Steam turbine driven turbojet

Hi Serge,
I attached a picture of the excel sheet for one of my many calculations. Note that when Fill is mentioned, it refers to the attached concept that I'm developing. Take a look at it and ask any questions.

Note that this is my latest cut for ~200 Hp machine (same as Besler's Airplane). For that matter, anyone may ask questions.



Hi Novice,
To stay on task, I just read Besler was a big boundary layer guy. He called his airplane forced circulation boiler a boundary layer breakthrough.

Here's the question, what is the boiler planned for the nuclear steam generator, i.e. mono-tube, forced circulation, natural circulation (tube boiler) or fire tube? Also, can be any combination? I'm leaning towards a combination that I think will work best.

Kind regards,
Rick

Rick-

Art Gardiner designed a steam generator for the Mark 2 Streamliner that I was planning to build after my crash, and the design he put together wasn't that much bigger than the Mark 1 generator. His design was a multiple pass generator that would put out 3000+lbs/hr, burning somewhere around 50 gph. The coil stack was less than 24 inches in diameter and though we didn't build either the generator or the streamliner, there weren't any fitment problems.

Art and I are strong proponents of using finned tubing-the economizer/evaporator section in his design was finned-which makes a lot of steam in a small package.

Ah well...next time around-maybe I'll build it!


Chuk

I only worked on one nuclear reactor, it’s basically a tank of water with the reactor rods (core) inside the tank and a bank of circulating pumps around the tank circulating the water around the core in the middle of the tank. Each pump in a separate room with valves to isolate the pump for maintenance. The water in the reactor was circulated through a heat exchanger to generator steam so radioactive water was not going to the turbine.
I would call it a forced circulation reactor. Loose the pumps, over heat the reactor, loose the state.
Rolly

Chuk,
I agree, finned economizer tubing is the way-to-go. I remember you showing me the tubing at your shop in Florida.

Also, you got me thinking ... about using condensation in the hot well being supplied by feed water heater. I estimate a temperature rise of 50 Deg F.

Attached is the new calculation w/finned tube and condensed water...up to 240 Hp. Prototype concept drawing attached. I believe the burner needs infrared to achieve best heat transfer along with a high flow burner like yours.

As you know, what is calculated needs to be tested. I will be building a scale prototype to check out my calculation. Might be used on a Bike or something that size. Then I'll make the investment into full scale. You are welcome to build your boiler also. Which ever one works best is the way to go.

Thanks,
Rick

Novice,
Rolly brings up a good point that all current nuclear reactors are PWR (pressure water reactors). You do not want transition of water to steam next to the heat rods.

At Northeaster University (Boston) I took Nuclear Engineering I and II. At that time, my class visited the MIT nuclear PWR facility. This is where the above concept was actually seen and demonstrated. If the water were to transition to steam near the generating rods, it will go into over drive and start a melt down.

The other input I have is from my good friend (Engineer) who was a Nuclear Sub Commander. I often ask how the nuclear system worked, down to some minute detail. Overall principle of operation is that it runs on saturated steam, the most inefficient system there is. Who cares, the energy is cheap and plentiful. It kind of just lolly gags around spinning a turbine and consistently produces electricity to a battery. This is hardly the system for an aircraft engine. I would classify it as a combination forced circulation system on a condensing mono-tube system.

The quest to my query is to see what other concepts were proposed to see if there is something I'm not thinking of pertaining to making a new stellar boiler system.

As always, kind regards,
Rick

The Soviet Era Kirov Class nuclear battle cruisers had a CONAS propulsion system -- COmbined Nuclear And Steam. Basically, the nuclear reactors drove steam turbines, but there were backup boilers in place. This might indicate that Soviet nuclear power was not up to US standards. On the other hand, two alternative uses for the boilers have been suggested and I haven't been able to find a definitive source as to how these played out. One suggestion was that the nuclear plants were for cruising and that the boilers could be fired up in parallel with the reactors only when needed for fast sprints -- thus obviating the need to design a larger nuclear plant for the larger battlecruiser hull. The alternative theory was that the boilers had excess superheater capacity and were capable of also superheating reactor steam, improving system efficiency and output when demand arose. The second idea isn't bad, a fuel oil fired superheater needn't be all that heavy and would consume a relatively small amount of fuel. In an aircraft, it could be fired up for takeoff or other instances when the added power derived from higher efficiency would be beneficial -- the added weight of superheater and fuel would certainly be much less than a PWR with the same peak capacity.

Serge,
I wanted to get back to you about the BTU and Horsepower calculator posted above. If you would like the Excel version, I'll be happy to send it to you?

Any other requests are welcome along with an explanation as to how it works. It is based on the steam boat fellows who have estimated the square foot of a type of boiler; mono tube, fire tube and multi-tube to produce boiler horsepower.

Rick

Also, Chuk,

I performed a calculation on your LSR boiler as a reference. Pretty sure you're at 200 Hp to meet the record you hold (Steam Piston Speed Record).

Rick.H Wrote:
-------------------------------------------------------

>
> Hi Novice,
> To stay on task, I just read Besler was a big
> boundary layer guy. He called his airplane forced
> circulation boiler a boundary layer breakthrough.
>
> Here's the question, what is the boiler planned
> for the nuclear steam generator, i.e. mono-tube,
> forced circulation, natural circulation (tube
> boiler) or fire tube? Also, can be any
> combination? I'm leaning towards a combination
> that I think will work best.
>
> Kind regards,
> Rick

At supercritical pressures water does not boil, just expands in volume with increasing temperatures.
Aircraft had 450MW water heater that was designed as 11 feet stainless steel sphere with just 2.5 feet diameter heating core having hundreds of parallel water channels. Water was pressurized to almost 5500psi and heated to 1000F. Generator was very heavy. Water alone was over 20 tons.


Besler's 4 engines steam aircraft was indeed very interesting.
In his report he was a proponent of his own steam engine, but also did not completely exclude a future development of a compact high efficiency steam turbines of moderate power 150hp and more.
Aircraft project had steam condensers but they did not have any cooling fans. So they were useless at takeoff and there was a significant loss of water.

Small steam turbines have less net efficiency than steam engines with the same steam parameters. Besler steam aircraft engine could only at maximum temperatures 700-720F due to lubrication oil turning into hard deposits on cylinder wall and piston rings. Steam turbine rotor made of modern chromium nickel steel can work thousands of hours at 1200F. With the internal cooling this temperature can be boosted up to 1500F.



Edited 2 time(s). Last edit at 12/10/2020 08:08AM by novice.

(At supercritical pressures water does not boil, just expands in volume with increasing temperatures.)

Not true.

All water in a boiler boils, there is always space above the water where the steam cushions the expansion creating pressure.

If there were no steam and space the water would hydraulic and burst the pressure vessel with almost no heat, as water expands in volume very fast when heated.

Rolly

Hi Novice,
Again, I enjoy this thread.

I see some real genius with Belsler regarding the Aircraft Steam Engine. I'm going to take a shot understanding his thinking on boundary layer theory. His secret paper to the US government identifies his boundary layer theory and really is talking about convective heat transfer. In order to achieve the highest convective heat transfer, he resolved to have a forced circulation boiler. This method would include a separator drum or tube.

I'm going to get a little technical here. I believe Besler understood the importance of Reynolds Number (Re). Re is indicative of turbulent flow in a system. Re is representative of fluid velocity, density and tube diameter over viscosity. Let it be known that the engineering and scientific community does not understand, at least in a theoretical sense how the boundary layer reacts at high Re numbers. High Re numbers is turbulent flow and by observation, produces exponential values of heat transfer coefficient.

The basic heat transfer equation is q = Hc(T1 - T2). Here is the challenge in a turbulent flow...what is the Hc?

I think Besler went through the same exercise that I'm describing here. The attempt at getting a heat transfer coefficient includes using the Nusselt number with the Re to determine the Hc. To complicate things, it is a differential representation of dx/dt. I tried this calculation using sections of 10 ft tubing and sequentially increased temperature as the water progressed through. Then used different heat transfer coefficients to estimate the water and steam at the various temperatures.

Long story short...it's a bust. I even did a presentation at a SACA meet to present this. I asked for help from the audience...again, a bust.

Besler probably came up short also. However, when you want to develop a concept, you just need to experiment and record results. So here is what he did. He took an assumption on a generator tube square footage and applied a circulation pump to and from a separator tube. His results are stellar by witness of a steam aircraft that can fly. He knew that the water velocity in the generating tube needed to be maximized to gain the most heat transfer. The higher the Re, the higher the heat transfer. One more added acceleration factor. He knew the the gain in fluid velocity has an exponential effect on temperature gain.

Note that this is why a steam blower works so well. It increases steam pressure while expiring pressure in the blower.

So in summary, Besler produced a viable boiler, light enough to go in an aircraft and produce enough power to over come drag. What a wonderful accomplishment.

Great food for thought...

Kind regards,
Rick

I wanted to add to this thought and relate it to the Model Boat speed record and the mono-tube boiler that powered it. The Reynolds number is very high. In other words, the flow through the small copper tubing is very turbulent. Also, the flow velocity is very fast for a little tube.

Gentle reminder: higher the turbulent flow, the greater the convective heat transfer. This relationship is exponential.

Model Boat Steam Speed Record

Let us talk water rates as another topic and sometimes miss understood. I'll use a water rate of 10 gallons/hr. You can achieve this rate with 1/2" pipe or 3/8" tube...which is better? If I asked Besler which one, you guessed it, he would say the 3/8" tube. The flow velocity is far greater in the smaller diameter tube.

On the flip side, it becomes counter productive on efficiency of the system with huge pumps to produce high flow velocity.

efficiency = work out / (heat in + pump work)

Besler's aircraft engine used both a feed pump and forced circulation pump. This no doubt lowered the overall efficiency of this steam powerplant. However, results are stellar.

Chuk and I had a nice conversation at the dinner table one SACA meet with pencils in hand and drawing all over the table clothe at a restaurant (paper of course). We discussed how important it is to continuously increase the diameter of the generating tubes. Reason is to reduce the push back of the water/stream on the feed and circulating pumps. What's the reason for a steam generator tube when a pump has to produce the same pressure as what you get out of the system. At the time, we were discussing a forced and an Inductor jet (French) circulation design made with pancake wound pipe.

Boundary layer diagram (left side is laminar flow, right side is turbulent) and PT 6 concept attached.

Again, food for thought.

Laminar verses turbulent flow in more relevant to the flow of gasses thorough the tubing bank after leaving the combustion chamber. Raytheon in there extensive study on cooling radar tubes found that turbulent flow of gases around pipe or tube did four times more work then Laminar flow of gases. Heat radiates in all direction at the same speed of light in the combustion chamber. Wrapping the combustion chamber with the appropriate size pipe with cool feed water has the highest differential in temperature, and does more work then any other location in a boiler or steam generator. From the combustion chamber the hot gases flow in either laminar flow or turbulent flow based on the tube layout and winding configuration. The winding pattern in a wound coil generator should be wound so the gases flow through the bank in a turbulent pattern to achieve the highest output of a coiled generator, reducing the overall size of the tube bank and size of the generator.

Rolly

Good point Rolly,

On a steam locomotive and on some Stanley Cars, they incorporated a Steam Blower. This uses the steam from the boiler to draw the hot gases through the boiler fire tubes. I use a steam blower on my Steam Scooter.

Here is the concept that sometimes is hard to grasp. Even when the system expires steam and the pressure should be going down, what actually happens is the pressure rises. This is because the increased combustion gas flow through the fire tubes is more turbulent and has an exponential effect on convective heat transfer.

Same effect on generating tubes...same principle.

Rick

Laminar verses turbulent flow

Actually a firetube boiler the combustion gases are going through the tubes in a laminar flow, and because of the shape of the tube being rolled in at the tube sheet more or less a sharp edge this acts as a very poor venturi entrance. The gasses tend to confine themselves to the center of the tube and increase in speed as they travel up the tube.
They only work because the heat in gases of the flue tube also radiates in all directions.
Years ago some of the members in SACA-NE did a study on how much heat was lost, actually how much work was actually doing any work. It was found only the first three inches from the bottom tube sheet did any work. A lot was being done by the tube sheet itself.

To increase the heat transfer rate the venturi mouth would have to be a larger radius allowing much more gas in the tube. This would move the hot gases closer to the wall of the tube. It would also eliminate the number to tubes in the plate nullifying the change.

Rolly

Steam boiler is heated with a high temperature gases. Combustion process can be greatly intensified by turbocharging.
[steamautomobile.com] - German WWII design of the steam turbine
aircraft with the turbocharged steam boilers.
In USA Nathan Price proposed turbocharged steam generator with weight of 1800 lbs producing steam for 5000 hp aircraft steam turbine.

All steam aircraft projects failed because inventors forgot to design air cooled steam condensers. Without condenser steam powerplant has low efficiency and very high water loss.
The best works on automotive steam condensers were done in 1970s. These condensers were very efficient and relatively lightweight due to all aluminum design. With small modifications they can be installed into aircraft wings or fuselage:

[nepis.epa.gov]

A nice article about mono-tubes as considered as a flash boiler.

Flying Steam Engines

This article talks about the key element to steam generation is the velocity of the water through the tubes.

Chuk,
Hope you are listening...about that Art Gardner Design, I'm very interested!

Rick-

Art Gardiner designed a steam generator for the Mark 2 Streamliner that I was planning to build after my crash, and the design he put together wasn't that much bigger than the Mark 1 generator. His design was a multiple pass generator that would put out 3000+lbs/hr, burning somewhere around 50 gph. The coil stack was less than 24 inches in diameter and though we didn't build either the generator or the streamliner, there weren't any fitment problems.

Art and I are strong proponents of using finned tubing-the economizer/evaporator section in his design was finned-which makes a lot of steam in a small package.

Ah well...next time around-maybe I'll build it!


Chuk

From Doble Book (Jim Crank), the best boiler in the Model F put out 2,860 lb/hr. He did this in 105 - 110 Sq-ft. The generation rate 26 lb/ft^2-hr. A couple of other points of reference I've been researching:

Doble - 2,860 lb/hr, 26 lb/ft^2-hr, 110 ft^2
Serpollet - 1,000 lb/hr, 17 lb/ft^2-hr, 58 ft^2
Model Boat - 60 lb/hr, 163 lb/ft^2-hr, 11 ft of tube!

Is Art available? How is he doing? I would like to send him a paper to verify some ideas I have to achieve a high generation rate in a short amount of tube.

Novice,
Hope you're listening...any other research available to show breakthrough heat transfer in boundary layer theory?

So here's the goal: Produce ~163 lb/ft^2-hr in ~50 ft^2 of tube to achieve a steam rate of 3,000 lb/hr. By the way, I would estimate a 3,000 lb/hr machine to be a GOBLER @ 250 - 300 Hp engine @ 700 X 700 (psi,Deg F).

I'm going to offer this diagram one more time to show an idea to achieve the 163 lb/ft^2-hr.

Hope this is interesting,

Kind regards,
Rick H

Hi Novice,
Hope you're doing alright?

In performing some research, I came across this article.
Convective Heat Transfer
In this article, Table 1 provides some typical values of heat transfer coefficient. This is relative to the Flow Type as defined as convective and in particular the forced convection flow over water in a pipe. I took three of these values and plotted them on a graph. Then I best fit a curve to represent these the function. Curve is attached for viewing. Note that you'll see the other diagram in the article also.

What I was after is the relationship between forced convection (burner hot gas flow) as it relates to heat transfer. Here is what I interpret as to what is going on. As you can see on the graph, the equation is y=f(x)^~5. In laymen's terms, the heat transfer goes up exponentially with increased convective flow. It just doesn't go up to a square, it goes up nearly approaching the 5th power. This is huge.

Therefore, I really think there is some synergy with this concept to an aircraft engine. The ram air to a burner and resulting in high flow, convective gas, is an excellent match. My guess is that Besler used this to their advantage in the design of the steam powered Travel Air aircraft.

This was the reasoning for the turbine forced exhaust on the latest Doble car to improve the output of the generating coil.

The concept also repeats in the release of heat or taking heat away from a tube. Hence a condenser will operate significantly better with high velocity of flow across it's fin/tubes. Perhaps this was not considered in the design?

Last consideration and you presented a TS diagram of the Mark II design. It shows super high Entropy in the super heat of the steam. The Mark II is considering a machine at 1500 X 1250 (psi - degree F respectfully). It also states an expander without specifics. My opinion, the only expander that can handle those conditions is a Turbine. This is as opposed to a recipe type expander. Even in these conditions, the turbine blades or buckets will require Electron Beam Vapor Deposition (EBVD) of a high temp metal to withstand these conditions. Same treatment used on today's aircraft turbine engines.

Kind regards,
Rick

The draft booster on later Doble cars was no different, in principle, than the turbocharger on my last two cars. It wasn't there to improve heat transfer, for the simple reason that the Doble boilers already had excellent overall efficiency. Once you reach a certain point, there just isn't much of anywhere else to go. The turbine was there to force extra fuel and air into the combustion chamber when the demand arose.



Edited 1 time(s). Last edit at 02/23/2021 12:31PM by frustrated.

In all automobiles the air fan is installed behind the radiator(s). All of the steam condensing locomotives also had the same operation of the cooling fans.
In most of the steam aircraft projects the fan or air blower was in front of the condenser. That was necessary for downsizing the air cooled steam condenser dimensions and its air pressure drop.

There is a lot to be learned from locomotives. With regards to a noncondensing steam locomotive and in the early 1900's yielded some interesting discoveries regarding the effect of quickened exhaust. There was a device with Petticoat in its name that greatly improved the performance of the locomotive.
Steam Exhaust
Now the condensing steam locomotive used the steam exhaust to power the blower or forced air cooling as Novice spoke of. The African Locomotive used this device at the bottom of the attached link.
Condensing Locomotive
The condensing locomotives were real dogs from what I've read. They take away the petticoat effect in the noncondensing versions that gave stellar performance.

Back to Doble, he saw the issue with condensing systems, their poor performance and knew to apply the steam exhaust energy to increasing the burning exhaust flow over the generating coils. As Novice points out, this is the favorable pressure drop with resultant temperature drop. I don't think that it worked like a automobile turbo charger exactly. I could be corrected and would like to see objective evidence.

I often wondered why Dave Nerggard applied a similar device to his Stanley for driving the cooling fan. I guess he needed more water range. My thoughts were to apply that steam turbine device to power a drawing device, fan if I may, to the burning exhaust flow. This would have increased his boiler performance significantly. Oh well, it depends what your after...

There has always been something that troubles me

That is that the convective heat transfer and the boundary layer effect is really tedious and challenging to predict mathematically and therefore design systems.

When I have shown that radiant heat transfer and the resultant boundary layer effect would be breakthrough...at least in a theoretical sense. I have an article coming out in the SACA Bulletine on converting Blue Flame to Red, look for it please.

Radiant Heat Transfer

Yet I don't see significant evidence in history with Locomotives, Steam Cars or stationary Steam systems. Perhaps there is a fundamental realization that a Steam Locomotive, i.e. would burn coal and the resultant energy emitted is really in the Infrared light spectrum. Also, black iron is a wonderful absorber and emitter of infrared energy. Perhaps these are things we often overlook. However, my limited knowledge of steam history does not reveal much in the lines of Red flames. Please correct me if I'm wrong? Note that I'm always endevoring to gain knowledge in Steam (it's my passion).

Quote
Rick H
From Doble Book (Jim Crank), the best boiler in the Model F put out 2,860 lb/hr. He did this in 105 - 110 Sq-ft. The generation rate 26 lb/ft^2-hr. A couple of other points of reference I've been researching:

Doble - 2,860 lb/hr, 26 lb/ft^2-hr, 110 ft^2
Serpollet - 1,000 lb/hr, 17 lb/ft^2-hr, 58 ft^2
Model Boat - 60 lb/hr, 163 lb/ft^2-hr, 11 ft of tube!

Is Art available? How is he doing? I would like to send him a paper to verify some ideas I have to achieve a high generation rate in a short amount of tube.

Novice,
Hope you're listening...any other research available to show breakthrough heat transfer in boundary layer theory?

So here's the goal: Produce ~163 lb/ft^2-hr in ~50 ft^2 of tube to achieve a steam rate of 3,000 lb/hr. By the way, I would estimate a 3,000 lb/hr machine to be a GOBLER @ 250 - 300 Hp engine @ 700 X 700 (psi,Deg F).

Here is an interesting observation to be made about this information. The model boat numbers are associated with the model Hydroplane Tethered Boats that are popular in England. Let's do a quick calculation...
Doble: 2,860 lb/hr / Model Boat 60 lb/hr = ~48 Model Boat/Doble

When I perform this simple math and calculation another proven speed record comes to mind...you guessed it, the Land Speed Record held by the British. The steam generation is by twelve (12) suitcase sized boilers. This proves a theory I had a long time ago, at least 10 years or so.

Sorry, I didn't have time to finish the 10 year old thoughts...

Most steam engine, Rankine System, designers and builders think one (1) boiler and to get more output, make it bigger. I myself thought to add tube length with increasing diameter size would be better. Until research and perhaps a better understanding of boundary layer, convective and radiant heat transfer; I'm changing my mind.

The British Inspiration Team (Boiler Designers) no doubt put the Hydroplane Model Boat (record speeds) boiler in use with multiple boilers to achieve excellent steam generation and output. This was the spark that created the twelve (12) suitcase sized boilers leading to the land speed record (I'm quite confident in this speculation).

I call my Scooter Boiler the Clam. Right...let's steam the Clam! The Cherry Stone shape on the top of the spiral, fire tube boiler is intended to be an air heat exchanger for air preheating. I have a patent disclosure on this. However, I did not get it working to my claims. To many other problems just getting everything to work and learning from my mistakes...didn't happen.

The thought is that once you have a stellar performing boiler, do you make it bigger? No, I would now recommend multiply it. Pressure is like voltage as a sound analogy. To put multiple boilers in parallel would maximize pressure. Pressure is expander speed. The results would be good!

The other thought often overlooked is that you need to re-figure how to wind coils, create new jigs for welding and what not when going for a bigger boiler. Finding new materials, how to work with them and different welding techniques can be challenging. I made three (3) of my Clam Boilers and can produce a fourth relatively easy.

My Clam is designed and comes fairly close to be one (1) horsepower. To go for a twin Clam would get me confidently to two (2) Hp.

Hope this is interesting,

Kind regards,
Rick

Hi Novice,
Something new to think about...why condense the steam?

How about using Mechanical Vapor Compression (MVC) or recompression (MVR)? There is a catch to using MVR. First, refresh what this system is as applied to locomotives.

Holcroft-Anderson Recompressive Engine

This principle, I think, can be best implimented in a Steam Turbine Aircraft Engine. The vapor compressor would be shaft driven off the turbine shaft very similar to the gas turbine engine. Also, the geometry in an Aircraft style engine is conducive to MVR.

Keep in mind the equation PV=nRT. This is key to the catch I mentioned above. More to come...

Kind regards,
Rick

Strangely enough, over the weekend a friend bought up vapor-recompression and I had to refresh my memory.

It should be remembered that the Anderson-McCallum vapor compression system does not do away with the need to cool and condense exhaust steam -- it is simply that you do not condense all the steam. They call the unit a "cooler" instead of a "condenser", but a rose by any other name will smell as sweet...

One account said that approximately 2/3 of the exhaust, by weight, had to be condensed. Of course, the remaining steam possesses significantly greater volume.

All of this makes sense -- anyone doing extensive calculations on the operation of a uniflow steam engine realizes that the remnant steam in the cylinder does not condense when compressed but, rather, can obtain a degree of superheat greater than when it first entered the cylinder.

There is also some question as to just how valuable the approach is for use in more advanced steam systems running at higher pressures. From the Museum of Retro Technology Holcroft I take the following quote:

It should be said that Mechanical Vapour Recompression, as it is called today, is a perfectly sound thermodynamic process. If you need some steam at modest pressure, it is often more economic to compress the exhaust vapour and re-use it rather than generate more steam at high pressure in the boiler. Today this recompression is done either by steam-powered ejectors or electrically driven centrifugal compressors, usually to provide process steam.

A locomotive converted to use the process was delivered to the Southern Railway (UK) in 1930. Steam was raised in the boiler, passed through the cylinders and then, via grease-separators, to evaporative coolers either side of the engine, part-filled with water from the tender; the steam arising from this was piped to the chimney. The steam in the cooler pipes was only partly condensed, but greatly increased in density, it was recompressed by compressors driven by vertical steam engines each side of the firebox, and re-entered the boiler via clack boxes either side of the steam dome. These engines also drove gear-type pumps that brought water from the tender for the coolers and boiler make-up. A valve allowed conventional working with the cylinder exhaust going through a blast-pipe; this was used for starting.

Anyhow, attached find a basic schematic for vapor compression showing the layout, including the cooler. Also find 4 patents pertinent to the process.

Regards,

Ken

There are steam turbines that work without steam condensation- backpressure turbines. Problem with mechanical steam compression is much higher energy loss and larger dimensions of the steam compressor in comparison with condensate pump.

In theory, closed cycle aircraft propulsion is possible with steam turbine, gas turbine or Stirling engine.
The problem of all these systems is the air side of the heat exchanger/condenser. The higher are the efficiency of the chosen cycle and temperature in heat exchanger/condenser, the smaller are the dimensions and weight of the air radiator.

Some of the steam jet aircraft projects were calculated for the steam condensation at more than 500F to decrease radiator size and accelerate jet exhaust.

Your Rankine efficiency would really suck if you condensed at greater than 500F. That might not make to big a difference if you have nuclear power, and can package the reactor in a fairly lightweight incarnation. As far as an engine burning fuel goes, this is a very big hit. Come to think of it, you get a double whammy because the latent heat of vaporization is now higher and you have to reject more BTU to the atmosphere for every pound of steam used.

Ya gotta love a gas turbine with a 20:1 compression ratio, and a high-bypass turbofan.

Example from previous pages of this topic:







Altitude - 45000 ft
Aircraft speed - Mach 0.9 =594 mph
Steam input - 1200F/10000 psi
Steam exhaust - 553 F/800 psi
Steam condensation at 518 F

Specific heat consumption of this steam turbojet engine is 5.3 btu per second per 1 lbs of engine thrust. This is equivalent of 5.59 kW of thermal energy per 1 lbs of engine thrust. 1 lbs of thrust at 594 mph is equvalent of 1.18 kW of useful mechanical work.
Net efficiency of this system = 100%x(1.18/5.59)=21.1%.

This is the same as net efficiency of turbojets aircrafts
F86-Sabre:

[en.m.wikipedia.org]
[en.m.wikipedia.org]

[en.m.wikipedia.org]

1 lbs of jet fuel is equivalent of 5.44 kWh
Jet fuel consumption of this engine is 1.014 lbs per hour per 1 lbs of thrust.

[en.m.wikipedia.org]

1 lbs of jet fuel equivalent is 5.44 kWh. F86 aircraft jet engine energy consumption is 5.52 kWh per 1 lbs of thrust.

Such high efficiency of the steam turbine turbojet is possible because waste energy of steam condensation is heating the exhaust air stream and its has higher velocity.

I had a DOD secret clearance at Teledyne CAE. This info isn't clasified …I believe. On the Tacid Rainbow Gas Turbine Engine and as the Test Engineer, I saw 600 PSIG at the combustor. The situation is a common stationary test cell and not being flown through the altitude chamber. Pretty sure I cannot talk about those figures.

This type of compressor (sys) was taking atmospheric air and introducing it to the combustor at ~600 psi. This is encouraging information for MVR.

OK...next question. Do we need to run the exhaust steam to a condensor? My thought is to run the exhaust steam through a re-heater. This is very similar to what you do with a compound engine to improve efficiency. I could not find any examples of this principle with power plants or what not. ??

PV=nRT ... This is the Ideal Gas Law and can be applied to Steam.

If you keep nR as constants. Then increase Temperature (T). On the other side of the equation, perform MVR to decrease Volume (V). You get higher Pressure (P). This will balance the equation...right. This is the trick that I referred to above. If one combined the compressor stated above with Reheat, you theoretically can achieve MVR at a Super Critical state. Wow...what a concept.

Easier said than done. Why isn't this being done now? Good question right. The compressor(s) mentioned above were made out of a cast SS to shape. To perform the work that we are talking here, the material needs to be a Hastalloy X or Inconnel 718 material (both are able to be cast). Not a cheap process by-the-way.

The Holcroft Steam Locomotive does prove the concept for improving efficiency using manufacturing abilities and materials at that time. This is a wonderful thing. However, we're only talking MVR to ~200 psi. Not confident that this will be a good performing aircraft engine. Perhaps there is a balance that will work...this is food for thought. Maybe just use a separator drum/tube without feedwater heating.

Frustrated posted on this Forum in 2008 about this very subject. Sorry, not able to re-find the link to provide for convenience.

Novice, you posted this year or so ago ... Steam locomotive and aircraft engine...

Novice: your post was in my mind to this day, trying to see, thinking, if my idea was valid. I risk putting it out there when I cannot find any examples in service or even prototypes. In my job, I'm big on design verification and validation. Don't forget, I can make an Elephant Fly using Solid Works. I think one can see my quandary.

Cheers,

All files from this thread

File Name	File Size		Posted by	Date
steam turbojet.jpg	99.2 KB	open | download	novice	12/01/2018	Read message
steam turbofan.jpg	52 KB	open | download	novice	12/01/2018	Read message
steam turbojet.png	248.1 KB	open | download	novice	12/01/2018	Read message
0010.jpg	64 KB	open | download	novice	12/01/2018	Read message
0020.jpg	96.8 KB	open | download	novice	12/01/2018	Read message
0030.jpg	110.5 KB	open | download	novice	12/01/2018	Read message
steam turbine aircraft.jpg	135.7 KB	open | download	novice	12/01/2018	Read message
compressor jet calculation 1.jpg	69.7 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 2.jpg	71.1 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 3.jpg	79.4 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 4.jpg	73.1 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 5.jpg	77.2 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 6.jpg	96.7 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 7.jpg	97.3 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 0.jpg	821 KB	open | download	novice	01/02/2019	Read message
compressor jet calculation 8.jpg	44.1 KB	open | download	novice	01/02/2019	Read message
compressor jet diagram.jpg	70.5 KB	open | download	novice	01/02/2019	Read message
Turbo Fan Concept reduced.jpg	870.5 KB	open | download	Rick.H	01/04/2019	Read message
180 hp steam aircraft engine 1.jpg	193 KB	open | download	novice	01/04/2019	Read message
180 hp steam aircraft engine 2.jpg	196.7 KB	open | download	novice	01/04/2019	Read message
3000 hp Steam Aircraft Turbine.jpg	152.6 KB	open | download	novice	01/04/2019	Read message
Steam turbofan patent .png	274.6 KB	open | download	novice	01/04/2019	Read message
compressor_jet.jpg	882 KB	open | download	novice	01/06/2019	Read message
Steam turboprop racing aircraft.jpg	324.6 KB	open | download	novice	01/06/2019	Read message
Besler 4 steam engines 1.jpg	46.4 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 2.jpg	45.5 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 4.jpg	91 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 5.jpg	39.1 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 6.jpg	39.1 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 7.jpg	46.8 KB	open | download	novice	05/15/2019	Read message
Besler 4 steam engines 8.jpg	41.4 KB	open | download	novice	05/15/2019	Read message
Charcoal woodgas aircraft 1939.jpg	180.5 KB	open | download	novice	05/17/2019	Read message
IMG_20151126_203604896 reduced.jpg	318.8 KB	open | download	Rick.H	05/20/2019	Read message
IMG_1398.JPG	134.9 KB	open | download	Rick.H	05/20/2019	Read message
Mono tube-water tube Concept reduced.jpg	763.9 KB	open | download	Rick.H	05/20/2019	Read message
Mono tube-water tube Topview reduced.jpg	487.6 KB	open | download	Rick.H	05/20/2019	Read message
Casing and Coil.jpg	317.5 KB	open | download	lohring	05/23/2019	Read message
Completed Generator.jpg	168.6 KB	open | download	lohring	05/23/2019	Read message
Horizontal Boiler Pancake concept #1 reduced.jpg	561.5 KB	open | download	Rick.H	05/30/2019	Read message
Horizontal Boiler 1st Pancake concept #2 reduced.jpg	870.5 KB	open | download	Rick.H	05/30/2019	Read message
Horizontal Boiler Pancake concept #2 reduced.jpg	612.6 KB	open | download	Rick.H	05/30/2019	Read message
IMG_1438.JPG	132.3 KB	open | download	Rick.H	05/30/2019	Read message
IMG_1439.JPG	136.3 KB	open | download	Rick.H	05/30/2019	Read message
IMG_1467.JPG	125.3 KB	open | download	Rick.H	05/30/2019	Read message
Injector-Inductor Pump.png	15.9 KB	open | download	Rick.H	05/30/2019	Read message
69 - Boiler Concept reduced.jpg	703.9 KB	open | download	Rick.H	05/30/2019	Read message
65 - Radiation Heating.jpg	117.1 KB	open | download	Rick.H	05/30/2019	Read message
68 - Image (2).jpg	685 KB	open | download	Rick.H	05/30/2019	Read message
Tube Stages.jpg	252.4 KB	open | download	Rick.H	05/30/2019	Read message
Mono tube-water tube Concept reduced.jpg	763.9 KB	open | download	Rick.H	05/30/2019	Read message
Mono tube-water tube Topview reduced.jpg	487.6 KB	open | download	Rick.H	05/30/2019	Read message
Campini thermojet aircraft.jpg	222 KB	open | download	novice	06/10/2019	Read message
Steam turbojet engine parameters.jpg	821 KB	open | download	novice	06/21/2019	Read message
Water%20thermal%20conductivity%20F.jpg	126 KB	open | download	Rick.H	07/17/2019	Read message
IMG_0952 reduced.jpg	775.3 KB	open | download	Rick.H	07/17/2019	Read message
IMG_20151126_203435191 reduced.jpg	973.9 KB	open | download	Rick.H	07/17/2019	Read message
Steam Turboprop Aircraft Powerplant.png	165.4 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Condenser Design.png	116.6 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Net Power.png	112.1 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Calculation Example.png	93.3 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Cooling Fan Efficiency.png	111.7 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Condensers Comparison.png	109.7 KB	open | download	novice	08/07/2019	Read message
Steam Aircraft Condenser Pressure.png	114.5 KB	open | download	novice	08/07/2019	Read message
2019 Fall SACA Presentation.xlsx	11.2 KB	open | download	Rick.H	08/27/2019	Read message
water_density_F.jpg	116.8 KB	open | download	Rick.H	08/27/2019	Read message
Boundary Layer Concept reduced.jpg	609 KB	open | download	Rick.H	08/27/2019	Read message
Aircraft steam generator.jpg	904.2 KB	open | download	novice	08/16/2020	Read message
zsdw__capture_004_17.jpg	24.8 KB	open | download	kyleborg	08/17/2020	Read message
SBB-Image1.png	147.8 KB	open | download	kyleborg	08/19/2020	Read message
SBB-Image2.png	310.7 KB	open | download	kyleborg	08/19/2020	Read message
SBB-Image3.png	631.8 KB	open | download	kyleborg	08/19/2020	Read message
US2159758-drawing.png	137.8 KB	open | download	novice	09/23/2020	Read message
DE_336702_Steam air boat.png	74.7 KB	open | download	novice	10/01/2020	Read message
DE_438028_steam powered helicopter.png	59.2 KB	open | download	novice	10/01/2020	Read message
DE_424170_steam turbine propeller locomotive.png	118.5 KB	open | download	novice	10/01/2020	Read message
CH_94595_1500 Hp aircraft steam turbine drive.png	83.9 KB	open | download	novice	10/01/2020	Read message
DE_347009_1500Hp steam turbine aircraft.png	93.2 KB	open | download	novice	10/01/2020	Read message
Turbo Fan Concept reduced.jpg	870.5 KB	open | download	Rick.H	11/12/2020	Read message
P1010001.JPG	61.1 KB	open | download	Rolly	11/12/2020	Read message
P1010004.JPG	93.6 KB	open | download	Rolly	11/12/2020	Read message
Steam turbofan patent .png	274.6 KB	open | download	novice	11/12/2020	Read message
Steam Turboprop Aircraft Powerplant.png	165.4 KB	open | download	novice	11/12/2020	Read message
US4333309-2.png	97.6 KB	open | download	novice	11/12/2020	Read message
US4333309-8.png	105.3 KB	open | download	novice	11/12/2020	Read message
Steam engine temperature.png	105.8 KB	open | download	novice	11/12/2020	Read message
Steam turbine jet aircraft.jpg	442.1 KB	open | download	novice	11/12/2020	Read message
Formula S Racecar Desc reduced.jpg	692.6 KB	open | download	Rick.H	11/15/2020	Read message
Turbo Prop Concepts reduced.jpg	1020.6 KB	open | download	Rick.H	11/15/2020	Read message
Lear Formula Race Car.jpg	196.2 KB	open | download	Rick.H	11/15/2020	Read message
Turbo Fan Concept explained reduced.jpg	921.8 KB	open | download	Rick.H	11/15/2020	Read message
North American P-51 Mustang _ Specs, Comparisons, Images.html	103.9 KB	open | download	Rick.H	11/15/2020	Read message
CH_94595_1500 Hp aircraft steam turbine drive.png	83.9 KB	open | download	novice	11/15/2020	Read message
DE_347009_1500Hp steam turbine aircraft.png	93.2 KB	open | download	novice	11/15/2020	Read message
DE_336702_Steam air boat.png	74.7 KB	open | download	novice	11/15/2020	Read message
DE_424170_steam turbine propeller locomotive.png	118.5 KB	open | download	novice	11/15/2020	Read message
Steam turbine aircraft condenser1.png	72.8 KB	open | download	novice	11/15/2020	Read message
car2.png	131.4 KB	open | download	novice	11/15/2020	Read message
car3.png	88.5 KB	open | download	novice	11/15/2020	Read message
Condensing Steam Engine Cycle.png	388 KB	open | download	Rick.H	11/16/2020	Read message
CaseSteamTractor reduced.jpg	981.8 KB	open | download	Rick.H	11/16/2020	Read message
735 Color Piping Diagram.jpg	500.2 KB	open | download	Rick.H	11/16/2020	Read message
lsr-07-2.jpg	40.4 KB	open | download	Rolly	11/19/2020	Read message
lsr-07-4.jpg	38.5 KB	open | download	Rolly	11/19/2020	Read message
16 inch turbine - 1.JPG	67.2 KB	open | download	Rolly	11/20/2020	Read message
16 inch turbine - 2.JPG	72 KB	open | download	Rolly	11/20/2020	Read message
Boiler Generating Tube Calc3.jpg	470.7 KB	open | download	Rick.H	11/30/2020	Read message
Boundary Layer Concept.jpg	926.5 KB	open | download	Rick.H	11/30/2020	Read message
Boiler Generating Tube Calc5.jpg	503.8 KB	open | download	Rick.H	11/30/2020	Read message
Single IR Burner Design reduced.jpg	364.8 KB	open | download	Rick.H	11/30/2020	Read message
Chuk LSR Mono-Tube.jpg	508.9 KB	open | download	Rick.H	12/04/2020	Read message
Besler steam aircraft 1.png	183.3 KB	open | download	novice	12/09/2020	Read message
Besler steam aircraft 2.png	177 KB	open | download	novice	12/09/2020	Read message
Besler steam aircraft program conclusion.png	94 KB	open | download	novice	12/09/2020	Read message
Besler steam aircraft engine test 1.png	79.1 KB	open | download	novice	12/09/2020	Read message
Besler steam aircraft engine problems.png	71.4 KB	open | download	novice	12/09/2020	Read message
Besler steam aircraft engine steam condenser layout.png	94.7 KB	open | download	novice	12/09/2020	Read message
Boundary Layer ConvHF1.gif	5.2 KB	open | download	Rick.H	12/15/2020	Read message
Steam Turbine PT6 Concept.png	116.3 KB	open | download	Rick.H	12/15/2020	Read message
high efficiency steam engine energy balance.png	84.8 KB	open | download	novice	12/17/2020	Read message
high efficiency steam engine.png	68 KB	open | download	novice	12/17/2020	Read message
steam engine air condenser.png	572.1 KB	open | download	novice	12/17/2020	Read message
steam v6 engine-10.png	820.7 KB	open | download	novice	12/19/2020	Read message
steam v6 engine-21.png	985.9 KB	open | download	novice	12/19/2020	Read message
Boundary Layer Concept.jpg	926.5 KB	open | download	Rick.H	01/29/2021	Read message
Heat Transfer Coefficient vs Velocity.png	235.1 KB	open | download	Rick.H	02/17/2021	Read message
Boundary Layer ConvHF1.gif	5.2 KB	open | download	Rick.H	02/17/2021	Read message
G72103 0-4-0 Loco.jpg	270.1 KB	open | download	Rick.H	03/03/2021	Read message
Vulcan_Iron_Works_India_0-4-0.jpg	1007.9 KB	open | download	Rick.H	03/03/2021	Read message
Twin Clam Boiler.jfif	6.1 KB	open | download	Rick.H	03/04/2021	Read message
Twin Clam Boiler 2.jfif	10.8 KB	open | download	Rick.H	03/04/2021	Read message
Twin Clam Steam Motorcycle.png	7.4 KB	open | download	Rick.H	03/04/2021	Read message
1661900.pdf	331.1 KB	open | download	frustrated	03/23/2021	Read message
1688978.pdf	264.8 KB	open | download	frustrated	03/23/2021	Read message
1704441.pdf	389.1 KB	open | download	frustrated	03/23/2021	Read message
1982060.PDF	638.8 KB	open | download	frustrated	03/23/2021	Read message
Simple scheme.png	35.9 KB	open | download	frustrated	03/23/2021	Read message
735 Color Piping Diagram.jpg	500.2 KB	open | download	Rick.H	03/25/2021	Read message
aerospace-08-00059-g001.tif	448.8 KB	open | download	Rick.H	04/07/2021	Read message