape would also seem to force the working fluid to the center and out of the turbine faster. Wouldn't that bring down the efficiency? Somebody asked about using a supersonic airfoil, from what I have read these will produce less lift and drag, depending on the angle of attack to the flow of the working fluid of coarse. We must also consider the fact that these airfoils will be working opposite to a wing in that they will start with a high flow rate over them and when the turbine is up to speed the flow rate around the air foils would be at a virtual stand still (when running no load). Just had another thought to see the flow path/turbulence has anyone tried making a turbine using Plexiglas (2 disk), compressed air and a thin stream of smoke injected at the edge of the disk, and a strobe light (for stop action) to see what is actually going on in the disk pack with the different air foils and star washers etc. Also thinking about how to make the air foils rotate in the disk pack. As stationary foils will most likely require a compromise between start up torque and top end performance. If they could be spring loaded for max angle of attack at start up and pulled ( centrificaly ) to parallel with the in coming flow to reduce turbulence, and prematurely forcing the working fluid out of the turbine. I would like to know what you think or know about these thoughts. Thank You for your web site and time to respond to this. |
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A: I can tell by your questions that you have spent some time studying
aerodynamics and how these principles might be applied to the Tesla turbine.
First of all there is no experimental data on the relationship of disk leading edge shape and efficiency. This would be a good area of study for someone like yourself. The winglet shape we used is a combination of a traditional airplane wing profile and a bladed turbine hot section profile. There remains a lot of work in this area to finalize the entire dynamic spectrum – starting from zero rpm up to maximum. Even though a moving foil would probably deliver slightly higher performance, the construction complexity would run contrary to our low cost goals. Concerning your idea for a stop-action study of airflow using Plexiglas, it sounds like a great study – I have never heard of anyone approaching the subject in that manner. You have some really good ideas here – I hope you will follow through and experiment with them. Since development of boundary layer turbines will be ongoing for years to come, your experiments will be an important contribution to this engine’s progress. -- Ken |
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01/24/03 Pedro J. Rivera email: ce_pjrivera@yahoo.com location: Sabana Grande, Puerto Rico I want to know facts from the tesla engine, for example charts that specifies volumetric flow, pressure, dimensions and number of disks vs. horsepower, torque and rpm. Also limitations on dimensions, materials and temperature. For example if I want to build one how much is the power per dollar. |
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A: To give you a rough idea of where to start, Tesla built a turbine with 25
disks, 10 inches in diameter with a 0.0325 inch spacing that delivered 110
horsepower from a steam flow of 38 pounds per horsepower per hour at 150 psi,
spinning at 18,000 rpm. He did not mention the torque ratings.
Generally speaking, the horsepower rating is directly proportional to the total disk surface area. If you cut the disk count by 50 percent, horsepower will decrease 50% – all other factors remaining unchanged. As far as materials are concerned, stick with 316 stainless steel for safe tensile strength and resistance to heat destruction. You shouldn’t have any trouble if you limit the nozzle heat to about 1800 degrees F. Also, using steam injection at the nozzle helps by lowering the flame temperature and increasing fluid mass. As far as charts are concerned, look in our Useful Charts & Data section for information. Finally, we cannot speculate on dollar per horsepower factors – there are too many variables. -- Ken |
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01/22/03 James Farley Subject: Heat Thanks for posting your information on the internet. I personally have a lot of vision for using disk turbine technology. One problem I have with your site, however, is that you call heat useless. On page ptbc18.htm, you state: The results, compared to continuous burn, are: more of the potential energy of the combustible mixture is transformed into kinetic gas energy, less into useless heat -- which transforms into higher overall engine efficiencies and lower NOx production. But as far as I have heard, heat makes all gases expand, and greater expansion=greater pressure (within the same volume)=greater kinetic energy in the gas leaving the inlet nozzle of your turbine. If you have a surge tank where pressure can be stored (maybe not feasible with the pulse combustion model), then you would indeed see the benefit of adding heat to the gas. I guess that's basically how a steam boiler works... Anyways, I find the reading fascinating, and am glad that people are actually resurrecting this "older", superior technology. Keep up the good work! |
| A: Thanks for your response. The principle of kinetic energy involves elements such as rate of expansion, direction of resultant energy, momentum, etc. The analogy is similar to the guy who pushed down on a nail head with his bare hand for four hours vs. the guy who whacks it two or three times with a hammer. The expended energy is the same, the results are not. |
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01/22/03 Fred I. White Subject: Help? I wonder if any of your members might consider assisting me with a pet project. I need a small Hero engine that runs on compressed air, i.e. a motor. To my knowledge there is no commercial product anything like the unit I have in mind. Those available, such as die grinders, run too fast, have too much power, and make terrible noises as they gobble up prodigious amounts of air. What I need could run no faster than about 3,600 rpm, and would have torque comparable to a small DC motor that pulls 300 milliamps at 6 VDC. But one of the virtues of this type of turbine is that the torque can be increased by simply making the arms longer, within the space available. The shaft I need to turn will carry an unbalanced weight of an ounce or so and be oriented vertically. It will not be coupled in torsion in any way; its job is to produce an orbital motion of the whole assembly. In short, it's a "shaker." I hope to keep air consumption very low. To that end, it may be necessary to do some bench tests to see what shape and dimensions of nozzle give the best force per unit of air. I expect to pay the usual rates for this kind of work. If you could refer me to one of your members or providers I would be very grateful. Thanks, Fred I. White PO Box 1307 Bandon, OR 97411 |
| A: Anyone able to help Fred? |
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Scott Beach Subject: TO: Richard Gideon (Angled Outer Teeth) Richard: You reported that, "After that I then cut a saw tooth edge on the center discs, this produced an additional 500 Plus RPM." I suggest that you also cut angled teeth on the outer discs. The angles should be perhaps 15 degrees, which would deflect gas toward the center of the disc pack. This might reduce the amount of gas that blows past the outer surfaces of the two outer discs. |
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01/22/03
Scott: Thank you for the suggestion. While angled teeth would probably reduce the air loss it would not eliminate it. Also the addition of teeth to the two outer discs of a large stack, even if it did not leak, percentage wise they would not be able to produce an appreciable increase in performance. While the work needed to cut the angled teeth would increase exponentially. But by all means keep on researching Tesla's turbine, if you think you have an improvement build a simple model and try it out. It can be an exciting quest. Just because Tesla was an extraordinary smart man does not mean you cannot improve on his work. -- Richard Gideon spotteddogs@iwic.net |
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01/17/03 Gordon Henry email: gordonh@lakedalelink.net Subject: Disk edges I am fascinated by your web sites! I have read them thoroughly, but am wondering how the edges of the center disks are shaped??? Are they square, rounded, or pointed? It seems to me that a modified point or taper would provide a better transition of the working fluid from the divergent area to the disk spacing. Thus creating less turbulence in the disk spaces, or would this create too much of a gap between the disks and shroud? By the way how much of a gap have you been using between the disks and shroud in your experiments? I have started converting my snowmobile engine but as you said I don't want to waste time reinventing the wheel if you or somebody else has already done it and found it not to work! |
| A: The disk edges are simply cut square, but as you pointed out, may prove to be more efficient with rounded edges. We are using a 0.125-inch gap between the disk edges and the case ring, but this could be reduced to 0.0625-inch if you are careful to exactly center the ring around the disks. At high speeds the disks grow by as much as 0.03125-inch and could contact the case if the gap is too small. -- Ken |
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01/17/03 name: Drew MacMichael email: cascodrew@yahoo.com subject: micro gas turbines I am interested if any of you know of someone working on a super small turbine engine. I know of some RC manufacturers of units as small as 6lbs., but I am looking into something smaller. Maybe 1-2 lbs without fuel, or oil. |
| We'll post your question on our forum for member response. |
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01/15/03 name: Frank Sander email: fsander@midwest.net subject: TO: Maxsmoke (answer to 11/22/02 comments) You were talking about electrostatic and electromagnetism for lift. You might try using Tesla's ideas on frequencies, I believe he stated that at the right frequencies you could nullify gravity, my thinking may be way off on what I read, but an idea. |
| A: Tesla also mentioned that he had solidified either material between parallel plates charged with high frequency, high voltage electricity. -- Ken |
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01/14/03 Trent Mohn tmohn1@neo.rr.com Subject: Waste heat turbine Thanks for the reply. I think you may be correct about the power assist driving an alternator or even an air compressor for air conditioning. I don't know how much torque I could get out of a turbine though. I haven't heard anyone talk about torque from one. All I have read about is rpm. I would think output from a turbine in horsepower or torque would be important. Has anyone had any information about this? |
| A: Turbines have been used since WWII as auxiliary power units (APUs) to drive everything from generators to compressors. Gearing will take care of any torque problems you run into. -- Ken |
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01/14/03 Trent Mohn tmohn1@neo.rr.com Subject: (continued from 12/26/02) Amen to that. I'm on your side on this one. Why hasn't the automotive research accomplished what the electronics industry has in the past 20 years??? |
| A: It’s relatively simple – money. The auto industry does not invest in R&D unless pressured into it by government or customers. The electronics industry must push the bar higher continuously to maintain its customer interest. Autos are geared more towards lower-level self-serving types with a need to zoom. -- Ken |
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01/14/03 name: Adam email: drag0n75@hotmail.com subject: Disc blower comments: I want to make a tesla style blower. want to know if you could tell me the best setup? And how much cfm and psi it could produce. I want to try and keep it to around 5 pounds and under and a disc size of 5 inches or less. Also the best drive for the blower, electric or mechanical? Thanks. |
| A: We aren’t working with Tesla blowers yet. We may get into blowers and compressors in 2004. -- Ken |
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01/12/03 Trent Mohn tmohn1@neo.rr.com Subject: Waste heat turbine Hello all, Love this site. My question is why can't we use the waste heat from the exhaust of an internal combustion engine to turn a turbine and attach this to the harmonic balancer end of an engine to increase its horsepower output? |
| A: You could recuperate latent or waste heat from a piston engine and use it to drive accessories or power assist hydraulics – similar to what Ford is doing. Rather than adding efficiency directly to a piston engine, it may work better to eliminate the parasitic elements such as the alternator from the main engine and use an auxiliary turbine to power them. -- Ken |
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01/10/03 name: Steve Redmond email: skiprock@earthlink.net Subject: Books, turbines, compressor wheels I've enjoyed reading your site over the last year and have been working toward doing some experimenting of my own. In order to do this I cast and built a Dave Gingery lathe by hand from scrap aluminum pistons, and have just added a milling attachment of my own design with a rotary table. I'm looking forward to making some disk rotors soon. I'm writing to draw your attention to the following books, all available from Traplet books (http://www.traplet.com) a British modeling publications house -- in the U.S. you can call 1-800-695-0208 and order them from their affiliate here in the States. I ordered mine and received them within a week. Each has detailed construction plans and instructions, calculations and general theory for construction for small gas turbine engines (up to 190 Newtons thrust). The most recent is the Kamps book (second edition). But the Schreckling books are equally interesting. Model Jet Engines (second edition) by Thomas Kamps This one is encyclopedic and up to date. Plans and instructions for turbojet with a commercial compressor wheel. Gas Turbine Engines for Model Aircraft by Kurt Schreckling (the radial compressor is actually built of plywood and turns at 75,000 rpm.) This is a real hands-on book for building an engine. The Model Turbo-Prop engine by Kurt Schreckling This one addresses the mechanical power-output side of things which is what what we will need for non-aviation applications like power generation. He shows a number of different driven shaft options in small working engines, as well as providing plans and instructions for building a concentric shaft turboprop engine using a commercially available compressor wheel. Ken -- So far we seem to be conceptualizing on the power rotor in our experiments, that is to say extracting power. But generally there are three rotors in small shaft turbine engines. Compressor, compressor driving turbine and output turbine. Clearly one of the most important parts of a turbine engine is the compressor wheel. Schreckling uses a home built reverse curve bladed radial flow wheel. Since the Tesla turbine is also a radial flow wheel, I wonder how it measures up as a compressor in terms of efficiency and pressure vs. kinetic flow at turbine RPMs? And what the rotor weight difference is for equivalent mass flow? By comparison, a conventional small axial flow power turbine wheel is relatively simple to build out of sheet metal -- I believe simpler and lighter than the Tesla disk set. And I wonder if the Tesla disks advantages are more suited to another section of the engine. It's the compressor wheel that's hard to build in these model engines, and most builders purchase off-the-shelf turbocharger wheels. I'm very interested in hearing from anyone who has experimented with driven rotors in Tesla's compressor mode. Driven rotors are what I'd like to focus on in my own initial trials. |
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A: At this point it's anyone's guess -- which design is better. The only
reason bladed compressors are more widespread is due to the ignorance on the
part of engineers toward Tesla's designs, and the amount of R&D resource put
into conventional design. We spoke with a group of engineers who claimed higher
efficiencies on water pumps using disks with blades between them.
This is a fascinating area of study and experimentation, and we really need your work and results for direct combustion systems. Thanks for the reference material; we'll post it for all to use. -- Ken |
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01/10/03 Oystein Lande Subject: Tesla turbine research link Thanks for an interesting website! Below is a very interesting link containing some scientific analysis of the Tesla turbine. Also a thesis on the turbine done in Queensland University of Technology. http://tesla.stemwinder.org |
| A: Thanks for your information and continuing interest. -- Ken |
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01/08/03 Tom Sperry Subject: Source of disks for Tesla turbine Has anyone experimented with using 'junk mail' CD disks for low-temperature Tesla rotors? Finally we have a use for AOL! |
| A: We have designed and built a small educational unit using two CD's and low pressure (10 psi) compressed air. Works great for initial tests. -- Ken |
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01/07/03 name: Greg Faulkner email: greg_faulkner@hotmail.com location: Quebec, Canada Subject: Electropolishing Using 12 volts DC, a lead anode and the SS316 turbine plate as cathode in a 1/3 99% sulphuric acid 2/3 70% phosphoric acid one can produce a very high lustre finish by a process called "Electropolish". It sure works great and will give you the smoothest finish that cannot be achieved by mechanical polishing alone. web: www.atomex.com |
| A: Thanks for your valuable information. It's going to be lots of these small detail solutions that will work together to produce a perfect design. -- Ken |
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01/04/03 Tony Hudson t305100@lycos.co.uk Subject: Efficiency Ok, I'm confused! Why, well it's a straight forward enough question; "As a prime mover, what is the efficiency of the TT, assuming a 'state of the art' TT treated & installed in the same way as say a car engine for instance?" I am not interested in the fuel used or the working fluid, or, for that matter an ironic critique on my question. Just how much energy flowing through the TT can be turned to work via the output shaft? I have gathered so much conflicting information, ranging from obvious BS/myth to more reasonable sounding, but non-qualified 'research', that I find myself going round in circles! So to state the question somewhat differently: How does a TT compare, in terms of efficiency as an energy transducer with either a 'state of the art' IC engine (probably diesel then) or a modern bladed turbine? |
