The OTHER X-15-A-2 Hypersonic Ramjet - Tony Ferri's Thermal Compression Engine

[DSE]

HYPERSONIC RAMJET RESEARCH ENGINE PROJECT VOLUME I : MA-165 DESIGN DESCRIPTION
Title: Preliminary Design Report - Hypersonic Ramjet Research Engine Project
Online Source: Click to View PDF File [PDF Size: 9.0 MB]
Add'l Title Information: Volume 1; MA-165 Design Description
Author: Bendot, J. G.
Abstract: No abstract available
Collection: NASA
NASA Center: NASA (Unspecified Center)
Publication Date: Feb 28, 1966
Publication Year: 1966
Document ID: 19750070923
Accession Number: 75N77171
Subject Category: GENERAL
Report/Patent Number: NASA-CR-66230, REPT-6102-VOL-1
Contract/Grant/Task Number: NAS1-5117
Publication Information: Number of pages = 101
Language: English
Subject Terms: DYNAMIC STRUCTURAL ANALYSIS; ENGINE CONTROL; ENGINE DESIGN; ENGINE TESTS; FLIGHT TESTS; PERFORMANCE PREDICTION; SAFETY MANAGEMENT; SUPERSONIC COMBUSTION RAMJET ENGINES
Accessibility: Unclassified; Publicly available; Unlimited; No Copyright
Document Source: CASI
Updated/Added to NTRS: May 12, 2010

http://ntrs.nasa.gov/search.jsp?R=19750070923&hterms=ma-165&qs=Ntx%3Dmode%2520matchallany%26Ntk%3DAll%26Ns%3DLoaded-Date|1%26N%3D0%26Ntt%3Dma-165

Preliminary design report hypersonic ramjet research engine project. Volume 2: Appendixes
Title: Preliminary design report hypersonic ramjet research engine project. Volume 2: Appendixes
Online Source: Click to View PDF File [PDF Size: 12.3 MB]
Collection: NASA
NASA Center: NASA (Unspecified Center)
Publication Date: Feb 28, 1966
Publication Year: 1966
Document ID: 19760065228
Accession Number: 76N70269
Subject Category: GENERAL
Report/Patent Number: NASA-CR-66231, REPT-6102-VOL-2
Contract/Grant/Task Number: NAS1-5117
Publication Information: Number of pages = 300
Language: English
Subject Terms: COOLING SYSTEMS; ENGINE CONTROL; ENGINE DESIGN; FUEL SYSTEMS; HYPERSONIC FLIGHT; INSTRUMENTS; RAMJET ENGINES; RELIABILITY ANALYSIS; STRUCTURAL ANALYSIS
Accessibility: Unclassified; Publicly available; Unlimited; No Copyright
Document Source: CASI
Updated/Added to NTRS: Jul 21, 2008

http://ntrs.nasa.gov/search.jsp?R=19760065228&hterms=ma-165&qs=Ntx%3Dmode%2520matchallany%26Ntk%3DAll%26Ns%3DLoaded-Date|1%26N%3D0%26Ntt%3Dma-165

 

[shockonlip]

Thanks DSE.
I have seen Volume 1 before, but not Volume 2. So now I can add Volume 2
to the stack to go through. Looking forward to it.

I wish they had given the go-ahead on this engine instead of the Garrett
engine. Podded engines are not the way to go, and it was probably too hard
back in the 1960's. Given the 3-D CFD required for this they may not have
succeeded, because they didn't have 3D CFD and microprocessors for control.
But by funding this, you would have had the best ramjet engine house in the US,
and Tony Ferri (and probably GASL) working on it together. Maybe Fred Billig
and JH-APL would have jumped in too. The scramjet dream team !! That would have
been worth it in my opinion. What would such a team have come up with !!

To the uninitiated, thermal compression is utilizing combustion wave compression
effects along with the compression of a fixed geometry inlet. You position fuel
injectors at strategic locations in the engine and modulate which ones turn on
and off and control the fuel rate to achieve the desired combustion and compression
over and above what the inlet has already produced. One of Ferri's clever ideas.

 

[DSE]

I wish they had given the go-ahead on this engine instead of the Garrett
engine. Podded engines are not the way to go, and it was probably too hard
back in the 1960's. Given the 3-D CFD required for this they may not have
succeeded, because they didn't have 3D CFD and microprocessors for control.
But by funding this, you would have had the best ramjet engine house in the US,
and Tony Ferri (and probably GASL) working on it together. Maybe Fred Billig
and JH-APL would have jumped in too. The scramjet dream team !! That would have
been worth it in my opinion. What would such a team have come up with !!

Not so sure about that. Antonio Ferri was also a NASA Langley person and while there was some cooperative work between the Langley scramjet group and JHU-APL, there wasn't much love lost between the two even into the 80s, and 90s. You will almost never see any reference to any Langley scramjet work in papers from JHU-APL in that era.

 

[shockonlip]

You may be correct, but I encountered a testimonial of Tony Ferri
by Fred Billig which I took my comments from:

"Facing the Heat Barrier: A History of Hypersonics"
by: T. A. Heppenheimer

pg. 107
"Fred Billig was one who accepted the merits of thermal compression and
gave his own analyses. He proposed that at Mach 5, thermal compression could
increase an engine’s specific impulse, an important measure of its performance, by
61 percent. Years later he recalled Ferri’s “great capability for visualizing, a strong
physical feel. He presented a full plate of ideas, not all of which have been realized.”39

39 Journal of Spacecraft and Rockets, September 1968, pp. 1076-81. Quote: Fred Billig interview,
16 October 1987. Folder 18649, NASA Historical Reference Collection, NASA History Division,
Washington, D.C. 20546.

 

[shockonlip]

So DSE,

Is JH-APL scramjet group just fading away?

I am not aware of new players.

Fred is gone, Waltrup is gone. Van Wie I hear is into
something else (not sure of that, Paul Czysz said something
like that in one of those online hypersonics classes).
Dave had been doing that plasma stuff.

So is anyone carrying the torch forward for them?

 

[DSE]

You may be correct, but I encountered a testimonial of Tony Ferri
by Fred Billig which I took my comments from:

"Facing the Heat Barrier: A History of Hypersonics"
by: T. A. Heppenheimer

pg. 107
"Fred Billig was one who accepted the merits of thermal compression and
gave his own analyses. He proposed that at Mach 5, thermal compression could
increase an engine’s specific impulse, an important measure of its performance, by
61 percent. Years later he recalled Ferri’s “great capability for visualizing, a strong
physical feel. He presented a full plate of ideas, not all of which have been realized.”39

39 Journal of Spacecraft and Rockets, September 1968, pp. 1076-81. Quote: Fred Billig interview,
16 October 1987. Folder 18649, NASA Historical Reference Collection, NASA History Division,
Washington, D.C. 20546.

Well the devil is always in the details isn't it? If imitation is the sincerest form of flattery and it was such a good idea, why didn't Billig or someone else make use of it? If one reads the '68 JSR reference you will see Billig's analysis/evaluation of the thermal compression process is of the most very idealized theoretical sense. Nothing wrong with that, as long as one recognizes this, similar to say the Carnot efficiency for any heat engine.The idealized analysis uses a two stream stream approach where the thermally compressed stream only interacts with the main fluid stream through the engine via the "boundary" between them. There is no mixing between the streams. So in essence the thermally compressed stream can be thought of as a simple variation of variable geometry. Now that said, start taking a look at all the practical the real world engineering features and processes required in trying to implement this idea in a real device. Injection, mixing land Rayleigh losses in the total stream, followed by reduced O2 content in the total stream. But it's hard enough to get the fuel to mix and burn in an efficient manner in the combustor, now you need to do this in the faster moving inlet flow where the temperature and pressure are even lower than in a normal combustor. Rayleigh losses also scale with Mach number. This is seen in the JSR paper where the 61% Isp increase at Mach 5 is reduced to only 3.5% at Mach 12. Moving into the combustor, you have all ready burned a fraction of the O2 in the inlet and haven't made any thrust yet. However, you have made your job of injecting and mixing and burning fuel in the combustor harder because it is harder to find and mix with the remaining O2. Same problem as one is challenged with in staged injection schemes required at low Mach to deal with limitations in area ratio schedule in the combustor. It works at Mach 5 because it is relatively easy to make thrust here. Cruise typically requires phi~0.7 or so. Not the case as you go up in Mach and the ratio of the amount of energy added to the flow due to combustion becomes a smaller fraction of the total energy of the flow. The formula of M2/89 is typically used here to express this ratio.

On top of all of this now consider the system level costs, remember a hypersonic vehicle is an MDAO problem. It needs a whole other fuel injection and control system. Start to see the real picture? Has it bought its way into the system?

 

[DSE]

So DSE,

Is JH-APL scramjet group just fading away?

I am not aware of new players.

Fred is gone, Waltrup is gone. Van Wie I hear is into
something else (not sure of that, Paul Czysz said something
like that in one of those online hypersonics classes).
Dave had been doing that plasma stuff.

So is anyone carrying the torch forward for them?

There still are some of what were the "young folks" from the NASP days around and a few new faces have been added. Unfortunately, the facilities they had in the past are long gone. When NASA defunded hypersonics after Hyper-X, that fact was used at JHU-APL as reasoning to get rid of the facilities and use the space for other uses. I think Aerojet got at least some of the hardware.

As an aside I was lucky enough to work a little bit with Paul Waltrup as a technical reviewer on a program before he passed away. I have have also interacted a small bit with Dick Orth in his work with John Anderson in trying to set up a hypersonics exhibit at NASM.

 

[DSE]

Well the devil is always in the details isn't it? If imitation is the sincerest form of flattery and it was such a good idea, why didn't Billig or someone else make use of it? If one reads the '68 JSR reference you will see Billig's analysis/evaluation of the thermal compression process is of the most very idealized theoretical sense. Nothing wrong with that, as long as one recognizes this, similar to say the Carnot efficiency for any heat engine.

FWIW, Billig did a second JSR article in 1972, V9,N9, pp702-703, Two-Dimensional Model for Thermal Compression. A telling tale is the final sentence, "The very formidable problem of developing a fuel distribution system for a realistic engine design that would place planar flame fronts in the desired locations is beyond the scope of this discussion."

 

[DSE]

FWIW, I recently found this tidbit about A. Ferri and GASL on NTRS.

http://ntrs.nasa.gov/search.jsp?R=19920012276&hterms=erdos+gasl+ferri+gasl+ferri&qs=Ntx%3Dmode%2520matchallany|mode%2520matchall%26Ntk%3DAll|Author-Name%26Ns%3DLoaded-Date|1%26N%3D0%26Ntt%3Dgasl%2520ferri|erdos

Pioneering scramjet developments by Antonio Ferri
Online Source: Click to View PDF File [PDF Size: 405 KB]
Author: Erdos, John I.; Nucci, Louis M.
Abstract:
The concept is summarized of a diffusive burning supersonic combustion hide hide
ramjet engine (scramjet) envisioned by Antonio Ferri and some of the salient technologies are highlighted as developed by General Applied Science Labs, PIBAL, and NYU, under his direction.
Collection: NASA
NASA Center: NASA (Unspecified Center)
Publication Date: JAN 1, 1992
Publication Year: 1992
Document ID: 19920012276
Accession Number: 92N21519
Subject Category: AIRCRAFT PROPULSION AND POWER
Publication Information: NASA. Lewis Research Center, Rocket-Based Combined-Cycle (RBCC) Propulsion Technology Workshop. Tutorial Session; 10 p; Number of pages = 10
Language: English
Subject Terms: BURNERS; DIFFUSIVITY; PROPULSION SYSTEM CONFIGURATIONS; PROPULSION SYSTEM PERFORMANCE; SUPERSONIC COMBUSTION RAMJET ENGINES
Notes: In NASA. Lewis Research Center, Rocket-Based Combined-Cycle (RBCC) Propulsion Technology Workshop. Tutorial Session 10 p (SEE N92-21517 12-20)
Accessibility: Unclassified; Publicly available; Unlimited; No Copyright
Document Source: CASI
Updated/Added to NTRS: May 12, 2008

 

[shockonlip]

You may be correct, but I encountered a testimonial of Tony Ferri
by Fred Billig which I took my comments from:

"Facing the Heat Barrier: A History of Hypersonics"
by: T. A. Heppenheimer

pg. 107
"Fred Billig was one who accepted the merits of thermal compression and
gave his own analyses. He proposed that at Mach 5, thermal compression could
increase an engine’s specific impulse, an important measure of its performance, by
61 percent. Years later he recalled Ferri’s “great capability for visualizing, a strong
physical feel. He presented a full plate of ideas, not all of which have been realized.”39

39 Journal of Spacecraft and Rockets, September 1968, pp. 1076-81. Quote: Fred Billig interview,
16 October 1987. Folder 18649, NASA Historical Reference Collection, NASA History Division,
Washington, D.C. 20546.

Well the devil is always in the details isn't it? If imitation is the sincerest form of flattery and it was such a good idea, why didn't Billig or someone else make use of it? If one reads the '68 JSR reference you will see Billig's analysis/evaluation of the thermal compression process is of the most very idealized theoretical sense. Nothing wrong with that, as long as one recognizes this, similar to say the Carnot efficiency for any heat engine.The idealized analysis uses a two stream stream approach where the thermally compressed stream only interacts with the main fluid stream through the engine via the "boundary" between them. There is no mixing between the streams. So in essence the thermally compressed stream can be thought of as a simple variation of variable geometry. Now that said, start taking a look at all the practical the real world engineering features and processes required in trying to implement this idea in a real device. Injection, mixing land Rayleigh losses in the total stream, followed by reduced O2 content in the total stream. But it's hard enough to get the fuel to mix and burn in an efficient manner in the combustor, now you need to do this in the faster moving inlet flow where the temperature and pressure are even lower than in a normal combustor. Rayleigh losses also scale with Mach number. This is seen in the JSR paper where the 61% Isp increase at Mach 5 is reduced to only 3.5% at Mach 12. Moving into the combustor, you have all ready burned a fraction of the O2 in the inlet and haven't made any thrust yet. However, you have made your job of injecting and mixing and burning fuel in the combustor harder because it is harder to find and mix with the remaining O2. Same problem as one is challenged with in staged injection schemes required at low Mach to deal with limitations in area ratio schedule in the combustor. It works at Mach 5 because it is relatively easy to make thrust here. Cruise typically requires phi~0.7 or so. Not the case as you go up in Mach and the ratio of the amount of energy added to the flow due to combustion becomes a smaller fraction of the total energy of the flow. The formula of M2/89 is typically used here to express this ratio.

On top of all of this now consider the system level costs, remember a hypersonic vehicle is an MDAO problem. It needs a whole other fuel injection and control system. Start to see the real picture? Has it bought its way into the system?

Good inputs.

I am looking forward to playing with this thermal compression idea, in retirement.

And then at the end you reference the "Pioneering scramjet developments by Antonio Ferri"
paper by John Erdos and Lou Nucci. where they mention Ferri's advanced MOC based CFD tools,
and his cone-shaped design, Which is very interesting.

So you kind of beat me down with a stick, and then say go read Erdos/Nucci - a carrot !

Just kidding about the stick.

How cool would it be to have a Lab and just work on this stuff all day, every day !!
And then go build stuff and then fly it !! Jeez ! My vision of Heaven !!

 

[shockonlip]

You may be correct, but I encountered a testimonial of Tony Ferri
by Fred Billig which I took my comments from:

"Facing the Heat Barrier: A History of Hypersonics"
by: T. A. Heppenheimer

pg. 107
"Fred Billig was one who accepted the merits of thermal compression and
gave his own analyses. He proposed that at Mach 5, thermal compression could
increase an engine’s specific impulse, an important measure of its performance, by
61 percent. Years later he recalled Ferri’s “great capability for visualizing, a strong
physical feel. He presented a full plate of ideas, not all of which have been realized.”39

39 Journal of Spacecraft and Rockets, September 1968, pp. 1076-81. Quote: Fred Billig interview,
16 October 1987. Folder 18649, NASA Historical Reference Collection, NASA History Division,
Washington, D.C. 20546.

Well the devil is always in the details isn't it? ...

I have a little more time now to talk now.

Remember DSE that this is originally about a JHU-APL guy (Billig) giving some kudos to a
NASA Langley guy (Ferri). That was the purpose of my T. A. Heppenheimer reply.

Then you went off on your interesting thermal compression viewpoints.

But I must respond to a few because they leave the wrong impression.

>If imitation is the sincerest form of flattery and it was such a good idea, why didn't Billig or
>someone else make use of it?
They did ! One was the subject of your original post on this thread. It was proposed by
Marquardt as a HRE candidate for X-15A-2!

The first actually was for the USAF funded, Scramjet Incremental Flight Test Vehicle (IFTV)
program initiated in 1965 for flight (after boost) at 5400 fps at 56,000 ft altitude, with
acceleration to at least 6000 fps. It was killed before completion of ground test and no
flight test was done. ("Scramjet Engines: The First Forty Years", E.T Curran).

The second was under USAF sponsorship in 1964-1968, the low-speed fixed geometry
supersonic combustion ramjet. Designed to operate from Mach 3 to 12 without
variable geometry. It also used thermal compression. Various inlet and engine models
were tested under this program. ("Scramjet Engines: The First Forty Years", E.T Curran).
Mr. Curran does not say if they were successful, but this must be the project that
NASA was a little miffed with Ferri/Marquardt about, as described in Hallion's
"Hypersonic Revolution- Vol II", where Hallion said that NASA was rather disappointed with the
blandness of the HRE proposals except for Ferri's thermal compression proposal. But, they
were disappointed that he (Ferri/Marquardt) was bidding the same engine design
that Ferri was working with the USAF on.

Curran also mentions the Russians were very interested in Ferri's approach here.

So I think we have shown that there was interest. Indeed, money was spent.

So I like your statement of some of the problems DSE and I like Ed Curran's summary too:
"In these various engine designs, the vision of Ferri in creating concepts that would
tailor the aerothermodynamics of fuel injection, mixing, and combustion to the desired
engineering features of the engine was apparent. The difficulties of engine design with the
available computational tools of that time period , together with the twin challenges
of assuring controlled heat release and avoiding internal flow separations, in a very
demanding ground-test environment, made the timely achievement of such an ambitions
undertaking very difficult indeed."

I believe thermal compression could be a feature of future scramjets. I think that the
sensors and controls of such engines WILL be in future scramjets !!

As always, regards!

 

[DSE]

Curran also mentions the Russians were very interested in Ferri's approach here.

So I think we have shown that there was interest. Indeed, money was spent.

Money was spent when Ferri himself was pushing the concept, nothing since. That was my point. As to the Russians or others such as the Japanese, or even the US borrowing others ideas, that's always the case. Specifically the Russians appear to have borrowed the Langley Opposite swept sidewall/strut inlets and the Japanese copied the Parametric Strutless scramjet and possibly the Three Strut Scramjet concepts.

So I like your statement of some of the problems DSE and I like Ed Curran's summary too:
"In these various engine designs, the vision of Ferri in creating concepts that would
tailor the aerothermodynamics of fuel injection, mixing, and combustion to the desired
engineering features of the engine was apparent. The difficulties of engine design with the
available computational tools of that time period , together with the twin challenges
of assuring controlled heat release and avoiding internal flow separations, in a very
demanding ground-test environment, made the timely achievement of such an ambitions
undertaking very difficult indeed."

I believe thermal compression could be a feature of future scramjets. I think that the
sensors and controls of such engines WILL be in future scramjets !!

If you believe advanced computational tools will be the salvation, you might consider that they may also make the problem harder when you add real or more detail. By analogy in PIONEERING SCRAM JET DEVELOPMENTS BY ANTONIO FERRI one finds the following statement, on p 4:

On the other hand, at some suborbital speed (depending on the trajectory and the vehicle design) the fuel flow rate required to cool the structure begins to exceed the stoichiometric rate required for acceleration. In Ferri's design, this occurred at about Mach 22, as shown in Figure I0, with the inlet and nozzle surfaces being the primary contributors to the cooling problem.

Today's state of the art analyzes have that cooling requirement overtaking stoichiometry at nearly half that Mach number.

 

[shockonlip]

I guess on this matter we just disagree DSE.
Thanks for your inputs though.

 

[DSE]

A more recently added Ferri thermal compression paper on NTRS.

Title: Heat conduction controlled combustion for scramjet applications Online Source: Click to View PDF File [PDF Size: 1.1 MB] http://hdl.handle.net/2060/19740021104 [/t][/t] Author: Ferri, A.; Agnone, A. M. Abstract: The use of heat conduction flame generated in a premixed supersonic stream is discussed. It is shown that the flame is controlled initially by heat conduction and then by chemical reaction. Such a flame is shorter than the diffusion type of flame and therefore it requires a much shorter burner. The mixing is obtained by injecting the hydrogen in the inlet. Then the inlet can be cooled by film cooling. Collection: NASA NASA Center: NASA (Unspecified Center) Publication Date: JAN 1, 1974 Publication Year: 1974 Document ID: 19740021104 Accession Number: 74N29217 Subject Category: PROPULSION SYSTEMS Report/Patent Number: NASA-CR-132446 Contract/Grant/Task Number: NGR-33-016-131 Publication Information: Number of pages = 42 Language: English Subject Terms: CHEMICAL REACTIONS; COMBUSTION PHYSICS; CONDUCTIVE HEAT TRANSFER; DIFFUSION FLAMES; FILM COOLING; HYDROGEN; PREMIXED FLAMES; SUPERSONIC COMBUSTION RAMJET ENGINES Accessibility: Unclassified; Publicly available; Unlimited; No Copyright Document Source: CASI Updated/Added to NTRS: Jun 13, 2011