Carnot Revised & Disproved

To commence, the working fluid to be steam, to be compared are two standard Rankine cycles. I.e, comparing like with like based upon a well-known and well-understood cycle. For a diagram assume a square/rectangle, where vertical = pressure and horizontal = entropy, a Ps diagram, as usual. The cycles commence with position (h1) in the lower left of this Ps diagram. Both cycles shall be analysed with Carnot's own formula and the result to be referenced against the real world formula of (W/Qin) or (Work done / Heat supplied). And, as Carnot and EVERY textbook states, the real world efficiency CANNOT EVER surpass Carnot. We'll see if that's true, NB: Two cycles will be compared that are identical, except for the parameters, and the comparison will be done with identical, well known formulae.

Dat source: NBS/NRC Steam Tables by Lester Haar, John S. Gallagher & George S. Kell; pub: Hemisphere Publishing Corp.; part of NSRDS (National Standard Reference Data System, USA). The tables are the result of research work by IAPS.

The first cycle: Standard Carnot/Rankine, wide temperature range, that is between 873K & 348K, and a pressure range from150 bars to 0.4 bars, please refer to pages 28 and 151 in the steam tables if you wish to check the parameters given below:

h1 = 313.96 kJ/kg, T1 = 348 K, P1 = 0.4 bar, s1 = 1.0 h2 = 326.03 kJ/kg, T2 = 348 K, P2 = 150 bar, s2 = 1.0 h3 = 3,583.2 kJ/kg, 3 = 873 K, P3 = 150 bar, s3 = 6.68 h4 = 2,295 kJ/kg, T4 = 348 K, P4 = 0.4 bar, s4 = 6.68

eta as per Carnot: (1-(Tl/Th)) = ((Th-Tl)/Th) = eta of 60.1%, whilst: eta real world: (W/Qin) = ((h3-h4)/(h3-h1)) = eta of 39.4%

So far so good. But, didn't Watt and Brunell say something about pressure? Namely that pressure should be included in an efficiency calculation or estimate since pressure is more important than mere temperature. Wouldn't that make sense? After all, PA = Force, and without a difference in force, no work. There can be a ratio of zillions of Ks or Rs, but without a difference in force, nothing's going to happen!

Now the second cycle: again standard Carnot/Rankine, but a narrow temperature ratio of 393K & 308K and an EXTREMELY large pressure ratio of 11,000 bars & 0.4 bars. Please refer to pages 28 and 215 in the steam tables. That's right, 11 kilo bars to 0.4 bars! So, here are the parameters for the second Rankine cycle:

h1 = 146.62 kJ/kg, T1 = 308 K, P1 = 0.4 bar, s1 = 0.5 h2 = 1,115 kJ/kg (approx), T2 = 348 K, P2 = 11,000 bar (NB), s2 = 0.5 h3 = 1,312 kJ/kg, T3 = 393 K, P3 = 11,000 bar (NB), s3 = 1.0 h4 = 313.96 kJ/kg, T4 = 348 K, P4 = 0.4 bar, s4 = 1.0

Note about the 2nd cycle: The process of Qout is a constant pressure process as is the case for the 1st cycle. However, it is not a constant temperature process as is usually the case for Rankine cycles, that is to say the nature of the Qout process is the same as for Qin. But note please that the ideal case requirement for Qin and Qout is constant pressure for the working fluid and constant temperatures for the heat source and the heat sink. Besides, I wanted to stay within the published steam data. Moreover, the cycle is still a Rankine cycle ? just in case somebody is bothered about this.

eta as per Carnot: (1-(Tl/Th)) = ((Th-Tl)/Th) = eta of 21.6%, whilst: eta real world: (W/Qin) = ((h3-h4)/(h3-h1)) = eta of 85.6%. Note that well!

Where does that leave Carnot and his universal formula? Nowhere, it's simply wrong. As I have mathematically proved above, Carnot has been surpassed on his own cycle, with the REAL WORLD formula of (W/Qin), a formula that's in use everywhere and all the time.

Carnot's famous (from an environmental point of view ?infamous') formula was or is supposed to be universally true and impossible to surpass even in theory, certainly not in practise. Every engine design had and has to submit to it, any engine promising a higher efficiency than Carnot is neither welcomed nor to be investigated, but simply to be shelved, never mind tried and tested. We mustn't try anything new, mustn't we? Everybody doubting Carnot was and is to be rubbished, usually with personal innuendo ? no doubt as an expression of the professional competence and open mindedness by those who do so. As a result we currently have engines that are mostly filthy, giving us ever-increasing levels of asthma, greenhouse effect, etc. etc. est. Apart from these we also suffer from a fuel crisis on account that heat engines have to have as wide a temperature range as possible. Of course, we are designing engines that are excellent performers when measured with a thermometer? But now, after I proved Carnot to be wrong, where does that leave us? If one wants to, FREE to THINK! Free to design engines that are efficient and environmentally clean, free to access low temperature heat sources of which we have many. Free to use SAFE nuclear energy, that is to say low temperature fuel rods with the correspondingly low level of radiation and a high rate or reusability ? and of no interest for terrorists; apart from that, they are also cheap to decommission.

That leads to the question: But what about Carnot's work? What work!? A supposedly ideal engine and its formula, but that engine NEVER worked and cannot work! Everybody repeats the Carnot formula as gospel truth; it is even used to ?prove' the first law, and therewith on occasion it is used as prove that God does not exist, I've actually seen or rather read that! How much more scientific can one get? But when I asked, I found nobody, but absolutely nobody who has ever read Sidi's book, HIS WORK, on ?The Motive Power of Fire'! I urge everybody interested in science and particularly in thermodynamics to read that book, know this: If a man would nowadays write such a book, the police would keep track of the author as a potential pyromaniac. Carnot was taken by canons and canon fire, which is visually and acoustically impressive. However, he should have made an experiment, he should have placed a canon ball onto an open surface and placed next to it a large amount of gunpowder. Had he ignited the powder he would have found that the canon ball might have vibrated, become very hot, but it would not have moved a millimetre! Never mind the high temperatures of the combusting powder. Well, that's the bad news about Sidi, now the good news, his thoughts on the constancy of heat source and heat sink temperatures and on entropy in particular have indeed been of great use and inspiration to us.

But, his universal formula is of no use, so, can we simply replace it with the real world formula of (W/Qin) that is used anyway when things come to the final analysis? Yes and no. First let us look at the good news, work and Qin contain heat energy as opposed to mere temperature, thus they contain pressure and, as has already been indicated by J. Watt and Brunell, pressure is very important. Also I have proved above that Watt's and Brunell's thoughts on the matter are or were indeed correct. However, there is a bid of bad news when we use (W/Qin) only, and that is the risk that somebody will now proclaim that perpetual engines are possible, and there would be quite a lot of these claims. However, this can be avoided by detailing the formula in the following manner: eta = (W/W+Qout). Note that the result of the modified or extended formula that I am proposing is still identical to (W/Qin), obviously since (W+Qout) = Qin. But, replacing ?Qin' with ?W+Qout' means that the 2nd law is included AND the 1st law since (W+Qout) will always be greater than work on its own. Thus the formula that I propose, namely (W/W+Qout) will not only prevent the proposal of perpetual motion machines of the first kind, it will also prevent proposals of perpetual motion machines of the second kind ? unless the proposer doesn't know anything about thermodynamics. Having said that, the formula that I propose will have difficulties coping with reheat engines, but the cycles of such devices are special cases anyway, warranting a more detailed analysis from the outset. So, the formula that I propose is not perfect, but it allows for modification when in the future our knowledge increases. In case somebody doubts the wisdom of this, please do look again at Carnot above and his absolute, perfect formula ? and what I have done to it.

Miscellaneous

A bit about myself, my primary engineering activities are in the field of thermodynamics. I have been involved in work on supersonic compressors, and on projects that attempted to recover as much of the constituents of combusted fuel as possible with the aim to add these constituents to fuel that is to be combusted, that project was a success. Unfortunately we ended up with gases that were explosive, toxic or both? Apart from that I worked on many other projects, either my own or as a consultant. I have been falsely accused in this group of wanting to build a perpetual motion machine, I do not know why, but I am sure the accusers feel smug about it. As far as engines are concerned there was and is a project that I have began and that has led to a patent application, a poster by name of Smith has pointed to this project. He has done so in a rather malicious fashion, I do not know Mr. Smith or his motivation for doing so. This project has attracted both, appraisal as well as severe criticism; consequently I redesigned the proposed engine. This proposal is now at stage where one European country wants to build a pilot plant in the 5MW to 20MW region, depending upon predictable scaling losses. Also, a large European power generation company is interested and has also investigated the proposed engine with positive results. Obviously I cannot and will not give details. All I can say is this: The cycle is not a Rankine cycle and the working fluid is not steam, but it led me to the investigation of the Carnot/Rankine cycle because it exhibits the same phenomena that I have shown above. The operating temperature range is between (approximately) 120C and about 50C, and the pressure range between 300 and 200 bars approx., much more modest than in the example above. Carnot efficiency is low but Work-to-Heat (W/Qin) conversion is high at about 50%. How it makes me a bad person when I am willing to modify my proposals upon criticism and how that implies that I am fishing for partners (I have several of these, all of them engineers) is beyond my comprehension. Perhaps those who made such hateful comments are able to explain that.

Some of you have asked why I choose to publish here. Well, there is simply no hope that this will ever be accepted under normal circumstances. Consider that the Carnot formula is held and PRINTED as gospel truth. From A-Level physics textbooks (or whatever you non-Brits consider to be worth reading =)) up to 2nd and 3rd semester textbooks, whatever field of engineering. Also, may I just point to Marks' Standard Handbook for Mechanical Engineers (McGraw Hill) or to Kempe's Engineers Year-Book (Morgan-Grampian), and these are tombstone classics! Does anyone really believe that they will? will what? Change? That those lecturers will tell their students that what they told them is, dare I say, wrong. And the students paid a lot of money for their textbooks ? do you think any of this will happen? Or do you believe that the journalists of the scientific journals will rock the boat in which they and their colleagues are sitting? Fat chance! Just read the replies of foam_on_the_lips hatred that has been slung at me by non-lecturers. However, it will be printed and published (apart from this publication on the net), for that engine is going to run.

Finally, kind thanks to those who showed willingness to give a hearing.

Regards Dietmar

Reply to
DFD
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To the Group:

He had posted his "warning" in another cluster posting that included sci.physics.relativity. Someone predicted that he would play in the nonlinear area of high pressure for his "miracle". All he is proving is that the steam tables were fudged at high pressures. He has no cycle, nothing worth purchase.

What a waste of time...

David A. Smith

Reply to
N:dlzc D:aol T:com (dlzc)

ok, so we are now going to see a working demonstration of this principle?

By the way, your steam table values are a tad off from what I found in other tables. A lot depends on exactly how they are calculated. Generally, a few points are tested and the data are used to fit an equation of state. This equation is then used to calculate the values in the tables. You have to be careful in dealing with such wide variations in pressure and temperature. I would wonder if it is likely that one would need 11000 bar in any application. That gets a bit difficult to contain.

Michael

Reply to
Herman Family

Dear Herman Family:

Its not steam, but... Guacamole is sterilized by pressurizing to 100,000 psi... Orange juice to 80.000 psi.

And you detect leaks in the delivery piping just as you do with steam delivery in naval vessels... with a broom. Where the bristles fall off when sweeping the space in front of you...

David A. Smith

Reply to
N:dlzc D:aol T:com (dlzc)

Hmmm...if in the real world, you could use all, even most of the heat energy input to a heat engine for useful work you would be doing better or much better than the ideal cycle postulated by Sadi Carnot.

What a pity you can't, not in the real world, anyway.....

So how was Dietmar convinced otherwise? His use of the steam tables, for the parameters he chose tripped him

Brian W

Reply to
Brian Whatcott

That's amazing. I didn't think there were many processes which required anything like that pressure. How popular is this particular method?

Michael

Reply to
Herman Family

snipped-for-privacy@aol.com (DFD) writes a load of garbage starting with

For starters, the preceding drivel scores highly on the crackpot index:

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A simple method for rating potentially revolutionary contributions to physics: A -5 point starting credit.

1 point for every statement that is widely agreed on to be false. 2 points for every statement that is clearly vacuous. 3 points for every statement that is logically inconsistent. 5 points for each such statement that is adhered to despite careful correction. 5 points for using a thought experiment that contradicts the results of a widely accepted real experiment. 5 points for each word in all capital letters (except for those with defective keyboards).

and a lot more...

The actual engineering content is nonsense: you can certainly get a W/Q ratio as claimed if you have working fluid at a pressure of 11000 bar, but just how he plans to get that from a thermal reservoir at

348K isnt actually explained. He clearly has no clues about thermodynamics.

Move on people, nothing to see here.

Reply to
Coriander Lexus

Dear Herman Family:

message

Generally,

It is the current rage. I was attempting to install some water+ozone as a surface disinfectant at a plant in Mexico, when I was introduced to it.

The interesting thing is, cell walls are completely transparent to diffusion at these pressures. And the quality of the foodstuff is as if you had just fresh squeezed it, or just carved up the avocados yourself.

You do have to make sure the pressurization chamber is completely full of water, with no air though. I've heard about replacement of expensive vessels due to damage that was caused either on pressurization or depressurization (I don't recall what caused it).

Altavista Advanced search with the boolean term: sterilization and (high near pressure) about 9000 hits, and the first one looks right... URL:

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David A. Smith

Reply to
N:dlzc D:aol T:com (dlzc)

I would imagine a lot of this has to deal with processes using supercritical fluids.

Reply to
Ed Ruf

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