Blackbird's thrust question
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Lyman,
That is because your position is weak.
No, I do not understand your position.
The "extraneous data" are facts that you, for whatever reason, choose to ignore in attempt to reenforce your position.
I know this is a waste of time but, I will give it one more try. Simplistically, for the SR-71 mission, the engines required a level of thrust capable of flying at 80,000 feet and Mach 3.3. To achieve this, an engine had to be designed to provide enough initial thrust to propel the aircraft to a high Mach (~2.2) when a ramjet function could take over to accelerate and maintain a speed of Mach 3.3. To achieve this goal, the turbojet (generator for the ramjet) had to function as well as the ramjet, itself. However, there was a problem at high Mach with the turbojet compressor. The air in the compressor could stagnate causing compressor blade flutter or even compressor stall where the turbojet engine would cease to function at all. So the solution was to take excess air somewhere from the turbojet engine and duct it back to the AB (ramjet burner). This could be accomplished a couple of ways, pull air out as it entered the engine or pull air out at a convenient location in the turbojet compressor. So as to make the engines fit into the hole in the designed nacelles and not make them bigger in diameter adding weight to the aircraft, the latter solution was chosen. In doing so, it does not modify the basic definition of a ramjet or the ramjet function, in fact it enhanced it by providing more air for combustion when mixed with fuel. It is still a ramjet working with a turbojet or a turbo-ramjet engine. All the by-pass tubes do are to ensure the turbojet still works at Mach 3.3.
TD
I cannot isolate any further the kernel of my position.
w/o extraneous data, would you simply say if you understand my position?
The "extraneous data" are facts that you, for whatever reason, choose to ignore in attempt to reenforce your position.
I know this is a waste of time but, I will give it one more try. Simplistically, for the SR-71 mission, the engines required a level of thrust capable of flying at 80,000 feet and Mach 3.3. To achieve this, an engine had to be designed to provide enough initial thrust to propel the aircraft to a high Mach (~2.2) when a ramjet function could take over to accelerate and maintain a speed of Mach 3.3. To achieve this goal, the turbojet (generator for the ramjet) had to function as well as the ramjet, itself. However, there was a problem at high Mach with the turbojet compressor. The air in the compressor could stagnate causing compressor blade flutter or even compressor stall where the turbojet engine would cease to function at all. So the solution was to take excess air somewhere from the turbojet engine and duct it back to the AB (ramjet burner). This could be accomplished a couple of ways, pull air out as it entered the engine or pull air out at a convenient location in the turbojet compressor. So as to make the engines fit into the hole in the designed nacelles and not make them bigger in diameter adding weight to the aircraft, the latter solution was chosen. In doing so, it does not modify the basic definition of a ramjet or the ramjet function, in fact it enhanced it by providing more air for combustion when mixed with fuel. It is still a ramjet working with a turbojet or a turbo-ramjet engine. All the by-pass tubes do are to ensure the turbojet still works at Mach 3.3.
TD
Last edited by Turbine D; 30th Jan 2013 at 17:53. Reason: Correct grammar and punctuation
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Some very embarrassing statements from somebody here.
First, best not to believe what you read on the internet.
All I can do is hopefully lead you to water.
Bob Abernethy's Untold tales is very good. It is too short unfortunately to explain much but we are in luck because we have the essential complement to his 'tales' in the form of the 'bible' he wrote on how he fixed the J58 to work at Mach 3.2. It is called US Patent 3,344,606.
Read the patent and then tell us what you have learned.
Read the patent and then tell us what you have learned.
Bear in mind 'Bob' designed and built real engines that made money. He didn't write textbooks.Read the patent and then tell us what you have learned.
Embarrassing statement
Embarrassing statement. Read the patent. Tell us what you have learned.
There is much information on the internet about this subject, if you would only search and find it.
All I can do is hopefully lead you to water.
Bob Abernethy's Untold tales is very good. It is too short unfortunately to explain much but we are in luck because we have the essential complement to his 'tales' in the form of the 'bible' he wrote on how he fixed the J58 to work at Mach 3.2. It is called US Patent 3,344,606.
From Aerostories
Mach numbers the new engine would be unable to cope with the volume of air coming through the air-intakes
Mach numbers the new engine would be unable to cope with the volume of air coming through the air-intakes
installing a series of fixed flow-vanes downstream
From Aircraft Engine Design:
Turbojet/Ramjet Combined Cycle Engine.When these tubes are in use, the compressor, burner, and turbine of the turbojet are essentially bypassed
Turbojet/Ramjet Combined Cycle Engine.When these tubes are in use, the compressor, burner, and turbine of the turbojet are essentially bypassed
If you are still having trouble understanding,
The air in the compressor could stagnate causing compressor blade flutter or even compressor stall where the turbojet engine would cease to function at all
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peter....
In the description portion of the patent, the author describes "Increasing Ram air temperature" as the drawback to high speed turbojet operation, then further, that the purpose of the bleed air is to cool the compressor then reinject the bleed into the ejector to be "reheated"...
My sense thus far is that rather than ennabling a Ram function, his purpose is to defeat it.....
The document resists copying, so I guess I could say:
Read the patent......
Continuing, the inventor actually suggests possible options to the turbojet problem. His "Option 3" he actually labels the "Turbo-Ramjet", which he rejects as too heavy. This option involves bypassing completely the Turbo machinery.
In the description portion of the patent, the author describes "Increasing Ram air temperature" as the drawback to high speed turbojet operation, then further, that the purpose of the bleed air is to cool the compressor then reinject the bleed into the ejector to be "reheated"...
My sense thus far is that rather than ennabling a Ram function, his purpose is to defeat it.....
The document resists copying, so I guess I could say:
Read the patent......
Continuing, the inventor actually suggests possible options to the turbojet problem. His "Option 3" he actually labels the "Turbo-Ramjet", which he rejects as too heavy. This option involves bypassing completely the Turbo machinery.
Last edited by Lyman; 30th Jan 2013 at 19:30.
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If the airflow feeding what you term the Ramjet "section" of the J58 is isolated from the internal machinery of the turbojet in toto, there would (technically) be a Ramjet "component" to the engine's power. If the source of this air is the compressor section, you are completely, and patently, wrong. I do not care who endorses the definition, Ramjets operate from passive air, not mechanically enhanced air.
Too many classifications add no value . They require explanations. Just say what it is.
Engine A is a dual cycle. What does that mean? Well, above a certain speed it bleeds off some air.
Engine B is a dual cycle. Oh you mean... No! It's got variable stators...
Engine C is like a ramjet at high speeds. Right, that's because.... No It's got a spike like ramjet intakes. Oh, thanks.
J58? Just tell it like it is.
However there is an audience that wants classifications and intuitive 'understanding'.
KJ knew this (Discovery video for public consumption). Why didn't he call it a flow inducer on the program? Wrong audience. He saved that for "Our good friends at Pratt and Whitney do not like us to say that at high speeds their engine is only a flow inducer and that, after all, it is the nacelle pushing the airplane".
Continuing, the inventor actually suggests possible options to the turbojet problem. His "Option 3" he actually labels the "Turbo-Ramjet", which he rejects as too heavy. This option involves bypassing completely the Turbo machinery.
the purpose of the bleed air is to cool the compressor then reinject the bleed into the ejector to be "reheated"...
Salute!
This is getting ridiculous about "names".
I have to agree with those here that do not think/believe the J-58 was in any way a "ram jet" once above 2.x M.
The clever engineers at Pratt figured out how to use all the air being crammed into the motor to use it in the burner. At the same time, they reduced some temperature and other bad things on the "core" engine. They also realized that you couldn't get a lotta thrust with a pure turbojet at the speeds they were trying to reach.
Had the J-58 been a combined cycle turbo-ramjet, it would have resembled the F100 that Pratt developed for the Eagle and Viper. An annular bypass, but a mechanism to close off most, if not all, air entering the core. The hot, compressed air from the intake would go directly to the "burner" section and act just as a traditional ram jet.
The J-58 did some of this, but the air being bypassed was nowhere near enough or hot enough to provide what is needed for a ram jet.
It should be noted that many of the early ( 1950 - 196x) turbojets had burners that could still add fuel to the unburned air that came thru the core. So the Pratt folks developed a way to bypass a lotta useless air and feed it directly to the burner and gain a lotta efficiency and thrust - up to a point.
A complete changover to a ram jet above 2.x M would have allowed the Blackbird a much higher speed/altitude, but the materials for the structure could not handle the heat. And the Blackbird did not have "thrusters" to control pitch, yaw and roll once really high - it was all aero forces on the control surfaces, shock waves and all.
The J-58 was a super motor, and it served us well for many years. But it was not a "turbo-ramjet".
That's my story, and I am stickin' to it.
This is getting ridiculous about "names".
I have to agree with those here that do not think/believe the J-58 was in any way a "ram jet" once above 2.x M.
The clever engineers at Pratt figured out how to use all the air being crammed into the motor to use it in the burner. At the same time, they reduced some temperature and other bad things on the "core" engine. They also realized that you couldn't get a lotta thrust with a pure turbojet at the speeds they were trying to reach.
Had the J-58 been a combined cycle turbo-ramjet, it would have resembled the F100 that Pratt developed for the Eagle and Viper. An annular bypass, but a mechanism to close off most, if not all, air entering the core. The hot, compressed air from the intake would go directly to the "burner" section and act just as a traditional ram jet.
The J-58 did some of this, but the air being bypassed was nowhere near enough or hot enough to provide what is needed for a ram jet.
It should be noted that many of the early ( 1950 - 196x) turbojets had burners that could still add fuel to the unburned air that came thru the core. So the Pratt folks developed a way to bypass a lotta useless air and feed it directly to the burner and gain a lotta efficiency and thrust - up to a point.
A complete changover to a ram jet above 2.x M would have allowed the Blackbird a much higher speed/altitude, but the materials for the structure could not handle the heat. And the Blackbird did not have "thrusters" to control pitch, yaw and roll once really high - it was all aero forces on the control surfaces, shock waves and all.
The J-58 was a super motor, and it served us well for many years. But it was not a "turbo-ramjet".
That's my story, and I am stickin' to it.
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Peter,
I assume the embarrassing statement from somebody here, you point out, are contributed to me, so I will respond accordingly. First about Dr. Bob Abernethy:
From his web site, Bob Abernethy.com:
Dr. Abernethy did indeed write a number of books and publications which are listed on his web site.
Bob didn't design and build real engines, he happened to come up with a solution to a problem that a real engine was having and it fixed that problem, making it a money maker instead of a money loser. Actually teams of people design jet engines, not one individual.
It is where I got the Abernethy/P&W patent some time ago but thought it might be too technical for some to fully understand. Also, Abernerthy's web site would be a source of information I would believe.
I've read the patent. You do know that patents are written to generally disclose the invention, but, not to give too much information away. A couple of things I will point out to you:
From the patent:
Actually, this would have solved the problem in the compressor which had two different problems, Stall and Choked, however, it happened there was patent for this feature: Us Patent 2,931,168 titled Variable Stator Engine Control System, Application Date - 5/24/1955, Patented 4/5/1960, Assigned to General Electric Company. You can easily hold the actuator arm in one hand and the piston controlling the arm in the other, not that heavy, and leakage is not a problem, Would have required modifications to the compressor casing and vanes, plus some time, but the patent was a problem.
From the patent claims:
I could go on, but I think you can see the information I provided is not embarrassing even if you may think so. I think Gums is right, forget the names, the engine worked and Dr. Abernethy had a great idea....
TD
I assume the embarrassing statement from somebody here, you point out, are contributed to me, so I will respond accordingly. First about Dr. Bob Abernethy:
From his web site, Bob Abernethy.com:
Dr. Robert B. Abernethy is known worldwide for his expertise in jet engine performance, measurement uncertainty analysis and Weibull analysis. He joined Pratt & Whitney Aircraft in 1955. He retired from Pratt & Whitney Aircraft in 1987 after 32 years as Manager of Reliability, Safety, Maintainability, and Statistical analysis to teach Weibull analysis. He holds the patent on a feature of the J58 Pratt & Whitney engine that powers the world’s fastest aircraft. His invention converts the afterburning turbojet into a partial ram jet at high Mach number.
Bear in mind 'Bob' designed and built real engines that made money. He didn't write textbooks.Read the patent and then tell us what you have learned.
First, best not to believe what you read on the internet.
Read the patent and then tell us what you have learned.
From the patent:
A second solution to the flow blockage problem has been suggested in the form of mechanical rotation of the stator vanes in the front and rear compressor stages to improve the air angles. This proposed solution has several severe disadvantages in that the stator control must be precise and the angular rotation would have to be different for each compressor stage. Consequently, an intricate control mechanism would be required and malfunction of the control would be disastrous. In view of the complexity of the control mechanism, leakage through the actuating mechanism would be almost impossible to eliminate. Further, engine weight would be substantially increased thereby and it would be almost impossible to rotate the stator vanes to an angle which would be optimum for both stator vane angle and its associated blade air angle, whereas, my recover bleed air engine rematches both vanes and blades.
Pratt & Whitney therefore modified their JT-11 by installing a series of fixed flow-vanes downstream of the 4th compressor stage
A plurality of guide or turning vanes are positioned within fish-tail inlet to smoothly guide the bleed air into ducts which are of substantially circular cross section.
TD
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Hi gums...
you say...."The clever engineers at Pratt figured out how to use all the air being crammed into the motor to use it in the burner. At the same time, they reduced some temperature and other bad things on the "core" engine. They also realized that you couldn't get a lotta thrust with a pure turbojet at the speeds they were trying to reach."
I was about to sit down and take four paragraphs to say just that. Clear, concise, in english....
In the patent, a guy lays out the problem, offers options, and proposes a solution, making claims, and offers drawings and supporting material. I have been through it, and have a patent pending for a novel helicopter controls system.
For the record, the words "Partial Ramjet" are oxymoronic. A Ramjet is not a ramjet until a very specific point is reached, at which it becomes an engine, full on, no partial about it. It is either running, or it is not. It does not fill the role of "conttributory", as if it was some form of "Turbocharger".
Believe it or not, the Patent Office does not require a working prototype, or that the solution even work....
The inventor in question, here, Abernethy, calls his invention a bleed air recapture system.
He proposes the problem that all turbojets have, loss of power, efficiency, and off the chart temps, as it approaches very high Mach.
He says there are two causes, excess Temperature, and excess airflow, which "chokes" the compressor.
Both of these problems are....ready? Created by RAM AIR. So the problem is Ram AIR, too hot, too thick, and what do we do? Here he proposes to drain some bleed air from the fourth stage of the Compressor, which instantly unblocks the compressor (choke) and moves aft through the six ducts, to enter the Ejector, for added mass, and expansion.
This process also cools the compressor and Turbine, and the Ejector LINER, the case.
I am going back in to find the text where he identifies cooling function, and reheat.
back in a bit.......
from the PATENT (claims)...
"...my new engine provides cool bleed air to the afterburner for cooling purposes."
That does not sound like he is "turning the afterburner into a "partial RamJet".
As the "website" purportedly claims.
He specifically eliminates the nomenclature "RAMJET" as one of his"proposed" and ELIMINATED options. Number (3). "TURBO RAMJET", the name itself, is rejected by this man as descriptive of "his engine"...in hisown words (through his patent attorney).
But do read the patent, it is informative, seems to have cleared up some murk, and is pretty typical of Patent text in general.
cheers, Lyman
you say...."The clever engineers at Pratt figured out how to use all the air being crammed into the motor to use it in the burner. At the same time, they reduced some temperature and other bad things on the "core" engine. They also realized that you couldn't get a lotta thrust with a pure turbojet at the speeds they were trying to reach."
I was about to sit down and take four paragraphs to say just that. Clear, concise, in english....
In the patent, a guy lays out the problem, offers options, and proposes a solution, making claims, and offers drawings and supporting material. I have been through it, and have a patent pending for a novel helicopter controls system.
For the record, the words "Partial Ramjet" are oxymoronic. A Ramjet is not a ramjet until a very specific point is reached, at which it becomes an engine, full on, no partial about it. It is either running, or it is not. It does not fill the role of "conttributory", as if it was some form of "Turbocharger".
Believe it or not, the Patent Office does not require a working prototype, or that the solution even work....
The inventor in question, here, Abernethy, calls his invention a bleed air recapture system.
He proposes the problem that all turbojets have, loss of power, efficiency, and off the chart temps, as it approaches very high Mach.
He says there are two causes, excess Temperature, and excess airflow, which "chokes" the compressor.
Both of these problems are....ready? Created by RAM AIR. So the problem is Ram AIR, too hot, too thick, and what do we do? Here he proposes to drain some bleed air from the fourth stage of the Compressor, which instantly unblocks the compressor (choke) and moves aft through the six ducts, to enter the Ejector, for added mass, and expansion.
This process also cools the compressor and Turbine, and the Ejector LINER, the case.
I am going back in to find the text where he identifies cooling function, and reheat.
back in a bit.......
from the PATENT (claims)...
"...my new engine provides cool bleed air to the afterburner for cooling purposes."
That does not sound like he is "turning the afterburner into a "partial RamJet".
As the "website" purportedly claims.
He specifically eliminates the nomenclature "RAMJET" as one of his"proposed" and ELIMINATED options. Number (3). "TURBO RAMJET", the name itself, is rejected by this man as descriptive of "his engine"...in hisown words (through his patent attorney).
But do read the patent, it is informative, seems to have cleared up some murk, and is pretty typical of Patent text in general.
cheers, Lyman
Last edited by Lyman; 30th Jan 2013 at 23:35.
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Turbine D,
I apologise for any misunderstandings. I felt that explanations like "the engine would be unable to cope with the volume of air" and "the air in the compressor could stagnate.." would not help people trying to grasp what was happening, whilst the patent explains the whole high inlet temp/low corrected speed problem correctly in a nutshell.
As you were suggesting these sources of information I got the wrong end of the stick.
Although you say the patent should not give much away, it seems an amazing first primer in compressor operation in general terms and more specifically at high inlet temps. Just seemed too good to not be made more visible.
I'm fully aware of Bob Abernethy's role as the 'father' of the M3 J58 ref my copy of Jack Connors book.and unfortunaley, again, was not on your wavelength. I have
Thank you for the variable stator story.
I apologise for any misunderstandings. I felt that explanations like "the engine would be unable to cope with the volume of air" and "the air in the compressor could stagnate.." would not help people trying to grasp what was happening, whilst the patent explains the whole high inlet temp/low corrected speed problem correctly in a nutshell.
As you were suggesting these sources of information I got the wrong end of the stick.
Although you say the patent should not give much away, it seems an amazing first primer in compressor operation in general terms and more specifically at high inlet temps. Just seemed too good to not be made more visible.
I'm fully aware of Bob Abernethy's role as the 'father' of the M3 J58 ref my copy of Jack Connors book.and unfortunaley, again, was not on your wavelength. I have
Thank you for the variable stator story.
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But it was not a "turbo-ramjet"
In the adoption of the position that the engine featured no "ramjet" function, you need to explain,
Why Kelly Johnson, the aircrafts designer, refers to "ramjet"
Why the aircrafts pilots refer to "ramjet"
Why the aircrafts instructors refer to "ramjet"
Why the P & W engineer assigned to oversee the in service use of the engine refers to "ramjet"
Why the people assigned to command the operation of the aircraft refer to "ramjet"
Were all these people so stupid that they didn't know what they were talking about?
Last edited by Brian Abraham; 31st Jan 2013 at 01:33.
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Abernethy is very specific about "Turbo-Ramjet". He introduces it as a potential approach to solve the problem of high inlet temperature and blocking, (choking) of the compressor. He describes it as heavy, utilizing 100 percent air flow from around, (bypassing) the core and unworkable.
As to "Partial Ramjet" I write above re: Abernethy utilizing the bleeds to "cool" the afterburner. By cool, he means a titch shy of melting. That does not describe a ramjet, and as I wrote above, a RamJet is an all or nothing concept, there is no "kind of" pregnant.
As to why the term "ramjet" became au courant in the fraternity, I can only guess. In the fifties and sixties, a Ramjet was a concept that was tantalizing, though the idea had been around since the early nineteen hundreds.
Abernethy does refer to "Ram Air" in passing, and defines it as the source of the problem for high speed supersonic turbojet propulsion... He describes it as too hot, and too dense, to manage through the compressor inlet,, it choked the compressor section, (not a stall, essentially the opposite), and prevented the turbojet from getting into seriously high speed regimes.
His resolution of the obstacles caused by 'Ram Air', got the attention of everyone, and though misunderstood, came into the jargon as "Ramjet", when in fact Abernethy specifically denied the concept in his patent....
So the J58 is not a Ramjet, not a Turbo Ramjet, and not a Partial Ramjet...
It is a "Recovered bleed air system"....
I think the misunderstanding perpetuated throughout the community as 'jargon' since it really wasn't utterly wrong, and had a cachet that fit the times, it leant myth and mastery to the fraternity, a fraternity that was in serious competition with Mercury, and Canaveral, for big dough, and bragging rights....
I don't particularly enjoy the pedantic role, but I love a spirited discussion....
great respect, Brian Abraham...
As to "Partial Ramjet" I write above re: Abernethy utilizing the bleeds to "cool" the afterburner. By cool, he means a titch shy of melting. That does not describe a ramjet, and as I wrote above, a RamJet is an all or nothing concept, there is no "kind of" pregnant.
As to why the term "ramjet" became au courant in the fraternity, I can only guess. In the fifties and sixties, a Ramjet was a concept that was tantalizing, though the idea had been around since the early nineteen hundreds.
Abernethy does refer to "Ram Air" in passing, and defines it as the source of the problem for high speed supersonic turbojet propulsion... He describes it as too hot, and too dense, to manage through the compressor inlet,, it choked the compressor section, (not a stall, essentially the opposite), and prevented the turbojet from getting into seriously high speed regimes.
His resolution of the obstacles caused by 'Ram Air', got the attention of everyone, and though misunderstood, came into the jargon as "Ramjet", when in fact Abernethy specifically denied the concept in his patent....
So the J58 is not a Ramjet, not a Turbo Ramjet, and not a Partial Ramjet...
It is a "Recovered bleed air system"....
I think the misunderstanding perpetuated throughout the community as 'jargon' since it really wasn't utterly wrong, and had a cachet that fit the times, it leant myth and mastery to the fraternity, a fraternity that was in serious competition with Mercury, and Canaveral, for big dough, and bragging rights....
I don't particularly enjoy the pedantic role, but I love a spirited discussion....
great respect, Brian Abraham...
Last edited by Lyman; 31st Jan 2013 at 02:13.
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Well, we have a real problem on our hands, seems Bob Abernethy doesn't know what he's talking about.
Actually it converted the engine into a partial ramjet with capability above Mach 3! I called it the Recover Bleed Air engine on my patent. Here you see my drawing of the duct in my patent disclosure
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I went out on a limb as to "partial ramjet", if that is accurate there is a "partial problem".
First, he did nullify the 58 as a Turbo Ramjet. That much is in the patent, unless he said something to contradict, elsewhere. It most certainly is not a pure Ramjet, that is obvious....as to "partial", I may be the only one, but I stand by my statement, there is no such thing.
If this "partial Ramjet" is working, from whence comes the Ram? If you answer "Bleed" then you put yourself in a corner, by definition, linguistically if not technically also.
The origin of inlet Air for a Ramjet is from the airstream. If it is mechanically enhanced, it does not meet the standard definition and is not a ramjet, partial or otherwise.
Abernethy describes this engine's inlet (J58) as being frustrated by "Ram Air".
The Ram creates high temps, and blocks the Compressor section.
So Abernethy reduces the temperature and block by decreasing the pressure at the compressor initial stage. At this point, having decreased the Ram, the bleed travels back to the combustor. The bleed has lower pressure and cooler temperature than the core gaspath and enters the afterburner, and becomes by definition only a Ram Jet? By decreasing pressure and cooling? That is the opposite of the standard mechanism for a Ramjet. Reducing pressure and temperature in the chamber describes ramjet?
Arse About....
First, he did nullify the 58 as a Turbo Ramjet. That much is in the patent, unless he said something to contradict, elsewhere. It most certainly is not a pure Ramjet, that is obvious....as to "partial", I may be the only one, but I stand by my statement, there is no such thing.
If this "partial Ramjet" is working, from whence comes the Ram? If you answer "Bleed" then you put yourself in a corner, by definition, linguistically if not technically also.
The origin of inlet Air for a Ramjet is from the airstream. If it is mechanically enhanced, it does not meet the standard definition and is not a ramjet, partial or otherwise.
Abernethy describes this engine's inlet (J58) as being frustrated by "Ram Air".
The Ram creates high temps, and blocks the Compressor section.
So Abernethy reduces the temperature and block by decreasing the pressure at the compressor initial stage. At this point, having decreased the Ram, the bleed travels back to the combustor. The bleed has lower pressure and cooler temperature than the core gaspath and enters the afterburner, and becomes by definition only a Ram Jet? By decreasing pressure and cooling? That is the opposite of the standard mechanism for a Ramjet. Reducing pressure and temperature in the chamber describes ramjet?
Arse About....
Last edited by Lyman; 31st Jan 2013 at 03:27.
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I hate repeating myself. Bob Abernethy himself wrote.
You saying he doesn't understand what it was he patented? I'll repeat his partial quote in big letters
it converted the engine into a partial ramjet
Actually it converted the engine into a partial ramjet with capability above Mach 3! I called it the Recover Bleed Air engine on my patent. Here you see my drawing of the duct in my patent disclosure
it converted the engine into a partial ramjet
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I got it the first time. Put that aside and explain why my opinion is wrong....
His description is extensive in the patent, he adds mass to the ab and it is combusted, increasing thrust. The term partial ramjet does not appear...
How is that different from a standard turbojet. Can you explain?
And no, I am not saying he does not understand, only that I do not....
Abernethy's design introduces compressed air into a combustion chamber.
"A Ramjet has no mechanical compressor..." NASA Glenn Research Center
His description is extensive in the patent, he adds mass to the ab and it is combusted, increasing thrust. The term partial ramjet does not appear...
How is that different from a standard turbojet. Can you explain?
And no, I am not saying he does not understand, only that I do not....
Abernethy's design introduces compressed air into a combustion chamber.
"A Ramjet has no mechanical compressor..." NASA Glenn Research Center
Last edited by Lyman; 31st Jan 2013 at 04:09.
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Lyman, I don't know why you continue to be so obtuse, and fail to understand what Bob Abernethy is saying. I'll spell it out for one very, very last time.
Bob Abernethy said it's a partial ramjet, but I called it a Recover Bleed Air engine on my patent
Confine yourself to that one statement. What part of it do you not understand?
Bob Abernethy said it's a partial ramjet, but I called it a Recover Bleed Air engine on my patent
Confine yourself to that one statement. What part of it do you not understand?
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Hi Brian
The disconnect is most clear. I have a point of view. The reality as I see it is the function, not the name.
The title does not matter to me so much as it matters to you.
To be Precise. The owner of the patent knows his work. He has assigned two titles to it. One title is informal, the other official.
I will continue to refer to it by its officially recognized title. I am less insistent in its title than in its function, which you seem to be disconnected from, as you refuse to discuss the machine on its merits.
I am not being unreasonable. I wish to discuss the function, the purpose, and the theory. The name has caused some interest in the discussion. At every turn, you jump in, get excited, and focus on the progenitor of the interest, instead of recognizing the worth of the give and take.
If I have been guilty of that, I apologize. I acknowledge the statement you make.
A Ramjet system has no mechanical compressor. A true statement. The argument should be about why Abernethy calls his invention a partial ramjet.
The tension should be between the official rule for Ramjets and the inventors apparent dismissal of it.
There be the treasure...
Be well...
The disconnect is most clear. I have a point of view. The reality as I see it is the function, not the name.
The title does not matter to me so much as it matters to you.
To be Precise. The owner of the patent knows his work. He has assigned two titles to it. One title is informal, the other official.
I will continue to refer to it by its officially recognized title. I am less insistent in its title than in its function, which you seem to be disconnected from, as you refuse to discuss the machine on its merits.
I am not being unreasonable. I wish to discuss the function, the purpose, and the theory. The name has caused some interest in the discussion. At every turn, you jump in, get excited, and focus on the progenitor of the interest, instead of recognizing the worth of the give and take.
If I have been guilty of that, I apologize. I acknowledge the statement you make.
A Ramjet system has no mechanical compressor. A true statement. The argument should be about why Abernethy calls his invention a partial ramjet.
The tension should be between the official rule for Ramjets and the inventors apparent dismissal of it.
There be the treasure...
Be well...
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Lyman,
To be precise, Abernethy did not "assign two titles" to his engine. He assigned a title to his patent, but said the engine was "actually", that is, in reality, a partial ramjet. I'll go along with that
Dick
To be precise, Abernethy did not "assign two titles" to his engine. He assigned a title to his patent, but said the engine was "actually", that is, in reality, a partial ramjet. I'll go along with that
Dick
Last edited by Dick Whittingham; 31st Jan 2013 at 13:53.