Is Carnot efficiency valid?

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1 hour ago, Tom Booth said:

Maybe someone can explain to me how and/or why if I SUPPLY by heating, with some actual fuel or other ACTUAL, REAL, FACTUAL heat source, such as an electrical heating element 500,000 Joules of very palpable heat 400,000 joules of heat must GO MISSING or we are threatened with the dread "OVER unity" ???????

Now that you are talking to me again, please remind me how you arrive at this figure of 500kJ supplied and what is it supplied to ?

You do realise that the figure should only include energy added to the working fluid, nothing else ?

Is this 500kJ over one cycle or what ?

Edited by studiot

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33 minutes ago, sethoflagos said:

Because it didn't "GO MISSING"!

500 kJ of heat @ 500 K has been transformed to 100 kJ of Shaftwork plus 400 kJ of heat @ 400 K

It's still there but at a lower temperature. (...)

(...) Just recognise that extracting the kinetic energy from slow moving particles requires contact with particles that are almost stationary.

Sorry but that explanation goes nowhere.

Newtons laws of motion again.

If a billiard ball, slow moving or otherwise strikes a stationary billiard ball, 100% of the force is transmitted to the second ball, subtract a bit for the sound vibrations emitted, friction on the felt table top, etc. but the second ball basically takes off at the same speed as the ball that struck it and the first ball comes to a stop.

Rationalizations aside, where is the empirical data? Who did experiments that conclusively established this exact supposed limit?

Not Carnot. He had no absolute temperature scale at that time. He only made assertions about "the fall of Caloric"

14 minutes ago, studiot said:

Now that you are talking to me again, please remind me how you arrive at this figure of 500kJ supplied and what is it supplied to ?

You do realise that the figure should only include energy added to the working fluid, nothing else ?

Is this 500kJ over one cycle or what ?

The 500kJ figure is an arbitrary number.

It could be added in whatever manner. One cycle or over however many.

And I have no idea what you mean by "Now that you are talking to me again".

Who said I stopped talking to you?

My time is limited and I may not have gotten to every comment. I'm just one person.

There are probably a dozen comments I haven't had time to go back and re-read and respond to. Sorry if yours was among them. I'm trying to keep up but as I say, my time is limited.

What is it supplied to?

The working fluid within the heat engine.

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19 minutes ago, Tom Booth said:

What is it supplied to?

The working fluid within the heat engine.

Thank you, but how do you know ?

You can't just pick an arbitrary figure out of the air and say I will put in 500kJ of energy.

You are constrained by the characteristics of the system.

You can measure and adjust temperature, pressure, and perhaps volume.

You then need to calculate the energy (and entropy) interchanges from the 'observerables'.

Talking of energy you said I posted the PV diagrams.

Yes

But I also posted the TS diagrams which are of great use to engineers and I use to answer the question "What is Entropy ?"

The area of a PV diagram gives you energy and entropy was introduced originally to answer the question "We need a variable to go with temperature (an observable) in the same manner to also help us calculate energy.

Plots of such varaible pairs are called 'indicator diagrams'.

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22 minutes ago, Tom Booth said:

Sorry but that explanation goes nowhere.

A deliberate refusal to acknowledge the points of view of others when they challenge with your own 'faith'.

26 minutes ago, Tom Booth said:

Newtons laws of motion again.

If a billiard ball, slow moving or otherwise strikes a stationary billiard ball, 100% of the force is transmitted to the second ball, subtract a bit for the sound vibrations emitted, friction on the felt table top, etc. but the second ball basically takes off at the same speed as the ball that struck it and the first ball comes to a stop.

Deliberate misdirection of the discussion and wrong. The vast majority of collisions are not head on. Kinetic energy gets shared out. There is a nett flow of heat to the cold sink.

28 minutes ago, Tom Booth said:

Rationalizations aside, where is the empirical data? Who did experiments that conclusively established this exact supposed limit?

Conspiracy theory.

34 minutes ago, Tom Booth said:

Not Carnot. He had no absolute temperature scale at that time. He only made assertions about "the fall of Caloric"

Irrelevant historical detail.

You really don't have the slightest interest in being enlightened do you? Why exactly are you here?

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How do I know?

Suppose for example there is an engine similar to the one in my experiment.

There is a plate on the bottom (heat exchanger) for heat input.

Suppose instead of a metal plate there is a small container of water, perfectly insulated on all sides except where in contact with the working fluid inside the engine.

The water in the container is heated up by an electrical heating element to 100°C

Ambient is 75°F

That works out, using the Carnot efficiency limit formula to 20%

So for every 100 Joules added to heat up the water, (to maintain it at 100°C while the engine is running) which heat has nowhere to go but into the engine and into the working fluid (ideally, discounting losses due to conduction of heat through the engine body) only 20% of the heat being added to maintain the water at 100°C can be utilized by the engine to convert into work output. The other 80% passes through to the sink or "cold reservoir". (According to the current interpretation of the formula being universally taught by academia today afaik.)

So, choosing an arbitrary number of 500,000 joules of heat added to the water to maintain the 100°C temperature, for every 500kJ added to the water 400kJ should appear at the sink while the engine is operating, converting the other 100kJ to work output

Edited by Tom Booth
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Thank you, but that wasn't what I asked you.

I asked you how you measure this supposed energy input to the working fluid.

Not guesswork thank you.

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24 minutes ago, studiot said:

Thank you, but that wasn't what I asked you.

I asked you how you measure this supposed energy input to the working fluid.

Not guesswork thank you.

If using an electric heating element to maintain the temperature of the water?

Something like 500 watts for about 15 minutes would be equivalent to 500kJ if I'm not mistaken.

As I said, it's an arbitrary figure taken as an example, that's all.

Edit: Getting out a calculator:

About a minute and a half more

16.66666..... minutes

Edited by Tom Booth
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1 hour ago, Tom Booth said:

Sorry but that explanation goes nowhere.

Newtons laws of motion again.

If a billiard ball, slow moving or otherwise strikes a stationary billiard ball, 100% of the force is transmitted to the second ball, subtract a bit for the sound vibrations emitted, friction on the felt table top, etc. but the second ball basically takes off at the same speed as the ball that struck it and the first ball comes to a stop.

Rationalizations aside, where is the empirical data? Who did experiments that conclusively established this exact supposed limit?

Not Carnot. He had no absolute temperature scale at that time. He only made assertions about "the fall of Caloric"

The 500kJ figure is an arbitrary number.

It could be added in whatever manner. One cycle or over however many.

And I have no idea what you mean by "Now that you are talking to me again".

Who said I stopped talking to you?

My time is limited and I may not have gotten to every comment. I'm just one person.

There are probably a dozen comments I haven't had time to go back and re-read and respond to. Sorry if yours was among them. I'm trying to keep up but as I say, my time is limited.

What is it supplied to?

The working fluid within the heat engine.

Nobody has ever made a Carnot cycle engine, for one very obvious reason -  which you would have realised if you had learnt the necessary thermodynamics. Because the essence of a Carnot cycle is that it is 100% reversible, with no losses, all its processes have to take place infinitely slowly. It also has to be perfectly insulated, so that the adiabatic stages can be exactly adiabatic. So such a machine can't be made. Its cycle can only be calculated on paper.

The best we can do is assess the efficiency of real machines compared to the idealised Carnot efficiency. 150 years of engineering experience confirms that no heat engine has ever equalled or exceeded the Carnot efficiency. So, not only does it appear to be correct  on theoretical grounds but practical experience also indicates it seems to be right.

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Of course, if we are going to get down to brass tacks and do an actual experiment, some sort of temperature regulator, electrical meter and so forth would be needed.

42 minutes ago, sethoflagos said:

A deliberate refusal to acknowledge the points of view of others when they challenge with your own 'faith'.

Deliberate misdirection of the discussion and wrong. The vast majority of collisions are not head on. Kinetic energy gets shared out. There is a nett flow of heat to the cold sink.

Conspiracy theory.

Irrelevant historical detail.

You really don't have the slightest interest in being enlightened do you? Why exactly are you here?

You are resorting to a decent into character assassination. An ad hominem.

I'm considering your opinions or point of view. I simply do not find your argument convincing. It has nothing to do with "belief".

You made an assertion which IMO is not supported. You are at liberty to try and convince me of the correctness of your assertions. I'm listening.

I think how and when and by whom a science was first established is a perfectly legitimate question not a "conspiracy theory".

As far as dispersal or distribution of the heat energy. Sure. So what?

That is what results in the expansion of the gas. The expansion work pushes the piston.

Either the heat is used up doing work or it gets "rejected" to the sink. No mystery. Everything can be accounted for.

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33 minutes ago, Tom Booth said:

If using an electric heating element to maintain the temperature of the water?

Something like 500 watts for about 15 minutes would be equivalent to 500kJ if I'm not mistaken.

As I said, it's an arbitrary figure taken as an example, that's all.

Edit: Getting out a calculator:

About a minute and a half more

16.66666..... minutes

I thought so.

You said you are an engine mechanic - a very respectable trade I know such people who have many innate skils I don't possess. They find it easy to for instance dissemble, fix and reassemble aBorg-Warner auto box whilst I know from personal experience of much simpler mechanics that I would struggle for days and probably not succeed with a B-W.

However you anser brings us to appreciating the difference between power and energy.

I have assumed you know this.

Total energy (you have a total energy meter ?) used to keep the waterbath temperature constant for 15 minutes.

Do you think 15 minutes is enough ?

I don't.

So over a longer period you can measure the energy to maintain that waterbath temperature.

So what ?

How do you know what proportion of that input actually goes into the working fluid ?

And over that time how many cycles has you engine completed ?

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3 hours ago, Tom Booth said:

As I vaguely understand the so-called "Over Unity" concept, which I by the way DO NOT espouse in any way personally that would constitute a ratio of 500,000 Joules in and > 500,000 Joules out. 500,000 joules SUPPLIED by ME or my heating element or whatever and some additional amount supplied by the "Orgone energy" or some such preposterous nonsense.

The proposed ideas and the links provided speaks in favour of physically impossible devices usually labelled "over-unity".

A possible cause, (good point @sethoflagos) :

2 hours ago, sethoflagos said:

I think one of the main issues is a very confusing terminology.

When over unity support creeps into a discussion it is interesting to know if it is due to bad faith argumentation or ignorance regarding physics.

I'll postpone my pictures and attempts at a discussion about a simplified system until we know what the agenda is.

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3 minutes ago, Ghideon said:

The proposed ideas and the links provided speaks in favour of physically impossible devices usually labelled "over-unity".

A possible cause, (good point @sethoflagos) :

When over unity support creeps into a discussion it is interesting to know if it is due to bad faith argumentation or ignorance regarding physics.

I'll postpone my pictures and attempts at a discussion about a simplified system until we know what the agenda is.

I think we can guess the agenda from Tom's previous thread on the "ice bomb engine": https://www.scienceforums.net/topic/124996-the-ice-bomb-thermal-engine/page/2/#comments

As often with the crank fraternity, Tesla is behind it. In this case though, interestingly, it is not  the usual misunderstood magnetism but another notion Tesla had, which was to create an engine that rejected no waste heat.

So it's perpetual motion of the second kind. Which is more fun than a mere violation of conservation of energy, admittedly. The ice engine was great - I enjoyed it immensely.

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10 minutes ago, exchemist said:

(...) 150 years of engineering experience confirms that no heat engine has ever equalled or exceeded the Carnot efficiency. So, not only does it appear to be correct  on theoretical grounds but practical experience also indicates it seems to be right.

'Seems to be right".

How would we know if an engine exceeded the Carnot efficiency? Ever?

Has every engine ever built been carefully tested with energy input and output measured and compared to what exactly?

How do I determine the Carnot efficiency of my toy LTD Stirling engine?

Well, factually, out of the box. I cannot.

Properly speaking, Carnot "efficiency" is a supposed property of the environment. The two "reservoirs'.

The engine itself does not enter into consideration in any way shape or form.

So I can calculate the supposed "efficiency" inherent in a supposed "reservoir" of heat elevated above a lower "reservoir". That is all.

So, how do we determine the work potential of this upper reservoir?

How much heat exactly does it contain?

Infinite? Why it will never go any lower in temperature?

Wild!

Well what volumes of heat can I get out of this "reservoir" at any one time? 100 Joules? 1,000? 1,000,000?

Doesn't matter, really? As much as I might be able to utilize?

Hmmm. Sounds too good to be true but OK, if you say so.

So what has any of this got to do with my engine? Nothing.

How could I determine the actual efficiency of my engine?

Not possible.

As Carnot so-called "efficiency" is actually nothing but the temperature difference OUTSIDE OFF my heat engine, there is nothing anyone can do to actually challenge this fantasmagorical fantasy. It's "unfalsifiable".

What is the Carnot efficiency of a cardboard box?

Exactly the same as any engine.

The same.

How about a pair of night slippers?

The same.

These "reservoirs" have no actual properties. No volume. No energy content. No quantity of heat that can actually be determined.

How much heat is available from a "reservoir" at 212°F ?

Well....

No way to know with just that information alone.

The entire proposition is fantasmagorical and meaningless.

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15 minutes ago, Tom Booth said:

You are resorting to a decent into character assassination. An ad hominem.

No it isn't. You can't play the victim card when you're the aggressor. I'm simply calling you out.

20 minutes ago, Tom Booth said:

I'm considering your opinions or point of view. I simply do not find your argument convincing.

No. You continually misdirect the discussion by ignoring central themes and cherry picking peripheral trivia to have a snipe at.

26 minutes ago, Tom Booth said:

It has nothing to do with "belief".

You're bringing absolutely nothing to the table to support your views other than blind persistence. Call it belief, faith, or just plain trolling: the one thing it isn't is science.

32 minutes ago, Tom Booth said:

You made an assertion which IMO is not supported. You are at liberty to try and convince me of the correctness of your assertions.

Your opinion carries less weight here than you imagine. I see no point in trying to share knowledge with someone who has no interest in it.

What are you doing here, Tom?

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Screenshot from the video @Tom Booth. It would be easier to quote text...

You claim the video is based on your ideas and the video promotes devices that are impossible according to established physics.

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22 minutes ago, Tom Booth said:

'Seems to be right".

How would we know if an engine exceeded the Carnot efficiency? Ever?

Has every engine ever built been carefully tested with energy input and output measured and compared to what exactly?

How do I determine the Carnot efficiency of my toy LTD Stirling engine?

Well, factually, out of the box. I cannot.

Properly speaking, Carnot "efficiency" is a supposed property of the environment. The two "reservoirs'.

The engine itself does not enter into consideration in any way shape or form.

So I can calculate the supposed "efficiency" inherent in a supposed "reservoir" of heat elevated above a lower "reservoir". That is all.

So, how do we determine the work potential of this upper reservoir?

How much heat exactly does it contain?

Infinite? Why it will never go any lower in temperature?

Wild!

Well what volumes of heat can I get out of this "reservoir" at any one time? 100 Joules? 1,000? 1,000,000?

Doesn't matter, really? As much as I might be able to utilize?

Hmmm. Sounds too good to be true but OK, if you say so.

So what has any of this got to do with my engine? Nothing.

How could I determine the actual efficiency of my engine?

Not possible.

As Carnot so-called "efficiency" is actually nothing but the temperature difference OUTSIDE OFF my heat engine, there is nothing anyone can do to actually challenge this fantasmagorical fantasy. It's "unfalsifiable".

What is the Carnot efficiency of a cardboard box?

Exactly the same as any engine.

The same.

How about a pair of night slippers?

The same.

These "reservoirs" have no actual properties. No volume. No energy content. No quantity of heat that can actually be determined.

How much heat is available from a "reservoir" at 212°F ?

Well....

No way to know with just that information alone.

The entire proposition is fantasmagorical and meaningless.

Do you really think the designers of heat engines don't measure their efficiency? I spent the last decade of my career talking to designers of engines and turbines for ships and power plants. I can assure you that the fuel efficiency of their machines was one of their top preoccupations, and that comes down to thermal efficiency, which was often quoted. Every power plant operator knows the efficiency of their generation plant. It is absolutely central to their business.

Unlike you, they were not just futzing about with hair dryers. 😁

Edited by exchemist
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2 minutes ago, sethoflagos said:

No it isn't. You can't play the victim card when you're the aggressor. I'm simply calling you out.

No. You continually misdirect the discussion by ignoring central themes and cherry picking peripheral trivia to have a snipe at.

You're bringing absolutely nothing to the table to support your views other than blind persistence. Call it belief, faith, or just plain trolling: the one thing it isn't is science.

Your opinion carries less weight here than you imagine. I see no point in trying to share knowledge with someone who has no interest in it.

What are you doing here, Tom?

What am I doing here?

I would say it is something like "peer review" if I were a scientist.

I did an experiment and thought the results were rather curious and worth sharing to see what others think about it.

It was mentioned by a moderator that I have to make all the details of the experiment known so that others can replicate it.

That would be interesting and much appreciated.

Getting others points of view on experimental procedures and ways to improve the experiment are valuable, potentially.

I would continue to share whatever progress is made and post additional experiments, if there is an interest.

I'm not trying to "prove" or "disprove" one POV or the other.

Experiments don't have, or are not supposed to have a predetermined outcome.

Academia (the various online educational resources) all use the Carnot equation as I have here.

If 500,000 Joules are provided to an engine at the given temperatures 400,000 will be "rejected" into the sink.

Can this actually be verified experimentally or is this teaching just being perpetuated generation after generation without anyone ever actually taking the measurements?

10 minutes ago, Ghideon said:

Screenshot from the video @Tom Booth. It would be easier to quote text...

You claim the video is based on your ideas and the video promotes devices that are impossible according to established physics.

You mean like the drinking bird?

That is an actual thing you know.

15 minutes ago, exchemist said:

Do you really think the designers of heat engines don't measure their efficiency? I spent the last decade of my career talking to designers of engines and turbines for ships and power plants. I can assure you that the fuel efficiency of their machines was one of their top preoccupations, and that comes down to thermal efficiency, which was often quoted. Every power plant operator knows the efficiency of their generation plant. It is absolutely central to their business.

Unlike you, they were not just futzing about with hair dryers. 😁

Calculating FUEL efficiency is pretty straightforward.

Miles per gallon.

Carnot so-called "efficiency" is something all together different.

Unfalsifiable yet inescapable.

Power plant, turbines whatever.

Carnot efficiency is calculated from a temperature difference.

Suppose a turbine puts out cold air below ambient. How would the Carnot efficiency of the turbine be determined, I'm curious to know.

Working as a mechanic I once got a job that started as a temporary position replacing an employee who had an accident.

The accident was he was using an air impact wrench and broke his finger off because it had been cryogenically frozen by the exhaust from the air tool he was using.

So, a turbine exhaust using compressed air can be well below ambient. Is this correct?

What temperatures then would be used to determine Carnot efficiency?

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1 hour ago, Tom Booth said:

You mean like the drinking bird?

That is an actual thing you know.

You believe the screenshot from the video describes how a drinking bird works? You may reduce your confusion by posting references to written material instead of videos.

Anyway, your comment highlights some of the issues; the video contains existing things mixed with non-mainstream concepts.

Edited by Ghideon
clarification
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54 minutes ago, Tom Booth said:

What am I doing here?

I would say it is something like "peer review" if I were a scientist.

I did an experiment and thought the results were rather curious and worth sharing to see what others think about it.

It was mentioned by a moderator that I have to make all the details of the experiment known so that others can replicate it.

That would be interesting and much appreciated.

Getting others points of view on experimental procedures and ways to improve the experiment are valuable, potentially.

I would continue to share whatever progress is made and post additional experiments, if there is an interest.

I'm not trying to "prove" or "disprove" one POV or the other.

Experiments don't have, or are not supposed to have a predetermined outcome.

Academia (the various online educational resources) all use the Carnot equation as I have here.

If 500,000 Joules are provided to an engine at the given temperatures 400,000 will be "rejected" into the sink.

Can this actually be verified experimentally or is this teaching just being perpetuated generation after generation without anyone ever actually taking the measurements?

You mean like the drinking bird?

That is an actual thing you know.

Calculating FUEL efficiency is pretty straightforward.

Miles per gallon.

Carnot so-called "efficiency" is something all together different.

Unfalsifiable yet inescapable.

Power plant, turbines whatever.

Carnot efficiency is calculated from a temperature difference.

Suppose a turbine puts out cold air below ambient. How would the Carnot efficiency of the turbine be determined, I'm curious to know.

Working as a mechanic I once got a job that started as a temporary position replacing an employee who had an accident.

The accident was he was using an air impact wrench and broke his finger off because it had been cryogenically frozen by the exhaust from the air tool he was using.

So, a turbine exhaust using compressed air can be well below ambient. Is this correct?

What temperatures then would be used to determine Carnot efficiency?

They know the temperature of combustion inside their machines. They have to, to choose the right alloys, calculate expansion, estimate expected NOx generation for emissions compliance, and all manner of other things. You have no conception of how much detailed work goes into the design of an industrial engine or turbine.

A power turbine does not put out exhaust below ambient, obviously. You are, as you so often do, introducing irrelevant anecdotes to muddy the discussion.

You can get obviously get Joule-Thomson cooling by expansion from the outlet of a compressed air supply. But we are not, I say again NOT going to get distracted by that latest irrelevance of yours.

What are you doing here, Tom?

Edited by exchemist
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Well well well,

I pause to have lunch and go to Tescos and you have stopped talking to me again.

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53 minutes ago, Ghideon said:

You believe the screenshot from the video describes how a drinking bird works? You may reduce your confusion by posting references to written material instead of videos.

Anyway, it highlights some of the issues; the video contains existing things mixed with non-mainstream concepts.

Sorry, I didn't realize that was a screenshot of something you considered important. I don't.

I can take a look if you want, but what's supposed to be significant about it?

Not my diagram. But at a glance, it looks like an energy flow diagram of the drinking bird.

Give it a push. User input (starter)

Environmental input: heat on the bottom end.

Irretrievable loses: friction etc.

Output: mechanical energy and cold air.

The birds cold head does cool the air some I suppose, and there is some mechanical activity going on.

Recycled heat?

Not sure about that. Why bother? The environmental heat isn't going anywhere.

Some friction results in heat which going into the environment might find its way back to the birds abdomen. Maybe performance could be improved by attaching a flexible heat pipe between the pivot bearing and the abdomen. Would that actually raise the input temperature any? Not likely IMO.

Heat locked away in the cold air/evaporating moisture?

Any way to get the water to condense and use the heat of condensation? I wonder.

Anyway the bird operates without all that additional potential heat recovery.

Don't see where such a chart should alarm anyone or be considered particularly extraordinary or controversial.

Am I missing something?

Anyway, I'll likely be busy the rest of the day. I've promised my wife I would install some additional power outlets in the kitchen. She's tired of running appliances off extension chords. Also the living room needs sheetrocking and additional outlets, not to mention the usual daily chores I've been neglecting.

Edited by Tom Booth
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1 hour ago, Tom Booth said:

What am I doing here?

I would say it is something like "peer review" if I were a scientist.

I did an experiment and thought the results were rather curious and worth sharing to see what others think about it.

On 1/25/2023 at 11:08 AM, exchemist said:

The Carnot cycle is a theoretical, ideal thermodynamic cycle, with no losses, that enables the maximum efficiency of any heat engine cycle to be determined. http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/carnot.html

All real heat engines are less efficient than this, small ones usually much less, as the incidental losses are large compared to the heat throughput.

And yet a couple of hours later you continued with:

On 1/25/2023 at 2:34 PM, Tom Booth said:

According to the Carnot formula, an engine with a sink at absolute zero would be 100% efficient.

At 100% efficiency, all the heat would be converted to work output so no heat would flow into or out from the sink.

And were again corrected:

On 1/25/2023 at 5:25 PM, sethoflagos said:

Reread my first point in this post. You're conflating the Carnot limit with actual machine isentropic efficiency. They are entirely different concepts. Confusing the two leads to absurd conclusions especially at absolute zero.

Again focus on the phrase 'maximum efficiency'. Can we agree that this is different from 'actual efficiency'?

Now you say:

1 hour ago, Tom Booth said:

How could I determine the actual efficiency of my engine?

Not possible.

As Carnot so-called "efficiency" is actually nothing but the temperature difference OUTSIDE OFF my heat engine, there is nothing anyone can do to actually challenge this fantasmagorical fantasy. It's "unfalsifiable".

What is the Carnot efficiency of a cardboard box?

We are going around and around in circles because you fail to understand the difference between an actual real world efficiency and a theoretical limit, despite having this explained to you by several parties.

What are you really doing here?

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3 minutes ago, sethoflagos said:

And yet a couple of hours later you continued with:

And were again corrected:

Now you say:

We are going around and around in circles because you fail to understand the difference between an actual real world efficiency and a theoretical limit, despite having this explained to you by several parties.

What are you really doing here?

Just as I stated previously.

You seem to just want to argue and engage in hair splitting.

My experiment was simple and straightforward.

"Carnot efficiency" predicts, according to multiple online sources, that an engine operating at the temperatures used should at best, being very very generous "reject" 80% of the heat to the cold side of the engine. Much more actually because the actual ∆T is considerably less than my estimate. calculated  based on 212°F and 75°F.

The steam reaching the engine was probably what?

So actually 90% ? 95% waste heat ?

What would you estimate we should find at the sink?

My IR camera barely read above ambient after 15 minutes at the top of the Aerogel blanket. What do you conclude from that?

Why doesn't the engine overheat in your opinion, when the sink is insulated ? I know, Aerogel is no different than air, or it conducts heat or absorbs it or something.

Fair enough. I'll drill some holes and insert temperature probes as you advised. Sounds like a great idea to me.

What is the predicted outcome?

What about something like one of these: ?

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3 minutes ago, Tom Booth said:

Just as I stated previously.

You seem to just want to argue and engage in hair splitting.

My experiment was simple and straightforward.

"Carnot efficiency" predicts, according to multiple online sources, that an engine operating at the temperatures used should at best, being very very generous "reject" 80% of the heat to the cold side of the engine. Much more actually because the actual ∆T is considerably less than my estimate. calculated  based on 212°F and 75°F.

The steam reaching the engine was probably what?

So actually 90% ? 95% waste heat ?

What would you estimate we should find at the sink?

My IR camera barely read above ambient after 15 minutes at the top of the Aerogel blanket. What do you conclude from that?

Why doesn't the engine overheat in your opinion, when the sink is insulated ? I know, Aerogel is no different than air, or it conducts heat or absorbs it or something.

Fair enough. I'll drill some holes and insert temperature probes as you advised. Sounds like a great idea to me.

What is the predicted outcome?

Wrong. Industrial diesel engines (low speed, two stroke, with an energy recovery turbine in the exhaust) can get over 50% efficiency, and combined cycle turbine installations even getting on for 60%: https://en.wikipedia.org/wiki/Combined_cycle_power_plant

The opening few paragraphs go into this a bit and even refer to how close to Carnot cycle efficiency they can get.

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Small flat ceramic heating elements.

Could slip that right inside the engine above the bottom plate to heat the working fluid directly.

Can run on a 5v USB charger or less. Maybe a few AA batteries. Possibly. Not entirely sure. I haven't had time to look over all the specs. There are all different kinds with different input voltages and outputs.

6 minutes ago, exchemist said:

Wrong. Industrial diesel engines (low speed, two stroke, with an energy recovery turbine in the exhaust) can get over 50% efficiency, and combined cycle turbine installations even getting on for 60%: https://en.wikipedia.org/wiki/Combined_cycle_power_plant

The opening few paragraphs go into this a bit and even refer to how close to Carnot cycle efficiency they can get.

"Wrong" what?