some comments on this video are filtered out by RU-vid ( Google ) so sorry if you see that. It's not me.. so please comment and I'll do what I can to post the comment. I'd guess that Google classes some comments as potentially terrorist since the scramjet is the next wave of tech to be used on American drones. This would of course make them mostly invisible to radar and so fast they couldn't be stopped
6:15 that model looks to me like a ramjet not a scramjet. I am no expert just what i learned from your video. I mean the geometry looks exactly like a ramjet.
You are looking at the aerospike on the front of the engine unit and mistaking it for a ramjet intake. A ramjet intake must be movable in order to adjust the intake flow of air so as to allow proper compression just before the combustion stage. That aerospike is there to reduce drag and help push the flow of supersonic air into the intake. There are 6 scramjet engine units arrayed around the aerospike - all with no moving parts... which is the defining factor of a scramjet. What I'ld like to see is if we could possibly create a scramjet from super-high temperature ceramic components, accellerate it to operating speeds with a rocket, and power a launch vehicle into space from a ground launch .... it would be a 1-time use launch vehicle concept, but if it's powerful enough it could put the shuttle or other reusable space vehicles into orbit much more cheaply.
Makes sense...delete replies and just leave the video. That's what I'd do if i didn't want the public to know my shit. Like posting your nudes on a billboard and only stopping news people from broadcasting it so no one will see it. I am so smart. S-M-R-T - Homer J. Simpson
Let's not forget turbofan engines. They have another set of fan blades. Let's say there are 10 sets before fuel is added to the compressed air to create thrust. In a turbofan engine, another set is added - to make 11. Just that set is routed around the other 10 and added at the end for additional thrust.
@Harry M turbojet engines is the broad terminology, high bypass and low bypass(used on fighters) turbofan engines are all types of turbojets, even turboprops are a type of turbojet engine
What interested me the most was the fact that while Queensland University has done so much work on this concept. The actual state of scramjet research is buried in the depths of "Classified" information probably in Russia and the United States.
All I'm saying is look at the Blackbird. That thing is a mechanical marvel and was built during the cold war. Rockets however made putting those engines on planes obsolete. Why spend hundreds of billions if not trillions putting it on a plane when you can build a rocket for a fraction of that and shoot said plane out of the sky Or destroy the entire air base that launched the plane in minutes and hours? I would love to see what every nation really has at least just from a curiosity stand point.
@Wai too Low anything in front of it is history for the first minute or so of combat. Could you imagine reloading every individual metal storm barrel full of all those rounds every time you want a couple second burst? Autocannons will always be a better alternative.
They're still around, they just went insolvent. Only a few companies ended up buying all their patents and technology, so the teams are still together.
Good lecture. I’ve worked over 40 years for the US Department of defense in the acquisition of weapon systems and one rule in certain, stealth is cheaper than speed
@@HTV-2_Hypersonic_Glide_Vehicle I have worked for the missile defense agency since 2006 and the Air Force since 1982. My view on hypersonic weapons is they are limited in use and over hyped by both sides. The vast majority of ground targets costs far less the the hypersonic weapons that targets them.
you really should look at the Sr-71 engine diagrams, the are normal turbine jet engines but with 6 bypass tubes moving air from the leading cone to the exhaust making them ramjets. As well as being able to keep the perfect pressure/speed mix by varying the cone distance.
Doodley - I seem to recall that the inlet spike ("cone") was positioned to trap and diffuse the normal shockwave inside the engine air inlet. An "un-start" is when the shockwave popped out the front of the air-inlet, and in the early (pre-computer) days of the SR-71 program, an un-start was a serious hazard. Later computer controls all but eliminated the problem.
I don't know why, but for some reason RU-vid has been recommending a lot of videos about aerospace engineering and the SR-71 to me lately so I was also thinking about the turbo-ramjet of the SR-71.
I don't know why, but for some reason RU-vid has been recommending a lot of videos about aerospace engineering and the SR-71 to me lately so I was also thinking about the turbo-ramjet of the SR-71.
I know very little about jet engines period and came here as a novice. Fully understood your description so within that paradigm, well done. Aussie Aussie Aussie!
Excellent presentation. He made it easy to understand. It will be challenging for the material engineers to come up with materials to handle the extreme heat issues.
Sintesi: ottima spiegazione della differenza tra turbojet e autoreattore in pochi minuti. Chiari i concetti espressi con linguaggio appropriato. Livello accademico.
@Didddin duuu nufffin Wakanda enn shiiieet no one uses miles feet or inches, except a world superpower, the entire aviation industry, and many more lol
Excellent lesson and presentation, Edwin, thank you. Question: How dense is the H2 and plasma (protons and electrons) above the mesosphere? I'm thinking a scramjet for this stage would only need an oxidizer, if the fuel around it is sufficient.
Notice that it's actually dynamic pressure that counts for thrust, not static pressure. So it pays to take advantage of synergetic motion of the exhaust gases, and the mechanics of supersonic fluid flow.
As a teenager growing up in Folsom Ca. Right next door to Arojet rocket plant, you could hear them testing rocket motors ( normally solid fule ) some liquid motors, All the time. But for a couple of years they were doing development work for Boing aircraft on a Hybrid Scram jet motor, that ran on liquid hydrogen. They were trying to develop a commercial plane that would replace the Concorde. They were shooting for N.Y. to Tokyo in 60 minutes @ Mock 7. Every time they fired it up there was NO Mistaking the noise it made, + The duration of run time... the longest run time of Rockets was 30 seconds, most under 15 seconds, But that Scram-jet was in the several minute range. Usually 2 to 4 minutes, and the closest description of it's sound was that Horrible t.v. show Air Wolf when they hit the turbo button and went Super Sonic .... Never will forget that sound...
how do people put a thumbs down to a video that is talking about a concept that was tested and verified? just shows that no matter what, theres always haters out there.
Ummm. The only application is military. The kinetic energy gained is going to be lost by atmospheric work at the end. The Saturn 5 rockets used multi-story buildings of fuel. When the mission was over and back on earth all of that potential energy had been lost. Economically there is no business reason for that wastage. therefore what is the reason for such high speeds....slingshot into low orbit... Or sneaking up on some third world country?
oldhoboman L “The only application is military.” You sure about that? You could use this as a launch platform for sending satellites into space (military or commercial). This technology can not only help beam you more data (ex. your stupid Instagram feed) but also keep your dumb ass safe from shitheads around the world
This lecture demonstrates perfectly what I've started to many detractors for a long time, that the SR71 was capable of much more than its stated Mach 3.2 speed. It's my contention that the SR71 most likely went into a turbine engine idle condition around Mach 3 and then adjusted the inlet cone and afterburner section to perform as a pure ramjet. This capability would give the SR71 a possible speed of at least Mach 6. My thoughts are Mach 7.1, hence the SR"71"... just sayin 😉
As long as the projectile course of a rocket is in an atmosphere, the use of alternate methods of propulsion for a rocket is a possible option because the use of jet, ram, and scramjet technology increases the potential to reduce the material requirements needed to accomplish whatever task you are shooting for when utilizing a rocket.
Great clip, nicely explained for a non technical person like me. Perhaps we need to look at different ideas of propulsion. Electro-mag, gravity, who knows but rockets are old tech. Somewhere, I suspect some military contractor must be looking at some really interesting forms of propulsion.
Excellent video. May I suggest that when talking about speed in general you also keep in mind that most "proper" Engineers who work in an International environment find the use of the French "MKS" or Meters, Kilograms, Seconds to be an abomination. Especially the use of Kilometres when it comes to speed. I suggest "miles per hour" is far more widely used and by some of us less hated as a cause of confusion and errors. The quality of your video makes it worthy of an International audience beyond the narrow (but very lovely) confines of Queensland, Australia. Party on.
Supposing a ramjet were attached to the nose of a projectile fired from an electromagnetic cannon? As the projectile were moving through the air, the ramjet would detach and continue via its own power to Mach 6. Upon reaching Mach 6, a scramjet attached to the nose of the ramjet would detach and continue via its own power to Mach 10+. Sounds like a good idea!
engines of the SR-71 are a bit like this concept - with bypass technology - but I'm sure the concept can be taken much further. I'd welcome an aircraft that entered orbit and reached England from Australia in a few hours rather than the grind of a 30 hour flight as now :)
You could stack planes like stages of a rocket: first, a big turbojet starting from nothing and picking some height and speed. Once its fast enough for a ramjet, it disconnect affirm the turbine first stage and does his part, then the scramjet gets going, disconnects and continues on! First and second stages return to the airport. On the other end of the trip a ramjet awaits, scramjet "lands" on it, then the combination is met by a turbojet who's like a flying aircraft carrier for faster jets! Everything lands together, people come out and go to the hotel. Or maybe they can be dumped into the ocean cause to land is a drag and its too much fun to fly around combining and separating in the air! That huge tubojet can be refuelled in thecsir and so the whole thing never need to touch the ground! Wow. I wish I was 30 years younger and could go to QU and become a rocketman!
I can think of some other tech (already out there) that when combined with this ..would certainly tickle Mach 14 and possibly beyond :) Congratulation to all involved. Stay on that leading edge of technology, I truly respect people like this. Bravo!
Thankyou so much this was the fist time I understood the design and working properly .. now i can make a super sonic jet into hyper just by adding a part .. oo wao i love my ideas.. then it can really make a scramjet go from 0-12 /// awesome thankyou
When he said a jet engine can get you up to 1 KM a second, it really put the speed into perspective. A person running at full speed can do that in maybe 5-6 minutes. A car on the highway does that in about 1 minute. By the time you finished reading my comment that plane would have already flown about 20 KM.
The forcing cone on the SR71 was automatically adjusted forward or backward in relation to speed. The engines of the SR71 were made from materials not found in service jets. More so, the fuel consumption was reduced as the speed was increased. He uses a lot of facts to disinform what we’re capable of. We have vehicles that can exceed Mach 14.
This professor explain these super interesting subjects so well that I fell like I am a genious. Then I stop the video and fell like I'm the dumbest guy on earth again.
Edwin Henry Blachford - What an EXCELLENT presentation . Correct me if I'm incorrect , but the ram jet / scram jet technology of the 60s' - 70s' was considered to be relatively "low tech" compared to jet engines . I worked for a company which manufactured experimental ram jet / scram jet engines . From what I came to understand - The fuselage of missiles and aircraft at the time couldn't structurally withstand the G forces generated by Mach 4 and above ... neither could a pilot . The structural integrity of missile and aircraft components has obviously improved with modern materials and many countries are returning to scramjet technologies . All the best to you Mr. Blachford and Thanks once again .
yes, engine development is just one piece of the puzzle. Deceptively simple indeed. Sustained flight at Mach 8+ requires special technology. Perhaps the solution has been to divert hypersonic airflow to prevent it from contacting surfaces internal and external, thus avoiding the need for shielding and expensive materials.
Thanks for your reply Mr. Blachford . Yes ... modern carbon fiber and ceramics have been the answer .Not much research into an ionized atmosphere which precedes the control surfaces . Similar , but quite different to hydrodynamics and torpedo technology in which a torpedo "flies " within its' own created atmosphere which precedes it . The velocity of the craft is measured and simultaneously ... servos control the intake of ambient air / oxygen to the engine . A "swirl pre warmer " using a parabolic curve and that focal point for the engine intake might help . As far as external control surfaces , have no idea . Titanium or tungsten lead surfaces + ceramics as used in a space shuttle .
Thankyou for the excellent technical bteakdown Sir....fascinating stuff. Now I understand why at ADELAIDE INTERNATIONAL RACEWAY....back in the 1990's .. the "F4 Phantom" powered JETCARS were doing "quarter mile" runs under 1 second !!!!
Much as i want to believe you, no. As far as I am aware, the fastest rocket powered dragcars never broke the sub 3 second quarter mile barrier. Additionally, whatever powered the F4 was a turbojet, which is not what this video is covering. And top fuel dragsters, despite ridiculous acceleration, do not come close to sub 3 second runs either. So, not entirely sure what you saw all those years ago.
jets fine with me. mach 2-3 is OK. I don't guess I'll need to go any faster! but I guess we can throw a big old scram jet engine on there also. 0 to mach 10 in 2.5 seconds or less! I guess it be a seat. two wings. engines and a huge fuel tank. and let's go for the world record! not only top speed but the quickest also! like drag racing with jets!! I know I'm dreaming! only a country can afford to drag race jets! great video. I wondered about these. I always was interested in these engines. but never had and sources of info growing up. I even tries building a jet engine as a kid. but all I really did was set some cans on fire! thanks. great info!
Since air is compressible and so there is a limitation of how much we can push against the air without losing thrust by over expanding it at the outlet. A multiple out put of the same engine and the geometric arrangement of it may help improve efficiency but for hypersonic speed we need more with something like inertia system that could help to develop extra thrust without over expanding air
Hmm, I guess the goal would be a seamless transition from turbojet concepts to rocket concepts all in one engine. In which the traditional turbojet is fitted with a scramjet bypass as a function of the afterburner, in which of itself contains the rocket mechanisms for outer space travel. An engine that adapts to it’s environment, though quite complex due to the integration of the three systems at once, if not compounding the cooling issues and the limits of the combustion process
the concept at the moment is rocket launch to Mach8, initiate Scramjet. Suitable for missiles mainly and vg for such due to the extended range resulting from no oxidiser required/this is where development is at. Then next a composite engine is the Nirvana, logically turbojet to Mach3.5/close compressor/into Ramjet mode (eg SR71)/get to Mach8/into Scramjet mode/get to Mach14. Such a vehicle will be the way most spacecraft would be launched.. piggybacked onto the Scramjet composite. The main barrier is heat at hypersonic speed/most metals melt/most sacrificial surface systems haven't worked. The Queensland Uni is developing the laminar/isentropic flow technology that overcomes this which is why the US Govt has bought into the program. It only takes one idea to make things work then everyone else can develop the crap out of it
Well, there are air-breathing rockets. They're combustability agnostic, using both fuel and oxidizer. But the heat of the rocket motors expand an airflow through the rocket for bonus thrust.
I would like to comment about your ramjet/scramjet engine and I think a method for adjusting the compression for proper combustion. You have shown a center-position airflow restrictor that is not moveable and I think that is the key to adjusting compression. Make your restrictor moveable, such that it can be used to adjust the compression to a suitable level. And consider using different types of fuel for flight at different altitudes. And consider using a ramjet engine at take off speeds as they originally did post WWII.
Really you could do an inlet system that could move through all three stages. The sr71 already somewhat does this. As the plane gets fast it's need to slow the air down becomes less significant and you could have the inlet move to a point to stop the turbo jet from receiving any air and have it full convert to a ramjet then it gets tricky how to design it to become a full scram jet. Most attempts are using rockets to get the vehicle up to hypersonic speeds.
Dude you should be working for the DoD, move to Long Island and get a job at a DoD aerospace company. This is a lot of information for a lot of countries that don’t have the knowledge
At some point you'll have an issue with flame propagation inside the combustion tubes of the scram jet design, where by the only way to rectify is to increase the length of the combustion process or accelerate it.
Scary stuff. Torpedos flying at mac 10-14 means that people could be murdered in massive scale without seeing what hit them. I believe that starting with ramjets there is no way to intercept them due to their speed.
Performance specs for an MD F-15 and F-18 are mach 2.5 and 1.8, respectively. Are these speeds achievable only at high altitudes for these aircrafts? How fast would you estimate their top speeds to be at sea level?
I have a hybrid engine idea. A normal jet engine with vents that could be opened on the side to bypass the turbines. These vents would open after passing mach 3 or 3.5
