The properties of Superheated steam

[millsk]

Looking at the steam tables I see that the entrolpy of steam at a constant temperature increases with a decrease in pressures.

As an example, Steam at a temperature of 1000 degrees has an entrolpy 1520 @ 500 PSI.

The same temerature steam at a pressure of 2000 PSi holds less energy, 1475.

Can anyone explain this?

 

[Mech_Engineer]

Wait, are you talking about enthalpy or entropy?!

Enthalpy is a measure of internal energy, whereas entropy is not.

 

[millsk]

ah good catch.

I ment enthalpy. The numbers reflect enthalpy, but of course they both go up.

 

[Q_Goest]

Hi millsk,
For a thermodynamically ideal gas, the internal energy is independent of pressure. Internal energy depends on temperature only.

For an ideal gas, PV = constant given any temperature.

So enthalpy, which is U + PV should be constant for an ideal gas that is also thermodynamically ideal for any given temperature as pressure is varied.

The fact enthalpy decreases slightly at higher pressure is primarily due to the way the gas molecules ‘rearrange’ themselves at the higher pressure. Note that an increase in enthalpy as you’ve noticed here is the most common deviation from ideal behavior.

 

[aviseksrkr]

my question is why only super heated steam is used for steam turbines??

 

[Feliks]

Have you seen the new steam engine?
I called him a Stephenson Second

Where he goes?

http://www.new4stroke.com/images/bigboy.wav"

Regards Andrew

 

[Feliks]

Next about 550 MW power engine project:

550 MW

Regards Andrew

 

[Detlen1]

i don't mean to wast space, but wow that's impressive

 

[Mech_Engineer]

It would be more impressive if it actually worked, or at least had a working prototype to back up the "pretty pictures."

 

[Feliks]

It would be more impressive if it actually worked, or at least had a working prototype to back up the "pretty pictures."

"pretty picture" part "How can it be in the future (first lecture) "

Cheaper, safer

Regards Andrew

But to count V is a need to remind myself theorem of calculus

 

[Mech_Engineer]

"pretty picture" part "How can it be in the future (first lecture) "

Cheaper, safer

Regards Andrew

But to count V is a need to remind myself theorem of calculus

Uh, what? :uhh: Talk in complete sentences please.

My point is "pretty pictures" mean nothing as to the merits and feasability of the design. It seems to me it will have a necessarily low compression ratio, and sealing will be more difficult than on a conventional cylindrical piston.

 

[Feliks]

Uh, what? :uhh: Talk in complete sentences please.

My point is "pretty pictures" mean nothing as to the merits and feasability of the design. It seems to me it will have a necessarily low compression ratio, and sealing will be more difficult than on a conventional cylindrical piston.

Relax, you are not in the Gallery Museum with pictures, which you describe the first impression

It is possible to include small compromise with round sometimes.
Invention of wheel was first ,it is closest our heart.

Possible mutations water cooled half rotary:
Without that leaks in driving and from deducing of water half rotate "piston" . Elastic hose only several degrees twisted.

Do not need any oil !

Seal or Teflon or lubricated with diesel fuel.

OIl = diesel fuel in this picture

I do not have to grind any 'cylinders'

Regards Andrew

 

[Feliks]

i don't mean to wast space, but wow that's impressive

Do you know of a few pipes for steam 246 atmospheres and 565 degrees Celsius with an outside diameter 356 mm to the turbine, have walls of 82 mm thickness...
And are made by drilling forgings...

Or two small bearings ...

Regards Andrew

 

[Mech_Engineer]

The point is that none of your rendered pictures prove that your design is a good one. Only an engineering design study and a proof-of-concept engine can do that.

At my work (and in engineering generally) it is common knowledge that making a "pretty picture" is easy, but doesn't mean that the results it's presenting aren't total crap. This applies to CAD design, FEA, mathematical charts, everything.

 

[Feliks]

The point is that none of your rendered pictures prove that your design is a good one. Only an engineering design study and a proof-of-concept engine can do that.

At my work (and in engineering generally) it is common knowledge that making a "pretty picture" is easy, but doesn't mean that the results it's presenting aren't total crap. This applies to CAD design, FEA, mathematical charts, everything.

Oh yes, Riccardo worked on a couple of pictures of 80 years.
But it has a good record.
It is in this case and probably will be similar.

But most important is the new image...

Now you can work on it...

Andrew

 

[Mech_Engineer]

It's like arguing with a brick wall... a brick wall that only talks in sentence fragments!

Let me ask you this- what's your engine's compression ratio? What will its volumetric flow rate be?

 

[Feliks]

It's like arguing with a brick wall... a brick wall that only talks in sentence fragments!

Let me ask you this- what's your engine's compression ratio? What will its volumetric flow rate be?

No, no arguing , it does have a friendly discussion to a new understanding of

With "cylinder" and popped...

Mutations "Long Cylinder" and 8 valve in one "cylinder"

Are You know engine named Twin Feliks ?

Andrew

 

[Mech_Engineer]

You haven't answered my question yet- what's the engine's compression ratio?

 

[Feliks]

You haven't answered my question yet- what's the engine's compression ratio?

As an engineer, mechanic, you should give in the question whether it still regards to you, an engine with an electric ignition, or the engine ignition diesel.
Because these are very different values.

Andrew

 

[Mech_Engineer]

How about both. The point I'm making is you don't have it.

 

[Feliks]

How about both. The point I'm making is you don't have it.

If you know that I don't have, why do you ask?

Besides it's not true that I not have.
Copresion ratio teortical 0 to infinity.

Andrew:tongue:

 

[Mech_Engineer]

How about this- why is this engine design better than conventional pistons?

 

[dr dodge]

can't see a single pic

dr

 

[pallidin]

Curious pics to be sure.
Would be nice to see a working prototype, or, FIRST, to perhaps have this properly computer simulated for power/efficiency numbers.
In any event nice job!

 

[john.phillip]

How about this- why is this engine design better than conventional pistons?

I might be wrong, but I could not find where Andrew stated his design was better or revolutionary. Although we all know this is not the usual way products are developed, I think he is very creative and might one day come up with something really useful, until then, at least inventing is a very good exercise to the mind.

Also we don't know him or his background. The way he dropped pictures in this thread might mean he is desperate for attention, maybe for a reason. But posting pretty pictures and asking technical questions is harmless.

 

[Feliks]

Curious pics to be sure.
Would be nice to see a working prototype, or, FIRST, to perhaps have this properly computer simulated for power/efficiency numbers.
In any event nice job!

Once to my great invention new4stroke did a working prototype. It was in the mid 80s With very competent people saw his work, only my professor with whom I did once my thesis, and three people from the institute .. The prototype cost me three years of work and little money.
Many times I tried to invite other people from foreign universities or companies. Unfortunately, no one expressed willingness to view how his work, although that certainly would be an unforgettable impression. So I see no point in performing other prototypes of my invention, because anything that does not serve, that when they occur. On the performance of these prototypes takes time and money. I gave them some day to have something to prove. But nobody wants me to testifying. so it seems to me that if I'll do it virtually, that is enough. If anyone will be interested in the truth, then you can make a prototype. The most important is really the idea and that was it. Well, sometimes it does not need to prove, for example, that water will flow in the direction of the Earth ...Also, pumping water up, the Egyptians have already been dealt, and problems are solved.

I might be wrong, but I could not find where Andrew stated his design was better or revolutionary. Although we all know this is not the usual way products are developed, I think he is very creative and might one day come up with something really useful, until then, at least inventing is a very good exercise to the mind.

Also we don't know him or his background. The way he dropped pictures in this thread might mean he is desperate for attention, maybe for a reason. But posting pretty pictures and asking technical questions is harmless.

Many thanks for keeping me in spirit, because this is not universally replaced ...
Indeed, there may not the most important figures, why this design has to be better than the traditional...

In large scale are better see advantages or disadvantages

Star engines were characterized biggest always force density.

Below picture of the star half rotate around 10 (40) with "cylinders". for the transparency of the picture one can see only 3 additional "cylinders" more than is at the animated film.
One can also see dimensions of the whole of the engine in the assumption that every cylinder has such dimensions for the picture half rotate with the set connecting rod of the Sulzer D= engine of 900 mm and stroke 2500 mm .

However 10 (40) "cylindrical" engine half rotate about the same working capacity in comparing to the Sulzer 10 engine cylindrical on the picture below .

Sulzer: 10 Cylinders 20 m long , 15 m hight , 1500 Ton weight

Half rotate star : 10(40) "Cylinders" 4,5 m diameter , 4,5 m long
about 70 ton weight.

And most importantly.. Since in the engine half rotate mass innertia are several times Sulzer smaller than in the engine, engine half rotate can work with the much greater rotation speed.
Sulzer : 102 RPM 60 000 KW

Half rotate 250 RPM 150 000 KW

In same intake work volume .

Same properties would be the size of the attachment to the steam engine steam about 50 bars.

Engine with easy water cooling all its pistons.
Without that leaks in driving and from deducing of water half rotate "piston" . Elastic hose only several degrees twisted.

And yet you must add that the engine will not require grinding of cylinders, because the seals are working only on the "piston"
For all the deformation of cylinders have much less importance and do not require as precise as the existing structures performances.

If we add that the engine can be operated completely without oil, but the Teflon seals, then we already have a full picture of where the advantages.

Best Regards Andrew

Still have a link showing the stages of formation of this engine, which may be interesting for some.
http://www.new4stroke.com/images/Possible%20mutation%20pivot.htm"

 

[russ_watters]

Thread closed for lack of content.

 

[Feliks]

Thread closed for lack of content.

New steam engine (only one) using in Big Boy locomotive,ships, tractor, or energy plant.
Possible fuel: biomass ,wood,peat, russet coal,coal,ethanol,biooils,oil,hydrogen,biogas,LPG,natural gas,uranium,fusion.
Big Boy second:

[URL]http://www.new4stroke.com/images/bigboy.wav[/URL]

Regards Andrew