The "Ice Bomb" thermal engine

[Tom Booth]

9 hours ago, exchemist said:

Suppose the ice engine converts 5% of the heat input from the ambient surroundings into lifting the weight.

This is the confusing part, in that the ice engine does not convert ANY ambient heat into work. Does it?

Heat has to be REMOVED. As stated before, hydrogen bonding, or whatever intermolecular forces do the lifting. Molecular Internal energy, not "heat". You can't have a percentage of a negative number.

Remove x joules and convert 5% of this "heat input"?

It's not heat input, is the point. The "work" output is not a result of any  heat input. The heat REMOVAL allows an internal force to dominate, like bringing magnets a little closer together so that SNAP! A much GREATER attractive force than the tiny little nudge that brought them close enough together for the attractive force to dominate over the frictional force (in the case of magnets lying on a table) keeping them apart.

That molecular attractive force that does the actual work of lifting when the ice expands is enormous in comparison with the minute amount of heat transfer taking place.

Getting the magnets APPART again if where we, theoretically are at a disadvantage, in this analogy.

An ENORMOUS addition of heat is required to break the bond.

But we supply that heat easily, right from the surrounding atmosphere.

Now the freezer/heat pump in theory, let's say, will need to remove an amount of heat equal to that which was added outside the freezer.

But that heat is "pumped" directly to our heat engine and converted, with the result that our compressor need not work as hard as would otherwise be necessary, (completely ignoring the conversion of heat into work going on inside the freezer, this work admittedly, perhaps only slightly reducing the amount of heat that the compressor must remove.)

In theory, the mechanical output of the heat engine can serve as our compressor to run the refrigeration system. As Tesla, indeed pointed out in his 1900 article, 

Quote

"What is not converted ... can 
just be raised up" (out of the 'cold hole') "with its own energy, and what is converted is clear gain"

 Air compressors can operate at an  efficiency up to 96% when "waste heat" is utilized as advertised by the industry.

https://us.kaeser.com/products-and-solutions/rotary-screw-compressors/heat-recovery/

That is why I think the air-cycle refrigeration system is so attractive with this kind of application.

Some companies, remarkably, have boasted of air compressor energy recovery in excess of 100% under certain conditions. https://www.ien.eu/uploads/tx_etim/35724_Atlas_Copco.pdf

 

Edited May 11, 2021 by Tom Booth

[exchemist]

25 minutes ago, Tom Booth said:

This is the confusing part, in that the ice engine does not convert ANY ambient heat into work. Does it?

Heat has to be REMOVED. As stated before, hydrogen bonding, or whatever intermolecular forces do the lifting. Molecular Internal energy, not "heat". You can't have a percentage of a negative number.

Remove x joules and convert 5% of this "heat input"?

It's not heat input, is the point. The "work" output is not a result of any  heat input. 

.......[snip].........

 

Yes it does. Ambient heat supplies energy to break the hydrogen bonds in the ice crystal, increasing the chemical potential energy of the working medium. This potential energy then flows out when the temperature is reduced and the ice diverts some of that energy into work, as the ice forms and lifts the weight.  And then the cycle repeats itself.

I've deleted the rest as it just adds confusion. 

[sethoflagos]

21 minutes ago, Tom Booth said:

Some companies, remarkably, have boasted of air compressor energy recovery in excess of 100% under certain conditions.

Delete 'remarkably', replace with 'deceitfully'.

Any fool can convert work to heat with 100% efficiency.

Only a fool thinks you can do the reverse.

Until you grasp this fundamental difference between work (shaft energy, electricity, potential energy, elastic energy etc) and heat, thermodynamics will remain a complete mystery to you.

 Currently, you are treating the two concepts as equivalent in all your postings. 

[Tom Booth]

47 minutes ago, exchemist said:

Yes it does. Ambient heat supplies energy to break the hydrogen bonds in the ice crystal, increasing the chemical potential energy of the working medium. This potential energy then flows out when the temperature is reduced and the ice diverts some of that energy into work, as the ice forms and lifts the weight.  And then the cycle repeats itself.

I've deleted the rest as it just adds confusion. 

"Chemical potential energy" is not heat. The original ambient heat supplied has already been converted to something else entirely.

By lifting a weight in the freezer, the "chemical potential energy" is, at least in part, converted directly into mechanical energy, not heat. So in theory, less heat needs to be removed than what was originally supplied. It is removed to supply power to the load, the spring, or whatever our ratchet device is winding, converting the chemical potential energy into useable form and skipping heat release into the ice box altogether.

Perfect energy conversion is probably unobtainable. Some "waste heat" will likely be generated, necessitating removal, but it will be less heat, not more than what was previously added. Theoretically anyway.

Can we assume an extremely low efficiency for this ice formation?

That is, is a whole lot of heat being transfered?

Let's say the water warmed just enough for it to thaw is at approximately 32°F. To re-freez it needs to be cooled down to, approximately.... 32°F

As it crystalizes it performs work but remains at 32° F.

How much "HEAT" transfer is actually necessary to bring water from a 32°F liquid state to a 32° solid state?

There are other means and methods of transferring energy other than heat transfer, which is the whole point that Tesla was trying to make.

Heat is not a physical quantity that is added and removed, it is one form of energy that can be converted to other forms.

42 minutes ago, sethoflagos said:

Currently, you are treating the two concepts as equivalent in all your postings. 

In thermodynamics "work" and "heat" are equivalent.

I hesitate to make the claim that ALL these compressed air heat recovery industrialists are lying through their teeth.

Edited May 11, 2021 by Tom Booth

[sethoflagos]

1 hour ago, Tom Booth said:

I hesitate to make the claim that ALL these compressed air heat recovery industrialists are lying through their teeth.

I've been doing business with them for 40 years, and have no such hesitation. And not behind their backs either.

[Tom Booth]

3 minutes ago, sethoflagos said:

I've been doing business with them for 40 years, and have no such hesitation. And not behind their backs either.

Ok, well, I'm not surprised, but I would think after all these years in business, such false advertising should have caught up with them. But the fact they are still in business making the same claims, again, makes me wonder.

_____________

Returning to the freezer box.

I imagine, as the liquid water molecules "release" the "latent heat" it is not dumped into the freezer, rather it is used by the liquid H2O in the construction of it's crystal lattice. Internal molecular bonds or whatever, to form the ice.

I question exactly how much "waste heat" would actually be released.

In this respect it is, I think, worthwhile to consider the actual industrial process of gas liquefaction through an expansion turbine. The phase change draws on internal energy converted to "work" not heat transfer to the environment.

And back in the freezer, the expanding ice doing additional "work" in the process  of formation, probably requires additional heat which it draws from its surroundings.

So actually the ice box probably gets a little colder as the ice forms and simultaneously performs "work" lifting a weight.

______________

Unfortunately it seems, if I were to construct this ice bomb engine and run it, demonstrating the factuality of these hypotheses, what would be the result if I were to post my data, complete with video, visual demonstrations?

[sethoflagos]

52 minutes ago, Tom Booth said:

In this respect it is, I think, worthwhile to consider the actual industrial process of gas liquefaction through an expansion turbine. The phase change draws on internal energy converted to "work" not heat transfer to the environment.

Why do you say this?

Partial condensation within a turboexpander reduces its performance. The phase change does not produce work, it renders some of the potential work output unavailable. It is therefore undesirable, though often unavoidable in some typical applications (eg chilling and depressuring the inlet stream to a demethaniser).

You do not strengthen your posts by pretending expertise in fields where you have limited insight.

Edited May 11, 2021 by sethoflagos

[exchemist]

2 hours ago, Tom Booth said:

"Chemical potential energy" is not heat. The original ambient heat supplied has already been converted to something else entirely.

By lifting a weight in the freezer, the "chemical potential energy" is, at least in part, converted directly into mechanical energy, not heat. So in theory, less heat needs to be removed than what was originally supplied. It is removed to supply power to the load, the spring, or whatever our ratchet device is winding, converting the chemical potential energy into useable form and skipping heat release into the ice box altogether.

Perfect energy conversion is probably unobtainable. Some "waste heat" will likely be generated, necessitating removal, but it will be less heat, not more than what was previously added. Theoretically anyway.

Can we assume an extremely low efficiency for this ice formation?

That is, is a whole lot of heat being transfered?

Let's say the water warmed just enough for it to thaw is at approximately 32°F. To re-freez it needs to be cooled down to, approximately.... 32°F

As it crystalizes it performs work but remains at 32° F.

How much "HEAT" transfer is actually necessary to bring water from a 32°F liquid state to a 32° solid state?

There are other means and methods of transferring energy other than heat transfer, which is the whole point that Tesla was trying to make.

Heat is not a physical quantity that is added and removed, it is one form of energy that can be converted to other forms.

 

I do not understand what point you are trying to make here.

[Tom Booth]

3 hours ago, exchemist said:

I do not understand what point you are trying to make here.

It goes back to my statement that the "ice bomb engine" does NOT use ambient heat to do work at all.

You said: "yes it does".

My point is, no, it doesn't.

Saying the ice bomb engine uses heat to expand is like saying that my car runs on sunlight.

I'm saying: no, it runs on gasoline.

Ultimately, it can be conjectured that my car does indeed run on sunshine, and in a roundabout way this is correct, but the reality is, my car does not run on sunshine it runs on gasoline.

You can trace the potential energy all the way back to the big bang if you want, but the fact remains, practically speaking, sunlight is not the immediate primary cause that enables my car to run, the sun shining or not shining has no immediate bearing or direct influence on the operation of my car, which continues running just fine long after sunset.

The "potential energy" stored in liquid H2O is no longer HEAT any more than gasoline is actual sunshine.

You then go on:

Quote

This potential energy then flows out when the temperature is reduced

What?

If I carry a bowling ball up a hill, it "stores" potential energy, metaphorically speaking. The potential energy cannot "flow out" of my bowling ball, or anything else. Potential energy is not a substance that can be carried around like water in a bucket and poured out.

[Tom Booth]

6 hours ago, sethoflagos said:

Why do you say this?

Partial condensation within a turboexpander reduces its performance. The phase change does not produce work, it renders some of the potential work output unavailable. It is therefore undesirable, though often unavoidable in some typical applications (eg chilling and depressuring the inlet stream to a demethaniser).

You're referring to a different use case.

That's like saying the evaporator in a refrigerator is undesirable because it doesn't produce heat or pressure.

A turbo-expander when used to liquefy gases is not meant to produce work, it's meant to liquefy gases.

That it succeeds in liquefying gas does not "reduce it's performance" because it does less work. Doing work is not it's purpose.

Most turbo-expanders used for liquefaction of gas are bootstrap systems where the work output is used only to reduce the load on the compressor and the two are coupled together on the same shaft. There is no external work output. That's not it's purpose.

How can the liquefaction of gas, in a gas liquefier be "undesirable" when that is it's purpose?

Too bad that the liquefaction of gas in a gas liquefier is "sometimes unavoidable". Boy how those gas liquefier operation guys wish that they could avoid having those darn turbo-expanders goin' and liquefyin' gas all the time. How they just wish they could find some way of avoidin' that,

gosh darn it.

Quote

...in some typical applications (eg chilling and depressuring the inlet stream to a demethaniser).

I said liquefaction. Not chilling and depressurizing.

Quote

The phase change does not produce work

This is, of course true. The expenditure of energy, the work performed by the gas, to turn the turbine, results in phase change.

You have it backwards, or are referencing a different use case.

For many difficult to liquefy gases, it was found that pressurization and cooling was not enough.

A "quick and dirty" method to liquefy such gases was to first cool and compress the gas as much as possible, then in the final stage, to release the compressed gas through a turbine attached to a load. The  turbine is kept thermally isolated from the ambient environment so that the gas, as it expands through the turbine performing work is unable to absorb any heat.

Under these unusual conditions, the gas draws on INTERNAL energy in powering the turbine. The sudden loss of energy, with no way to get it back by absorbing heat from the environment results in the instantaneous condensation of the gas into a liquid within the turbine.

The process you reference is unrelated. Turbo-expanders are used in many different ways.

Quote

You do not strengthen your posts by pretending expertise in fields where you have limited insight.

Hmmm.

Since when is saying that it is "worthwhile to consider" something "pretending expertise"?

Edited May 12, 2021 by Tom Booth

[sethoflagos]

49 minutes ago, Tom Booth said:

It goes back to my statement that the "ice bomb engine" does NOT use ambient heat to do work at all.

You said: "yes it does".

I had to check back through my activity record, but I can say with confidence that I've passed no comment on the thermodynamics of your 'ice bomb' whatsoever.

I have passed comment on the thermodynamics of your Stirling engine (which extracts a percentage of the heat flow between a hot source and cold sink to create shaft work)

And also your refrigerator machine which essentially employs a compressor to lift a weight a few millimetres.

1 hour ago, Tom Booth said:

You then go on:

Quote

This potential energy then flows out when the temperature is reduced

 

What? 

This is most definitely someone else's words you're quoting.

Please try and keep track of who you are addressing, who you are quoting, and the true context of each quote. 

[Tom Booth]

55 minutes ago, sethoflagos said:

I had to check back through my activity record, but I can say with confidence that I've passed no comment on the thermodynamics of your 'ice bomb' whatsoever.

What you are referring to is my response to exchemist, 

 

Quote

 

 5 hours ago, exchemist said:

I do not understand what point you are trying to make here.

Quote

It goes back to my statement that the "ice bomb engine" does NOT use ambient heat to do work at

 

 

 

Quote

 

This is most definitely someone else's words you're quoting.

Please try and keep track of who you are addressing, who you are quoting, and the true context of each quote. 

 

Right 🙄

[sethoflagos]

12 minutes ago, Tom Booth said:

Your referring to a different use case.

That's like saying the evaporator in a refrigerator is undesirable because it doesn't produce heat or pressure.

A turbo-expander when used to liquefy gases is not meant to produce work, it's meant to liquefy gases.

That it succeeds in liquefying gas does not "reduce it's performance" because it does less work. Doing work is not it's purpose.

 

This is about as a valid a use case as calling your car a tractor to explain why its upside down in a potato field.

Turboexpanders, if they were in the slightest way relevant to your OP which they are not, are NEVER designed for the purpose you describe and to infer that they are serves no purpose other than to mislead the membership of this site. 

  

 

 

 

 

[Tom Booth]

Who I was responding to is right there in the quotation box.

How about you stop devolving the conversation into petty attempts at character assassination.

7 minutes ago, sethoflagos said:

 

Turboexpanders,... are NEVER designed for the purpose you describe and to infer that they are serves no purpose other than to mislead the membership of this site. 

If you are unfamiliar with such a use for turbo-expanders, I can provide references, if not banned from the forum before given a chance, which is usual for this juncture.

We are talking about turbo-expanders used for gas liquefaction are we not?

Quote

They are standard in the natural gas industry for liquefaction (FIG. 1)

 

http://gasprocessingnews.com/features/202006/fundamentals-of-turboexpander-design-and-operation.aspx

Edited May 12, 2021 by Tom Booth

[sethoflagos]

37 minutes ago, Tom Booth said:

How about you stop devolving the conversation into petty attempts at character assassination.

If that's how you read my posts then, I'm sorry, it was not my intent.

37 minutes ago, Tom Booth said:

If you are unfamiliar with such a use for turbo-expanders, I can provide references...

Having spent the last 22 years in the West African oilfields, I am unfortunately more familiar with such malpractices than you can possibly imagine. Unless that is you've done time with Shell Petroleum Development Company of Nigeria which would put us on a par. Using a turboexpander as a souped up J-T valve is simply something you should not be broadcasting to the world in my view. At best, people won't have a clue what you're on about, and those who do understand will assume you've worked for Shell Petroleum Development Company of Nigeria. Lose-lose.

Edited May 12, 2021 by sethoflagos

[Tom Booth]

Quote

Using a turboexpander as a souped up J-T valve is simply something you should not be broadcasting to the world in my view

What?

It's friggin' common knowledge except maybe for (some) in the industry who try to guard it like a trade secret. Which to some degree it (sort of) is. But do you read: "standard in the natural gas industry for liquefaction." not as you suggest "malpractises".

At any rate a long way from "Never".

Edited May 12, 2021 by Tom Booth

[sethoflagos]

1 minute ago, Tom Booth said:

What?

It's friggin' common knowledge except maybe for people in the industry who try to guard it like some kind of trade secret or other.

It isn't right though is it, Tom.

Right would be investing in the appropriate refrigeration system to take out the condensate cut you want in a conventional condenser. Just like the textbooks say.

Just sayin'

[Tom Booth]

14 minutes ago, sethoflagos said:

It isn't right though is it, Tom.

Right would be investing in the appropriate refrigeration system to take out the condensate cut you want in a conventional condenser. Just like the textbooks say.

Just sayin'

I don't know where you're coming from but Turbo-expanders are WIDELY used for gas liquefaction. It has practically replaced every other method there is in every industry involved in gas liquefaction all around the world.

First you try to deny it exists, apparently because it wasn't on Wikipedia from which you were apparently cp'ing, now you are trying to demonize a standard industrial process, used all around the world.

What's your game dude?

Edited May 12, 2021 by Tom Booth

[sethoflagos]

2 minutes ago, Tom Booth said:

I don't know where you're coming from but Turbo-expanders are WIDELY used for gas liquefaction. It has practically replaced every other method there is in every industry involved in gas liquefaction all around the world.

First you try to deny it exists, apparently because it wasn't on Wikipedia from which you were apparently cp'ing, now you are trying to demonize a standard industrial process, used all around the world.

What's your game dude?

Seriously?

Non-cowboy operations condition their gas in a proper gas plant with the full demethaniser, deethaniser, depropaniser and debutaniser set to maximise LPG extraction and ensure their sales gas output is fit for purpose.

Cowboy operations cherry pick a rough LPG cut with a single stage J-T or turboexpansion stage and more often than not screw up the national sales gas supply grid with intermittent slugs of condensate. 

Don't confuse typical US practice for global practice. Most of the world falls into the first of these two categories.

[Tom Booth]

Well here are a few additional references I'll be so irresponsible as to post about a non-existant process that the so-called cowboy operations can peruse for their entertainment.

https://www.laturbine.com/wp-content/uploads/2020/12/Fundamentals-TBX-GPLNG.pdf

L.A. Turbine - 28557 Industry Drive, Valencia, CA 91355 - manufactures and services turbo-expanders.

 

http://rddynamics.com/products/turboexpand.html

 

Quote

Applications:
    Air Separation Plants
    Oil and Gas Processing
    Gas Liquefaction
    Power Generation
    Cryogenic Refrigeration
    Hydrogen Economy

R&D Dynamics designs and manufactures turbo-expanders for specific applications.

https://machinery-inanutshell.blogspot.com/2014/01/Turboexpander-Performance-1.html

 

Quote

 

Turboexpander Fundamentals

Heinz P. Bloch, Claire Soares, in Turboexpanders and Process Applications, 2001

BASIC APPLICATIONS

A turboexpander generates the deep, low-temperature refrigeration industrially used for gas separation and liquefaction, and a number of related purposes.

 

https://www.sciencedirect.com/topics/engineering/expander-process

 

To conclude for now, here is a very in depth thesis in (PDF 175 pages):

"Design and Construction of Turboexpander based Nitrogen Liquefier"

It includes the entire history and historical development of all the various gas liquefaction processes with particular emphasis on turboexpanders for liquefying nitrogen.

http://ethesis.nitrkl.ac.in/6598/1/DESIGN_AND_CONSTRUCTION_OF_NITROGEN_LIQUEFIER.pdf

So much for "never designed for the purpose". the number of references available could fill a library.

A few highlights:

Quote

Organization of the thesis
The thesis has been arranged in eight chapters and appendices.

Chapter I deal with  a  general  introduction  to cryogenic  refrigeration  and liquefaction  processes. ...

Chapter II is  the literature  review  part  of  the  thesis.  It describes  history  of cryogenic liquefaction and development of  turboexpander. ...    It  also  focuses  on  the  process  design techniques, thermodynamic equations ...

Chapter III presents  process  design  of  the  turboexpander  based  nitrogen liquefaction cycles ...

Chapter V comprises  with  the  design  of  the  turboexpander.  It  consists  of  the design  of  turbine  wheel,  nozzle, diffuser, shaft, brake  compressor,  bearings  and supporting components.

Chapter VI illustrates the fabrication  of  remaining  components  used  in  the liquefier.  It  also  covers assembly  of  the  fabricated components  and  instrumentation.

Chapter VII shows testing performance of the turboexpander. It also includes operation and performance study of the liquid nitrogen plant.

Chapter VIII presents  the  concluding  remarks  and  recommendation  for  future work. And finally references are presented which utilized to develop the turboexpander based  nitrogen liquefaction  plant. It consists of appendices  which contain fabrication drawings  and  photographs  of  the  turboexpander  parts,  heat  exchanger  and  other components of the plant.

Turboexpanders have been used for the liquefaction of various gasses, (though I don't know your age), likely before you were born.

and I don't know what your supposed experience in the oil fields in Nigeria or West Africa may have been but it is a small fraction of the many applications for liquefying gases with turboexpanders.

And I'm not even talking about Petroleum. I'm talking about gases like air, hydrogen, helium, nitrogen, oxygen etc.

Edited May 12, 2021 by Tom Booth

[Tom Booth]

9 hours ago, sethoflagos said:

Turboexpanders, if they were in the slightest way relevant to your OP which they are not, are NEVER designed for the purpose you describe and to infer that they are serves no purpose other than to mislead the membership of this site. 

Hopefully the relevance is obvious to others.

It's just an example of the conversion of heat to work in a thermally controlled, heat restricted environment.

When a substance does "work" and cannot take in additional heat, from the surroundings, the work is accomplished at the expense of internal energy, which accelerates the change of state  In this case, causing the water-ice to freeze more rapidly. (Perhaps almost instantaneously, like a bottle of drinking water super-cooled in the freezer can suddenly freeze when agitated), the same way  a gas doing work in a COLD insulated turbine suddenly liquefies.

I won't get into how all this relates to my SE experiments. But anyone here familiar with that subject should be able to put 2 & 2 together.

An SE engine works by thermal compression alternating with mechanical expansion. Similar to the compression-expansion that takes place in a bootstrap turbo-expander.

Isolated from the ambient  environment. Thoroughly Insulated. Particularly on the cold expansion side. What happens?

Edited May 12, 2021 by Tom Booth

[exchemist]

11 hours ago, Tom Booth said:

It goes back to my statement that the "ice bomb engine" does NOT use ambient heat to do work at all.

You said: "yes it does".

My point is, no, it doesn't.

Saying the ice bomb engine uses heat to expand is like saying that my car runs on sunlight.

I'm saying: no, it runs on gasoline.

Ultimately, it can be conjectured that my car does indeed run on sunshine, and in a roundabout way this is correct, but the reality is, my car does not run on sunshine it runs on gasoline.

You can trace the potential energy all the way back to the big bang if you want, but the fact remains, practically speaking, sunlight is not the immediate primary cause that enables my car to run, the sun shining or not shining has no immediate bearing or direct influence on the operation of my car, which continues running just fine long after sunset.

The "potential energy" stored in liquid H2O is no longer HEAT any more than gasoline is actual sunshine.

You then go on:

What?

If I carry a bowling ball up a hill, it "stores" potential energy, metaphorically speaking. The potential energy cannot "flow out" of my bowling ball, or anything else. Potential energy is not a substance that can be carried around like water in a bucket and poured out.

Before, you stated the ice engine does not convert ambient heat into work. And I said, on the contrary, it does. I went on to explain how this conversion takes place:-

ambient heat -> chemical potential energy in liquid water ->work done in expanding the ice + heat output as Latent Heat of Fusion.

I fail to see why this is an issue.

But it appears, from your bowling ball analogy (or non-analogy), that you don't understand what I mean by chemical potential energy. Look, if two substances react chemically together with evolution of heat (what we call an "exothermic" reaction), they go from a higher energy state to a lower energy state. So we can say that the reactants have chemical potential energy, which is released and flows out as heat when they react together. That's all it means.

What happens is weaker bonds in the reactants are replaced by stronger ones in the products. Crystallisation is a similar process, in that the unbonded molecules in the liquid state become bonded in the solid, with release of heat, which we call the Latent Heat of Fusion.  So the molecules in the liquid state have chemical potential energy, relative to the solid.    

 

 

 

Edited May 12, 2021 by exchemist

[dimreepr]

17 minutes ago, Tom Booth said:

Hopefully the relevance is obvious to others.

It's just an example of the conversion of heat to work in a thermally controlled, heat restricted environment.

When a substance does "work" and cannot take in additional heat, from the surroundings, the work is accomplished at the expense of internal energy, which accelerates the change of state  In this case, causing the water-ice to freeze more rapidly. (Perhaps almost instantaneously, like a bottle of drinking water super-cooled in the freezer can suddenly freeze when agitated), the same way  a gas doing work in a COLD insulated turbine suddenly liquefies.

I won't get into how all this relates to my SE experiments. But anyone here familiar with that subject should be able to put 2 & 2 together.

An SE engine works by thermal compression alternating with mechanical expansion. Similar to the compression-expansion that takes place in a bootstrap turbo-expander.

Isolated from the ambient  environment. Thoroughly Insulated. Particularly on the cold expansion side. What happens?

Why does a pendulum never hit you on its return?

[exchemist]

I was reflecting on the ice engine today. It's quite an ingenious and entertaining idea, albeit an impractical one. The feature of it that differs from most heat engines is that it exploits the change in volume due a phase change in the working fluid, rather than the expansion on heating a gas. 

It occurred to me that this is also true of the earliest steam engines. These were "atmospheric engines", in which the power stroke exploited the reduction in pressure when the steam in the cylinder was condensed, by the injection of a cold water spray.  

So here, as in the ice engine, a power stroke is produced by a phase change, and is accompanied by a release of Latent Heat, whereas the heat input to the engine takes place on the return stroke, i.e. as the cylinder is refilled with steam.

It seems that this feature - of the heat input taking place on the return stroke -  is what is bothering @Tom Booth  Perhaps he should think about Newcomen's atmospheric engine for a bit...... 

[Tom Booth]

4 hours ago, exchemist said:

Before, you stated the ice engine does not convert ambient heat into work. And I said, on the contrary, it does. I went on to explain how this conversion takes place:-

ambient heat -> chemical potential energy in liquid water ->work done in expanding the ice + heat output as Latent Heat of Fusion.

I fail to see why this is an issue.

 

Thanks for taking the time to explain your point of view, which I don't necessarily totally disagree with.

But in the economy of energy, we have the conservation of energy: "Energy can never be created or destroyed it can only change form."

Putting that in economic tems, if I start out with US dollars and convert that to euros. I no longer have any dollars. The dollars are gone, and now I'm now carrying euros.

If I then convert the Euros to Yen, well those original dollars are nowhere to be found, so if I then convert some of those Yen into British pounds and the rest back into dollars, it wouldn't really be accurate to say that I converted my dollars into British pounds would it?

Really, have I even converted "some" of my dollars into pounds?

No, I converted my Yen into pounds.

I just think it is important when conceptualizing these things to keep in mind that HEAT is not a physical thing that "flows into" and then "flows out of" any kind of heat engine, and that energy itself is basically just an accounting.

It creates a picture in the mind where what goes in, must all be coming out the other side, but that is not the case. What went in, the ambient heat is already long gone right from the start.