Nicely done. Thanks. Former USAF officer here. Trade offs. The issue is one of materials science. Rotational detonation engines (RDE) provide much greater pressures and thrust but you have to have the alloys strong enough to take the high temperatures and pressures without failing. Those types of alloys increase cost and very likely weight. Have served in the Tactical Air Command, I am fighter biased, but RDE technology may be better suited to 1) missiles that make one trip to their target; and 2) naval vessels that have less concern about weight of the propulsion systems. Air superiority depends on mission readiness, availability, and turnaround time. The more sophisticated the jet, the longer and more complex the maintenance. That increases turnaround time even if you have the tech, parts, and highly educated human capital to sustain such intense maintenance. That is difficult in a secure environment far from threats, but much harder closer to combat. As noted, these jets would be ungodly expensive as would be parts and maintenance. That leads to fewer jets and fewer training hours for the pilots-availability and readiness issues. I am not saying this is not a potentially revolutionary technology, nor am I saying that we should not deploy it where it is better suited. What I am saying is that we have to think about full lifecycle technical trade offs, costs, logistics, maintenance, availability, and readiness to best achieve our strategic and tactical objectives.
I used to know quite a few DARPA people (not all were engineers) and there is a common saying they have. 'About 50% of the things that are said to be impossible really are'.
Icarus didn't have the Federal Reserve! I'm certainly no engineer but I'd say 50% of things said to be impossible aren't financially viable 75% of the time lol.
I used to know a bunch also......but for only three years. I got attacked by crickets in Canada while listening in on some bears. Microwave pinball can really get the ears ringing.
The proper, simple, explanation for why detonation engines might be worthwhile to pursue, is this: All thermodynamic engines get their energy from fuel being burned with oxygen. That's the start, and it's the same for all engines. There is not 'more' energy available for some engines than others. It's only the chemical energy in the fuel, a fixed amount. Same for all. What is not same for all, is how much of that energy, the engine is able to convert into work. This is why we have the concept of thermodynamic efficiency. (With rocket engines and jet engines we also have propulsive efficiency, but forget about that, because this does not concern that.) Now it happens that all thermodynamic engines extract their work from the ' *_Expansion_* ' phase of their working gas, which typically - and particularly in this case -, is the same as the combustion gases. The greater the expansion, the more work = useful energy, is extracted. Now we come to the first point: You can have more expansion if you first *_compress more_* . This is why we have Diesel engines. It's why the most advanced jet engines have pushed to 80:1. It's why SpaceX is pushing for +300 bar in their Raptor rocket engine. But, here's a crux: As the fuel burns, the combustion gas expands (in *jet* *engines* and *rockets* , in piston engines you of course get the combustion *_before_* expansion), because the expansion moves faster than the burn reaction. So you don't get to suck all energy from the max, theoretical, possible expansion. What if you could have the reaction (fuel burn) take place before the gas expands? This should result in better fuel efficiency. And it will be achieved if the reaction (fuel burn) is faster than the gas' expansion. And that is what we call *_detonation_* . The full burn first, then the expansion, instead of expansion during the burn.
Didn't think this video could be better. Your explanation supports why Japan, Australia and anyone frankly able to produce this technology would. It's applications are beyond military and aerospace.
@@user-ee1fn4vt8b During Deflagration (gunpowder, smokeless powder, petrol, etc.) the burning front moves through the fuel/air mix below the speed of sound in the combusting material or the working fluid. During detonation (TNT, RDX HE generally), the burning front moves through the material at greater than the speed of sound in that material.
You may not be a scientist but you explain pulse detonation and the difference between a internal combustion engine and this process better than most science articles I've read about it. I'm a science and technology geek and your information is always spot on and accurate something I applaud you for. You take the time to get the details right. Your humility leads to higher accuracy.
It's perfectly normal as scientists are generally expected to do scienscy stuff instead of being educators. Sometimes a person can be both, like Anton Petrov or Stephen Hawking, but it is not a must. Division of labor and specialization.
I worked with Dr. Fred Schauer on the worlds first self-aspirating PDE in the early 2000's, which is later developed to what you see at 7 minutes. You can basically eliminate the pumping losses of a compressor section, and get MUCH higher exhaust velocities. We built it out of a cylinder head on a shoestring budget. I thought this tech never panned out, but this concept is great! The donwside...this thing sounded like a jackhammer, but as loud as artillery. An RDE might also make a decent tip jet on a helicopter or prop.
@@oleran4569 Yeah- Oldsmobile quad-4 cylinder head fed the detonation tubes. A motorcycle engine was needed to run a compressor to force air through that restriction though.
It's actually really interesting how the energy is extracted makes a big difference. We have detonation in diesel engines but it's been a struggle to get it to work in gas. I don't know if the entire charge detonates in diesel engines even. It might be interesting if it could be made cheap enough eventually to offer an option for vehicles. It could make the transition to lower carbon power sources easier. Cool video. I would like to hear the one about China as well. Yours is the only one of these style channels that I feel gives quality information and isn't tacky. Keep up the good work.
Actually, none of the charge detonates in diesel engines. It burns. You never have a supersonic combustion front or shock wave inside a diesel engine (or at least if you do, you're having a really bad day). That's also true in gas engines - the goal to get compression ignition gas engines to work is to get them to compressively ignite in a controlled way without generating a detonation wave, because detonation waves inside piston engines tend to break things.
As stated above, there is no actually detonation going on in diesel engines. The flame spreads slower than the speed of sound in the fluid. It merely deflagrates.
My understanding is that gas engines have a singular flame front spreading out from the spark plug, whereas diesels have many smaller flame fronts detonating throughout the combustion chambers.
@@taylorc2542 It's a nitpicky issue of terminology, but an important distinction. Often, when the fuel-air mix is ignited in an internal combustion engine, people refer to it as a detonation, because it's a very brief, loud, powerful burn. But technically, it's a "burn", and not a detonation. Imagine pouring some fuel on your BBQ grill. you light it, it goes WOOSH! with a fire ball, and your eyebrows are ruined. That's a burn, or as the video is called it "deflagration". If it were a "detonation" it would go BANG instead, and instead of looking like a miniature napalm experiment, your bbq would look like a miniature fuel air explosion, and there'd be pieces of your grill falling 3 blocks away. possibly pieces of you too :P Anyway, internal combustion engines don't detonate, even if it is fast, it's not supersonic. And yeah, a lot of car people might call it a detonation, but not technically the right term. If it were a true detonation, then the piston would move down at supersonic speed. And nothing about the block, crank, or piston is really designed to handle that.
The way something burns makes all the difference. There's as much energy in a ham sandwhich as there is in a stick of TNT, or a similar weight of C4. The differences are all in how rapidly they burn.
Heard about it 5 years ago. From what I remember they had huge problem with two of those rotating shockwaves (there always has to be at least 2) bumping into each other causing whole thing to be unusable
DARPA announced they're starting an 18 month design phase with various contractors. That will be followed by an 18 month full scale test phase. So yea...I think they ironed that stuff out :) edit:words
Any missile technology is good right now. That missile truck the USAF wants to build will seem viable. Having one plane dropping 60 plus cruise missiles with increased range make it more viable. Of course it will be paired with other aircraft to locate targets. Forgot the name of the units but the Wild Weasels was one.
@@Future-Preps35 WOW! They should've just asked You instead of wasting years of Their lives on the research! You don't get the concept. It works like a gas turbine but instead of combustion there's detonation
Definitely do a video on China’s anti-ship weaponry and their “1,000 mile radius”. People make them sound invincible, and I’d love to see your breakdown of their strengths and weaknesses.
Your excellent channel definitely gets a score of five Ian's out of five for weaponry youtube channels. (Five little pictures of Ian McCollum giving a thumbs up) Subbed and chit.
I got excited when I saw the notification (for which I had been waiting) and what the topic was. Awesome video. At least 3 times I went to click the thumbs up and forgot I already had.
Great video, as always, Alex! Have you thought about doing a video devoted to the LRASM system? The more I learn about them, the more sci-fi-is-now they seem to be. Pack 'hunting' anti-chinese ship weapons. Their programming behavior is very, very interesting and I think would make a great video!
I read of a future scenario where the f35/22 control 10s of drones in a forward position while they are in the rear. Couple that with drone refueling and the navy and fighters will be somewhere over the horizon in a battle. Great analysis!
I thought that “afterburners” went out with turbo jets.Turbofans, if so equipped, have “augmenters”, instead of afterburners.This is an important distinction because in addition to what goes through the combustor, augmentation uses clean unburned air bypassed AROUND the combustion chamber. This cools the combustion chamber allowing it to operate at higher pressure ratios AND provides fresh air to the augmenter. All modern fighters use augmented turbofans these days.
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Love the presentation, I understand how this would work in missiles and aircraft, but I'm not how this would work in ships. I understand that the engine produces thrust, I'm not sure how it would produce torque however.
Do you need to produce torque? You could use thrust throttling and vectoring (like coast guard jet boats) to steer, rotate in place, even move sideways, power brake, go in reverse. Don't even need a rudder.
Many naval ships already use gas turbines (like in a helicopter). The rotating detonation would replace the combustion chamber of the turbine engine. If the technology works as theorized, all gas turbines would eventually be replaced with versions that detonate fuel instead of deflagrating it. (BTW, the turbine connects to an electric generator or gear box.)
We used to call RDE "ultra compression" and knew that it was much more efficient than a traditional design, but it isn't exactly zero maintenance. Parts wear out so quickly that it makes for a disposable engine core with all of the stress fractured components.
I had this idea years ago also and its perfect for long range stealth aircraft because of the reduced heat signature of the thrust.. and commercial airliners with vertical takeoff and landing..
Frreeman Dyson used a simular idea or technology to use a Nuclear Powerplant to power infrared waves on to a metal tungsten rod that reacted to infrared waves to create a non 02 detonation and create a detonation pulse that would in theory provide a infrared magetic pulse engine. He worked for General Atomics at the time and this was supposed to be used for the Orion Space Craft slated to go to Mars. I do not know if we ever went. I can only dream we did as an explorer. This is like sailing a ship to a new far distant land.
How loud are these engines compared to conventional jets today? Doesn't seem like you'd have a lot of means to do baffling. Not a big deal for missiles or even planes if they're going Mach 5. But for ships, does the engine stay above the water? Or is it detonating in the ocean? Water carries sound very far and fast - and if there's a stronger pressure wave (ie: louder), you could both increase detection range and probably kill or disorient a lot of fish and whales and other marine life (already a problem today). I haven't looked into it, but just curious.
AFAIK, it breathes air and will turn a turbine shaft. I believe the intent is to just replace the current engines with something more efficient. A detonation wave travels at supersonic speeds, so it would make sense that the engine's fundamental frequency would be well above ultrasonic. If so, it should be easy to create isolation mounts.
It's a very good question, I would imagine such an engine would be LOUD and dangerous. Metal and water and air will as you know propagate a wave, generally the denser the medium the faster the wave can travel, and being supersonic I can't imagine that would or could be used in water, it would be like a weapon itself !
@@psycronizer How could the engine be used in water? It requires air (or gaseous oxygen) to operate. Yes, it creates an exhaust gas stream, but that isn't fundamentally different from current turbine engines. So if you were committed to using a high-speed exhaust gas as a weapon, you could do it now.
@@psycronizer well, it doesnt matter that you cant imagine it. the guys at DARPA did imagine it and are making it happen so in a few years when this is common tech, i wonder if you will remember saying this wont work
Hey great vid ! Just to add in more technical detail the reason detonation creates more thrust from the same amount of fuel or 'specific thrust' is due to the increase in thermodynamic efficiency as seen in comparing a Fickett-Jacobs and Brayton cycle P-v digram. This is due to detonation wave moving at sonic velocities creating a shock and pressurising the reactants without the need for a piston/compressor blades. this is why its so called 'pressure gain combustion' although when looking at the cycle as a whole no thermodynic laws are being broken as the name suggests. Also i think some italian guys have already flown one on a model rocket as well as mbda looking into this concept recently, i alos know of a paper detailing the incoperation and running in of a RDE combustor in a gas turbine. Can source if intrested.
I think these engines were tried by Heinkel Hirth at the same time as von Ohain Jet engine was being developed in the 1930s. They were referred to as 'constant volume' jet engines instead of the 'constant pressure' types we know. A compressor filled several combustion chambers in turn using poppet valves. Sparking plugs ignited the mixture and the exhaust propelled the aircraft. They operate at much higher pressure and temperature ratios. Mentioned in Anthony Kays "German Jet engines and gas turbines"
They were pulsejets, as described at the beginning of the video, and they operate at absolutely miserable pressure and temperature ratios, producing absolutely miserable thrust and efficiency.
@@wagnerrp Constant Volume Jet engines are not the same as pulse jets. Constant volume engines used compressors and poppet valves to admit air to a number of combustion chambers, close the valves and ignite. Another poppet valve would then open to release the gas over the turbine. They are theoretically much more efficient than standard constant pressure jet engines.
@@williamzk9083 A pulsejet is a constant volume jet engine. You're just describing a different type of jet engine that honestly sounds like an nightmare for maintenance and cooling. Pound for pound, reciprocating engines are shit for reliability, and the lack of opportunity for film cooling in the combustor means your materials are going to have to have to carry the full thermal load of combustion directly, while simultaneously receiving tremendous cyclic loads.
Rotation Detonation Engines work on basic thermodynamics: the higher the starting burn, the more efficient the engine ought to be. What stops the highest temperatures: materials. Diesels have to use inter-coolers after the turbo-boost just to save the engine. From a purely thermodynamic point of view, the ideal engine wouldn't have one. (Highest efficiency would degrade unit specific output -- less HP.) RDE hopes to fuse the episodic burn seen in ICE engines -- where the burn temperature is quite high compared to the containment metals -- with the flow through seen in open Brayton cycle engines. ( gas turbines ) If RDE geometry can be solved, the Big Change would first show up in the use of MUCH cheaper metals for turbines. RDE tech would not change the nature of after-burners. They'd still be fuel pigs. For ultra-speed applications, we've already hit the wall in terms of materials. RDE -- it is hoped -- would allow super exotic performance when exotic materials were employed. It'd be like a rocket motor that does not need regenerative cooling. (The latter chills expansion gases that you really wish to keep super hot.) Such wasted thrust is most evident in the classic NASA footage of the Saturn V at lift off. A skirt of un-burnt propellant shoots down -- hiding the flame -- until about 2 meters below the nozzles. Then the gas bursts blindingly white hot. Of course, the whole idea of using naval air against Red China is a joke. As seen in 1945, carriers sail close only to deliver the coup de grace. Red China will be defeated by radio announcement. Once the USN broadcasts that merchants sailing to Red China are suicidal -- no-one will do so. There will be no repetition of the Battle of the Atlantic. (1939-1945) Red China's war industries will collapse faster than Putin's.
The temp issue is solved with the use of inconel 625 nickel allow metal. Spacex and other rocket companies have improved their engines with the use of the metal because it has extreme upper temp limits.
IF they have really solved the technical ceramics crack propagation, this would improve all heat engines a lot. Hundreds of deg higher operating temperatures. Somewhere I've read that the they are testing the first aircraft engines with ceramic blades. This ceramic has nothing in common with the household ceramic.
I'm curious to see if the RDE concept is what would power a potential hypersonic fighter, which I believe you discussed in another video or perhaps on your website. The use of RDE in manned fighters and drones would indeed go beyond next gen.
@@brobasticbroham446 I agree with your premise, that said as technology increases and stealth capabilities are made more compatible i.e. ceramics to increased speed. The need for speed will be incorporated, for it too offers increased benefit. I purposefully used ceramic because I've seen that there's a current push for more reliable maintenance wise and higher temperature resistance radar absorbent material.
@@hansybarra Technology is ever increasing and you bring up a valid point. Currently it's expensive. Check out Rotary detonation engines. This is hypersonic flights future. Adaptive cycle engines are currently being deployed in F-35'S.
Hey, could you do a video or series on the current and near future state of anti air weapons? Which MANPADS do exist, what will replace the Stinger? What is the state of lasers? Which longer range options for ships and on land do exist? What do fighters have to shoot down other planes? What is currently in service or in development, either by government contract or from manufacturers? This would work well as a mini series either by range/type of defense or country of use.
I think DARPA actually just identifies where potential breakthroughs are and provides financial incentives for other groups to yield results. DARPA has many projects of many different fields of expertise, so the projects don't overlap much in terms of the facilities or people actually doing the research. They hosted competitions for self-driving vehicles years ago, but the implementation of such technology in both civilian and defense applications is gradual with many iterations.
Great work as usual... definitely interested in seeing more on China's growing capability to strong-arm its neighbors and what can be done to help those neighbors maintain their sovereignty and counter it.
Yea we really need to stop these barbaric criminals CeCePee. They are so power hungry and want to dominate everyone. Without any regard for human rights or human lifes for that matter. We need every advantage we can get in order to hold them accountable. Otherwise they will do what they want and thats not good since they are only intersted in evil things.
With its top 6 chip manufacturers CEO's being exposed as fraudsters and their chips being fake. I doubt the country can do anything now. 50% of the country mortgage payers ain't even paying anymore and since the housing industry isn't getting more money. That 30% of China GDP is gone. The country is gone in a few years.
One good 'guess' would be sufficient for immediate, negotiated implementation. China then couldn't touch Taiwan, et al. results for nations in the Pacific currently vulnerable to China's recent, open threats.
Thanks for a particularly interesting video. I guess the strategic advances yielded by such an engine development would be relatively short-lived, but that is the nature of all bleeding edge technology in weapons design isn't it?
I'd suggest checking out Perun's recent video about defense procurement. The supercomputer resources that have no doubt been thrown at this problem for decades could be daunting for many nationsto match. And making the best use of the tech requires a military industrial complex that is difficult to match
@5:04 Neither piston engines nor jet engines have "explosions" happening in them, the fuel in both of them burns. When explosions happen in piston engines it's called detonation and it quickly causes damage to the engine. Jet engines also burn their fuel in a controlled manner. I'd guess any sort of "explosion" in a jet would quickly damage both the combustors and the turbine blades. "Subsonic explosions"?!? Check your facts.
I can verify no explosions in jet engines. I worked on and operated GE LM2500 gas turbines engines in the US Navy for 20 year for ship board operations. In starting, the igniters are energized. The fuel is pumped into the combustors. Think of holding a lighter in front of a can of hairspray. Then depressing the little release nozzle on top of the can. That’s a crude way of describing light off. In the meantime a starter motor is turning the compressor of the turbine to produce air for combustion during the start sequence. Once the engine picks up to self sustaining speed the starter motor kicks out. Once the engine is up and running, the more fuel you send to the combustors, the more combustion which increases the exhaust gases to the power turbine. Our ship board engines didn’t have afterburners. Our power turbines were coupled to a reduction gear set thru a high speed flexible coupling and clutch. After passing thru the power turbine the exhaust gases are vented to the atmosphere thru the exhausts. No explosions for normal operation. Now if you do a hot start by going thru start up improperly then yeah you can get a mini explosion which can damage the engine. So maybe that explains the start and operation of a jet engine in a nut shell for those who don’t work on or operate jet engines without getting too technical. Just gives a basic idea. The explosion theory is wack. Because anything sucked into the intake damages compressor blades which at high speed can sheer off and migrate down stream or sling out thru the engine casing. If their is damage to the combustors, it is usually sent down stream to the spinning power turbine which takes out power turbine blades. Either of which is catastrophic to the engine. So no, an explosion is very undesirable.
I think the airline industry would benefit from this technology by save a lot of money on fuel consumption thus lowering the cost of passenger tickets.
Thank you again for your video, , my friend. I recently read an article which, if memory serves, dealt with Toyota and its pursuit and development of a rotational detonation engine which could find application in the company’s automotive industry. Thank you again and have a great week. 🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸
imagine it reaching the private sector as well, electric cars with little generators operating on the principle. the fuel savings per watt and lack of costs related to maintenance and upkeep of combustion engines.... as well as being used by commercial companies who charge customers for electricity... the savings are far more impressive... reducing costs and such... i wonder what the emissions are like for them, i would assume much better and you would never need a catalytic converter ever again.
Is there a question about the theory of decentralizing existing platforms and is whether it is possible to create a decentralized ground-based AEGIS system for the US ARMY and another air transported for the USAF? Thank you for your time and work.
@@cooldudecs *Yea China has struggled to develope Modern-Advanced Engines and still has to buy Russian engines and replicates older soviet era engines.*
The two variables in these things are pressure and volume, similar to voltage and current (or amperage) in electricity. I'm curious if the flux density of the detonations, or of the space between them is a factor in their size.
I can't remember a single modern airborne missile, arming planes in aircraft carriers, that uses liquid fuel. It's probably a solid fuel RDE, that's a whole different thing.
@@forgotten_world why does that matter that they are only Just using JASSM off carriers. Liquid fuels are more energy dense and can be used in air breathing engine. It looks like extended range and speed is what they are trying to achieve.
@@JohnFrumFromAmerica My comment was about the video, watch it first to understand. Also, turbofan missiles are subsonic or transonic. High speed, high performance missiles uses solid propellant rockets.
@@forgotten_world I know that but it looks like the purpose of this technology is to allow for speed of a solid fuel missile with the range of a turbo fan subsonic missile.
Hi Alex, You should look into the Sunflower Program. It was the development and testing of the first prototype heat seeker. Obviously, it was a highly classified program. If I remember correctly, it ran in the late forties and into the fifties. I think Sunflower was the name of the program but that might have been the name of the device. Anyway, it was mounted in the top of a B25 (I think) and it tracked the sun as they flew around South West United States. I believe at one point the plane crashed and there was a scramble to find it covertly. I'd love to hear the whole story. Thanks for all the excellent videos.
I am very excited to see what the space exploration industry can do with this technology. I'm thinking space-based telescopes, that are stationed in an array, around the outer limits of Pluto's orbit. Think about the group of land-based telescopes that were responsible for the image that we got of black hole M87, and then make a telescope array, the size of Pluto's orbit.
Little history on Pulse Detonation devices. Throughout the 80s, 90s, there were unique contrails seen in the skies. Which made perfect flight paths from Area 51, Nellis AFB, Edwards AFB and Lockheeds old facility in California. The contrails and Sonic booms measured and seen, are only possible when using pulse detonation as a propulsion.
Deflagration made a lot of noise, so detonations means it will do a lot more noise. I don't think it will find many applications on ships and low altitude flights, and I believe it is better to use for a short period due to its instability.
It would be great if you would compare China vs. The United States of America’s industrial and manufacturing capacity. Any war between us and China is going to come down to who can build more ships, tanks, planes, landing craft, etc. Shiny new weapons are nice but unless we have the steel, aluminum, IC chips, and factories to build them they are useless. Germany had lots of cool weapons programs during the Second World War but we just produced far more then they could ever dream of. China will come at us with tens of millions of troops across every island in the pacific. We had better be able to build more aircraft carriers and other ships than they can or we are toast.
Our ability to quickly mobilize is a fraction of China's ability. They have all the related industries that can be quickly switched to military applications - the reason America won the 2nd world war. Our own people did this - I don't blame the Chinese.
China would own the United States in a long term conflict. Because the first thing China will do is take control of Taiwan. Why is that important? 95 percent of our computer chips for weapons, flight computers, shipboard computers for radar guidance and detection, sonar, propulsion, electric power generation come from Taiwan. Think about that. With our supply chain shortage as of now, parts and supply’s are already limited. As were used missiles and lose ships and fighter/bombers due to battle. We would have a very limited ability to replace those things. We are dependent on Taiwan’s chips.
At 15:58, "... Rotation Detonation Engines could help fighters fly further..." --------------------------------- A small point of grammar on numerous instances throughout the video-- "further" refers to an increased degree or extent, and "farther" refers to actual distance. Example: "In effect, an RDE engine further advances efficiency, allowing the fighter to travel farther on the same fuel." * Your narrative remains a model of clarity and logical development.
The V1 flying bomb built and used in WW2 by the Nazi's was powered by a pulse jet engine. It made a very distinct sound as is passed over head, and when the sound stopped, people knew it was about to come down.
Can you imagine a group of Engineers from SpaceX, Blue origin, Boeing building prototype designs of a rapid detonation engine just to see if it's feasible for space exploration. The Geek in me right now is giggling just at the thought of it.. thank you Alex this is like getting a Christmas present at the beginning of August, really helps take your mind off the heat. Keep posting and we will keep watching
Another outstanding video, my friend! Greatly enjoyed your breakdown of this new combustion concept. I see a very crude and oversimplified illustration within the Wankel rotary engine. Again, thank you for another enjoyable video. Have a fantastic week, my friend. 🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸
Yes to video of chi-com hypersonic attack missles, and their threat to USN vessels and other topics, and what we are developing to defend against them. Bug time!
I am fascinated by this video. 😃 I want to see this followed as often as new information arises. I enjoy all of the videos you present; they are very scientifically as well as intellectually satisfying. I also would like to see any new information concerning the Dark Star & The 3TRB. Whether the rumors are true or false about anti-gravity: the whole concept has fascinated me since my growing up in the sixties and spending my days in the library pouring over scientific periodicals and books. Even just knowing that these things are theoretically possible gets me excited about seeing it through from theoretically possible to Scientific Fact 😃 Thanks!
It looks very much like a ram jet . With enough testing there’s no telling how fast they can get them to go , it’s a matter of once it’s running getting the fuel and air in fast enough!
Looking at the ideal model of a PDE, from time index 4:02 if the RDE is based on the PDE, in theory you could extend the operational ceiling by introducing an oxidizer to allow a missile or a jet fighter to fly higher in the atmosphere, where there is far less oxygen available for combustion. The engine's computer could automatically increase the flow rate of the oxidizer to maintain thrust, to compensate for the drop in external air pressure (and the consequent drop in oxygen's partial pressure) as the missile or jet fighter climbs to higher altitudes. Then as the missile or jet fighter drops back down, the engine's computer automatically decreases the flow rate of the oxidizer. Another application for such a hybrid jet/rocket engine may be to build an automated vehicle to Scientifically explore the region between the Mesosphere and Low Earth Orbit (LEO).
10/m sec vs 2000/m sec? That's huge. If you could put that to use in an IC engine, we could get huge range improvements that could essentially kill electrification of vehicles.
Yes would enjoy a video on the range of missiles from China anti ship stuff. Thanks for the content and keeping us lay people in the loop of qhats going on behind the scenes. We spend a lot of money so it's nice to see where some of it is going
Nicely done. Thanks. Former USAF officer here. Trade offs. The issue is one of materials science. Rotational detonation engines (RDE) provide much greater pressures and thrust but you have to have the alloys strong enough to take the high temperatures and pressures without failing. Those types of alloys increase cost and very likely weight. Have served in the Tactical Air Command, I am fighter biased, but RDE technology may be better suited to 1) missiles that make one trip to their target; and 2) naval vessels that have less concern about weight of the propulsion systems. Air superiority depends on mission readiness, availability, and turnaround time. The more sophisticated the jet, the longer and more complex the maintenance. That increases turnaround time even if you have the tech, parts, and highly educated human capital to sustain such intense maintenance. That is difficult in a secure environment far from threats, but much harder closer to combat. As noted, these jets would be ungodly expensive as would be parts and maintenance. That leads to fewer jets and fewer training hours for the pilots-availability and readiness issues. I am not saying this is not a potentially revolutionary technology, nor am I saying that we should not deploy it where it is better suited. What I am saying is that we have to think about full lifecycle technical trade offs, costs, logistics, maintenance, availability, and readiness to best achieve our strategic and tactical objectives.
Shocks. No discussion about embedded shocks.
I used to know quite a few DARPA people (not all were engineers) and there is a common saying they have. 'About 50% of the things that are said to be impossible really are'.
That means 50% aren’t impossible and thus buildable. I am a glass half full (50%) kind of person.
@@radiofreealbemuth8540 that was the joke
Icarus didn't have the Federal Reserve! I'm certainly no engineer but I'd say 50% of things said to be impossible aren't financially viable 75% of the time lol.
I used to know a bunch also......but for only three years. I got attacked by crickets in Canada while listening in on some bears. Microwave pinball can really get the ears ringing.
Impossible until possible, unless the laws of physics really say it can't be done.
I'm not going to lie. It's a good time to be an aerospace student. Things are getting shaken up in a really cool way.
The proper, simple, explanation for why detonation engines might be worthwhile to pursue, is this:
All thermodynamic engines get their energy from fuel being burned with oxygen. That's the start, and it's the same for all engines. There is not 'more' energy available for some engines than others. It's only the chemical energy in the fuel, a fixed amount. Same for all. What is not same for all, is how much of that energy, the engine is able to convert into work. This is why we have the concept of thermodynamic efficiency. (With rocket engines and jet engines we also have propulsive efficiency, but forget about that, because this does not concern that.)
Now it happens that all thermodynamic engines extract their work from the ' *_Expansion_* ' phase of their working gas, which typically - and particularly in this case -, is the same as the combustion gases. The greater the expansion, the more work = useful energy, is extracted.
Now we come to the first point: You can have more expansion if you first *_compress more_* . This is why we have Diesel engines. It's why the most advanced jet engines have pushed to 80:1. It's why SpaceX is pushing for +300 bar in their Raptor rocket engine.
But, here's a crux: As the fuel burns, the combustion gas expands (in *jet* *engines* and *rockets* , in piston engines you of course get the combustion *_before_* expansion), because the expansion moves faster than the burn reaction. So you don't get to suck all energy from the max, theoretical, possible expansion. What if you could have the reaction (fuel burn) take place before the gas expands? This should result in better fuel efficiency. And it will be achieved if the reaction (fuel burn) is faster than the gas' expansion. And that is what we call *_detonation_* . The full burn first, then the expansion, instead of expansion during the burn.
@Vermilliontea,
Very well explained. Thanks, your post was helpful.
Great explanation!! Thanks!!
Didn't think this video could be better. Your explanation supports why Japan, Australia and anyone frankly able to produce this technology would. It's applications are beyond military and aerospace.
How come the fuel can both deflagrate and detonate? What’s the difference between these two modes?
@@user-ee1fn4vt8b During Deflagration (gunpowder, smokeless powder, petrol, etc.) the burning front moves through the fuel/air mix below the speed of sound in the combusting material or the working fluid. During detonation (TNT, RDX HE generally), the burning front moves through the material at greater than the speed of sound in that material.
I actually wouldn't mind you going over china's anti ship weapon along with their strength and weakness of them
I agree I wanna know how good there weapons really are
Oh yeah the DONGFENG 21 and 26!!!
The issue with that is that Russia and China are more secretive about its tech than the US is. (Especially China.)
Yeah that would be pretty cool
i really hope President Biden and family doesn't give this tech to the Chinese.
You may not be a scientist but you explain pulse detonation and the difference between a internal combustion engine and this process better than most science articles I've read about it. I'm a science and technology geek and your information is always spot on and accurate something I applaud you for. You take the time to get the details right. Your humility leads to higher accuracy.
Agreed, and I’ve done several operations in both fields.
It's perfectly normal as scientists are generally expected to do scienscy stuff instead of being educators. Sometimes a person can be both, like Anton Petrov or Stephen Hawking, but it is not a must. Division of labor and specialization.
Absolutely love technical advancement videos like this! Super, super interesting! 🤙
Alex, thanks for the excellence of your English, a rarity on UA-cam these days. Needless to say, your content is superb.
This is the coolest military news channel. I love all the videos.
I worked with Dr. Fred Schauer on the worlds first self-aspirating PDE in the early 2000's, which is later developed to what you see at 7 minutes. You can basically eliminate the pumping losses of a compressor section, and get MUCH higher exhaust velocities. We built it out of a cylinder head on a shoestring budget. I thought this tech never panned out, but this concept is great! The donwside...this thing sounded like a jackhammer, but as loud as artillery. An RDE might also make a decent tip jet on a helicopter or prop.
Was that the one made from off the shelf GM parts?
@@oleran4569 Yeah- Oldsmobile quad-4 cylinder head fed the detonation tubes. A motorcycle engine was needed to run a compressor to force air through that restriction though.
It's actually really interesting how the energy is extracted makes a big difference. We have detonation in diesel engines but it's been a struggle to get it to work in gas. I don't know if the entire charge detonates in diesel engines even. It might be interesting if it could be made cheap enough eventually to offer an option for vehicles. It could make the transition to lower carbon power sources easier.
Cool video. I would like to hear the one about China as well. Yours is the only one of these style channels that I feel gives quality information and isn't tacky. Keep up the good work.
Actually, none of the charge detonates in diesel engines. It burns. You never have a supersonic combustion front or shock wave inside a diesel engine (or at least if you do, you're having a really bad day).
That's also true in gas engines - the goal to get compression ignition gas engines to work is to get them to compressively ignite in a controlled way without generating a detonation wave, because detonation waves inside piston engines tend to break things.
As stated above, there is no actually detonation going on in diesel engines. The flame spreads slower than the speed of sound in the fluid. It merely deflagrates.
My understanding is that gas engines have a singular flame front spreading out from the spark plug, whereas diesels have many smaller flame fronts detonating throughout the combustion chambers.
@@taylorc2542 It's a nitpicky issue of terminology, but an important distinction. Often, when the fuel-air mix is ignited in an internal combustion engine, people refer to it as a detonation, because it's a very brief, loud, powerful burn. But technically, it's a "burn", and not a detonation.
Imagine pouring some fuel on your BBQ grill. you light it, it goes WOOSH! with a fire ball, and your eyebrows are ruined. That's a burn, or as the video is called it "deflagration". If it were a "detonation" it would go BANG instead, and instead of looking like a miniature napalm experiment, your bbq would look like a miniature fuel air explosion, and there'd be pieces of your grill falling 3 blocks away. possibly pieces of you too :P
Anyway, internal combustion engines don't detonate, even if it is fast, it's not supersonic. And yeah, a lot of car people might call it a detonation, but not technically the right term. If it were a true detonation, then the piston would move down at supersonic speed. And nothing about the block, crank, or piston is really designed to handle that.
The way something burns makes all the difference.
There's as much energy in a ham sandwhich as there is in a stick of TNT, or a similar weight of C4. The differences are all in how rapidly they burn.
Heard about it 5 years ago. From what I remember they had huge problem with two of those rotating shockwaves (there always has to be at least 2) bumping into each other causing whole thing to be unusable
I mean it’s been a few years so I guess they ironed out the problems
DARPA announced they're starting an 18 month design phase with various contractors. That will be followed by an 18 month full scale test phase. So yea...I think they ironed that stuff out :)
edit:words
@@Future-Preps35 hold on I'll just grab my hot glue gun...
Any missile technology is good right now.
That missile truck the USAF wants to build will seem viable. Having one plane dropping 60 plus cruise missiles with increased range make it more viable.
Of course it will be paired with other aircraft to locate targets. Forgot the name of the units but the Wild Weasels was one.
@@Future-Preps35 WOW! They should've just asked You instead of wasting years of Their lives on the research!
You don't get the concept. It works like a gas turbine but instead of combustion there's detonation
Definitely do a video on China’s anti-ship weaponry and their “1,000 mile radius”. People make them sound invincible, and I’d love to see your breakdown of their strengths and weaknesses.
China's military asset are hilariously overhyped.🙈🙈
Thanks for digging in to this!
Your excellent channel definitely gets a score of five Ian's out of five for weaponry youtube channels. (Five little pictures of Ian McCollum giving a thumbs up) Subbed and chit.
I got excited when I saw the notification (for which I had been waiting) and what the topic was. Awesome video. At least 3 times I went to click the thumbs up and forgot I already had.
Great video, as always, Alex! Have you thought about doing a video devoted to the LRASM system? The more I learn about them, the more sci-fi-is-now they seem to be. Pack 'hunting' anti-chinese ship weapons. Their programming behavior is very, very interesting and I think would make a great video!
I'd love to see the LRASM use a rotation detonation engine that's in the video instead of the turbo fan engine 😀
You will, under some name or another, if the RDE proves workable. @@danielsnook7362
Especially when combined with Rapid Dragon launch systems.
I read of a future scenario where the f35/22 control 10s of drones in a forward position while they are in the rear. Couple that with drone refueling and the navy and fighters will be somewhere over the horizon in a battle. Great analysis!
Think about it, this tech has its roots all the way back in the 1930's with the German V-1 Buzz Bomb.
Well, it short of does, same as a calculator is a precursor to a computer, but the difference is immense
Very good overview of RDE technology. I learnt quite a lot from it, thank you.
Great video! I have never seen anything about this technology. Awesome!
Rotation Detonation Engine Engines are so cool!!! 👍
I thought that “afterburners” went out with turbo jets.Turbofans, if so equipped, have “augmenters”, instead of afterburners.This is an important distinction because in addition to what goes through the combustor, augmentation uses clean unburned air bypassed AROUND the combustion chamber. This cools the combustion chamber allowing it to operate at higher pressure ratios AND provides fresh air to the augmenter. All modern fighters use augmented turbofans these days.
Love the updated intro music!
Great content, thank you so much for this, it is real news on the future front.
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Another outstanding and informative video. Thanks for all your hard work putting these together. 👍
Thanks Alex that was very well done keep up the good work brother we need someone who brings things the way they are realistically
Love the presentation, I understand how this would work in missiles and aircraft, but I'm not how this would work in ships. I understand that the engine produces thrust, I'm not sure how it would produce torque however.
Do you need to produce torque? You could use thrust throttling and vectoring (like coast guard jet boats) to steer, rotate in place, even move sideways, power brake, go in reverse. Don't even need a rudder.
The same way a gas turbine makes torque. With a reduction gear.
Think of it like a rotary engine in a Mazda
Many naval ships already use gas turbines (like in a helicopter). The rotating detonation would replace the combustion chamber of the turbine engine. If the technology works as theorized, all gas turbines would eventually be replaced with versions that detonate fuel instead of deflagrating it. (BTW, the turbine connects to an electric generator or gear box.)
less cocaine before recording
We used to call RDE "ultra compression" and knew that it was much more efficient than a traditional design, but it isn't exactly zero maintenance. Parts wear out so quickly that it makes for a disposable engine core with all of the stress fractured components.
Probably why missiles were the first application mentioned. Don't have to do any maintenance.
I had this idea years ago also and its perfect for long range stealth aircraft because of the reduced heat signature of the thrust.. and commercial airliners with vertical takeoff and landing..
Sure, I bet you did. I had the idea of both radio and television in a past life. Right after I gave Edison my idea for the light bulb.
Frreeman Dyson used a simular idea or technology to use a Nuclear Powerplant to power infrared waves on to a metal tungsten rod that reacted to infrared waves to create a non 02 detonation and create a detonation pulse that would in theory provide a infrared magetic pulse engine. He worked for General Atomics at the time and this was supposed to be used for the Orion Space Craft slated to go to Mars. I do not know if we ever went. I can only dream we did as an explorer. This is like sailing a ship to a new far distant land.
How loud are these engines compared to conventional jets today? Doesn't seem like you'd have a lot of means to do baffling. Not a big deal for missiles or even planes if they're going Mach 5.
But for ships, does the engine stay above the water? Or is it detonating in the ocean? Water carries sound very far and fast - and if there's a stronger pressure wave (ie: louder), you could both increase detection range and probably kill or disorient a lot of fish and whales and other marine life (already a problem today).
I haven't looked into it, but just curious.
AFAIK, it breathes air and will turn a turbine shaft. I believe the intent is to just replace the current engines with something more efficient. A detonation wave travels at supersonic speeds, so it would make sense that the engine's fundamental frequency would be well above ultrasonic. If so, it should be easy to create isolation mounts.
It would just be the engine to turn a shaft, not a jet into the water
It's a very good question, I would imagine such an engine would be LOUD and dangerous. Metal and water and air will as you know propagate a wave, generally the denser the medium the faster the wave can travel, and being supersonic I can't imagine that would or could be used in water, it would be like a weapon itself !
@@psycronizer How could the engine be used in water? It requires air (or gaseous oxygen) to operate. Yes, it creates an exhaust gas stream, but that isn't fundamentally different from current turbine engines.
So if you were committed to using a high-speed exhaust gas as a weapon, you could do it now.
@@psycronizer well, it doesnt matter that you cant imagine it. the guys at DARPA did imagine it and are making it happen so in a few years when this is common tech, i wonder if you will remember saying this wont work
Hey great vid ! Just to add in more technical detail the reason detonation creates more thrust from the same amount of fuel or 'specific thrust' is due to the increase in thermodynamic efficiency as seen in comparing a Fickett-Jacobs and Brayton cycle P-v digram. This is due to detonation wave moving at sonic velocities creating a shock and pressurising the reactants without the need for a piston/compressor blades. this is why its so called 'pressure gain combustion' although when looking at the cycle as a whole no thermodynic laws are being broken as the name suggests.
Also i think some italian guys have already flown one on a model rocket as well as mbda looking into this concept recently, i alos know of a paper detailing the incoperation and running in of a RDE combustor in a gas turbine. Can source if intrested.
I think these engines were tried by Heinkel Hirth at the same time as von Ohain Jet engine was being developed in the 1930s. They were referred to as 'constant volume' jet engines instead of the 'constant pressure' types we know. A compressor filled several combustion chambers in turn using poppet valves. Sparking plugs ignited the mixture and the exhaust propelled the aircraft. They operate at much higher pressure and temperature ratios. Mentioned in Anthony Kays "German Jet engines and gas turbines"
No, they were not. Entirely different setup.
They were pulsejets, as described at the beginning of the video, and they operate at absolutely miserable pressure and temperature ratios, producing absolutely miserable thrust and efficiency.
@@wagnerrp Constant Volume Jet engines are not the same as pulse jets. Constant volume engines used compressors and poppet valves to admit air to a number of combustion chambers, close the valves and ignite. Another poppet valve would then open to release the gas over the turbine. They are theoretically much more efficient than standard constant pressure jet engines.
@@williamzk9083 A pulsejet is a constant volume jet engine. You're just describing a different type of jet engine that honestly sounds like an nightmare for maintenance and cooling. Pound for pound, reciprocating engines are shit for reliability, and the lack of opportunity for film cooling in the combustor means your materials are going to have to have to carry the full thermal load of combustion directly, while simultaneously receiving tremendous cyclic loads.
Anyone else see DARPA and get excited?
Rotation Detonation Engines work on basic thermodynamics: the higher the starting burn, the more efficient the engine ought to be.
What stops the highest temperatures: materials. Diesels have to use inter-coolers after the turbo-boost just to save the engine.
From a purely thermodynamic point of view, the ideal engine wouldn't have one. (Highest efficiency would degrade unit specific output -- less HP.)
RDE hopes to fuse the episodic burn seen in ICE engines -- where the burn temperature is quite high compared to the containment metals --
with the flow through seen in open Brayton cycle engines. ( gas turbines )
If RDE geometry can be solved, the Big Change would first show up in the use of MUCH cheaper metals for turbines.
RDE tech would not change the nature of after-burners. They'd still be fuel pigs.
For ultra-speed applications, we've already hit the wall in terms of materials.
RDE -- it is hoped -- would allow super exotic performance when exotic materials were employed.
It'd be like a rocket motor that does not need regenerative cooling. (The latter chills expansion gases that you really wish to keep super hot.)
Such wasted thrust is most evident in the classic NASA footage of the Saturn V at lift off.
A skirt of un-burnt propellant shoots down -- hiding the flame -- until about 2 meters below the nozzles. Then the gas bursts blindingly white hot.
Of course, the whole idea of using naval air against Red China is a joke. As seen in 1945, carriers sail close only to deliver the coup de grace.
Red China will be defeated by radio announcement. Once the USN broadcasts that merchants sailing to Red China are suicidal -- no-one will do so.
There will be no repetition of the Battle of the Atlantic. (1939-1945) Red China's war industries will collapse faster than Putin's.
The temp issue is solved with the use of inconel 625 nickel allow metal. Spacex and other rocket companies have improved their engines with the use of the metal because it has extreme upper temp limits.
Calm down Tom Clancy.
IF they have really solved the technical ceramics crack propagation, this would improve all heat engines a lot. Hundreds of deg higher operating temperatures. Somewhere I've read that the they are testing the first aircraft engines with ceramic blades. This ceramic has nothing in common with the household ceramic.
@@panan7777 No one really thought that we would be making blades of recycled coffee mugs. 😀
We must notify the Navy that much of their efforts are unneeded. I'm sure they'll be greatly relieved.
There are these 2 things to extend an airplane's range we've been using for years - drop tanks and air-to-air refueling.
I'm curious to see if the RDE concept is what would power a potential hypersonic fighter, which I believe you discussed in another video or perhaps on your website. The use of RDE in manned fighters and drones would indeed go beyond next gen.
@@brobasticbroham446 I agree with your premise, that said as technology increases and stealth capabilities are made more compatible i.e. ceramics to increased speed. The need for speed will be incorporated, for it too offers increased benefit. I purposefully used ceramic because I've seen that there's a current push for more reliable maintenance wise and higher temperature resistance radar absorbent material.
Hyper jet fighters would be ultra expensive to produce and maintain, having a pretty short service life.
@@hansybarra Technology is ever increasing and you bring up a valid point. Currently it's expensive.
Check out Rotary detonation engines. This is hypersonic flights future.
Adaptive cycle engines are currently being deployed in F-35'S.
Don't let Evil china steal this tech!! They will make copies of it and make them really cheap to buy , even north korea can afford it.
hypersonic fightesr are useless. Why would you want to go that fast when it does nothing to defend against modern missiles?
For the curious, Scott Manley has a video on RDE. Sandbox: how about do one on what is known about pulse detonation engines?
As always informative and well explained!
Scott Manley has a video on how rotational detonations engines work, if you're interested.
Def would like to see how to penetrate the 1000 mile bubble zone. Thanks, Alex :)
Great video. This tech is closer to working its good to get a better idea of just how it works.
Hey, could you do a video or series on the current and near future state of anti air weapons?
Which MANPADS do exist, what will replace the Stinger? What is the state of lasers? Which longer range options for ships and on land do exist? What do fighters have to shoot down other planes? What is currently in service or in development, either by government contract or from manufacturers?
This would work well as a mini series either by range/type of defense or country of use.
My wife tells me I need a man pad sometimes 🤣
How long does it typically take DARPA to develop & refine a concept to where it's out in the field for the military & is operationally available?
I think DARPA actually just identifies where potential breakthroughs are and provides financial incentives for other groups to yield results. DARPA has many projects of many different fields of expertise, so the projects don't overlap much in terms of the facilities or people actually doing the research. They hosted competitions for self-driving vehicles years ago, but the implementation of such technology in both civilian and defense applications is gradual with many iterations.
That’s the military’s job, DARPA identifies opportunities for contracts.
Great work as usual... definitely interested in seeing more on China's growing capability to strong-arm its neighbors and what can be done to help those neighbors maintain their sovereignty and counter it.
Yea we really need to stop these barbaric criminals CeCePee. They are so power hungry and want to dominate everyone. Without any regard for human rights or human lifes for that matter. We need every advantage we can get in order to hold them accountable. Otherwise they will do what they want and thats not good since they are only intersted in evil things.
With its top 6 chip manufacturers CEO's being exposed as fraudsters and their chips being fake. I doubt the country can do anything now. 50% of the country mortgage payers ain't even paying anymore and since the housing industry isn't getting more money. That 30% of China GDP is gone. The country is gone in a few years.
Where is all this china this ,china that info coming from. What are our intelligence agencies doing to support this .
Damn it now China will never surpass the us
One good 'guess' would be sufficient for immediate, negotiated implementation. China then couldn't touch Taiwan, et al. results for nations in the Pacific currently vulnerable to China's recent, open threats.
Your videos are the best. Period.
Thanks for a particularly interesting video. I guess the strategic advances yielded by such an engine development would be relatively short-lived, but that is the nature of all bleeding edge technology in weapons design isn't it?
China will be busy trying to hack DARPA's networks immediately.
I'd suggest checking out Perun's recent video about defense procurement. The supercomputer resources that have no doubt been thrown at this problem for decades could be daunting for many nationsto match. And making the best use of the tech requires a military industrial complex that is difficult to match
Depends on how long the IT security people can manage to keep the Chinese and Russians out
@5:04 Neither piston engines nor jet engines have "explosions" happening in them, the fuel in both of them burns.
When explosions happen in piston engines it's called detonation and it quickly causes damage to the engine. Jet engines also burn their fuel in a controlled manner. I'd guess any sort of "explosion" in a jet would quickly damage both the combustors and the turbine blades.
"Subsonic explosions"?!? Check your facts.
I can verify no explosions in jet engines. I worked on and operated GE LM2500 gas turbines engines in the US Navy for 20 year for ship board operations. In starting, the igniters are energized. The fuel is pumped into the combustors. Think of holding a lighter in front of a can of hairspray. Then depressing the little release nozzle on top of the can. That’s a crude way of describing light off. In the meantime a starter motor is turning the compressor of the turbine to produce air for combustion during the start sequence. Once the engine picks up to self sustaining speed the starter motor kicks out. Once the engine is up and running, the more fuel you send to the combustors, the more combustion which increases the exhaust gases to the power turbine. Our ship board engines didn’t have afterburners. Our power turbines were coupled to a reduction gear set thru a high speed flexible coupling and clutch. After passing thru the power turbine the exhaust gases are vented to the atmosphere thru the exhausts. No explosions for normal operation. Now if you do a hot start by going thru start up improperly then yeah you can get a mini explosion which can damage the engine. So maybe that explains the start and operation of a jet engine in a nut shell for those who don’t work on or operate jet engines without getting too technical. Just gives a basic idea. The explosion theory is wack. Because anything sucked into the intake damages compressor blades which at high speed can sheer off and migrate down stream or sling out thru the engine casing. If their is damage to the combustors, it is usually sent down stream to the spinning power turbine which takes out power turbine blades. Either of which is catastrophic to the engine. So no, an explosion is very undesirable.
I think the airline industry would benefit from this technology by save a lot of money on fuel consumption thus lowering the cost of passenger tickets.
Yea I'm curious how well the technology scales down. Is it still as efficient if you're going subsonic at normal speeds?
Yes, I want to know about the areal denial issue!!!
Due to a fuel shortage Germany is considering coal fired missiles.
Back to some things considered during World War II? I'm thinking of things like the Lippisch P.13B.
Thank you again for your video, , my friend.
I recently read an article which, if memory serves, dealt with Toyota and its pursuit and development of a rotational detonation engine which could find application in the company’s automotive industry.
Thank you again and have a great week.
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imagine it reaching the private sector as well, electric cars with little generators operating on the principle. the fuel savings per watt and lack of costs related to maintenance and upkeep of combustion engines.... as well as being used by commercial companies who charge customers for electricity... the savings are far more impressive... reducing costs and such... i wonder what the emissions are like for them, i would assume much better and you would never need a catalytic converter ever again.
I don't think there exists a tech today that allows for practical, on demand energy extraction from a detonation...
Nicely done video. Excellent explanation and pace. Thanks!
Is there a question about the theory of decentralizing existing platforms and is whether it is possible to create a decentralized ground-based AEGIS system for the US ARMY and another air transported for the USAF? Thank you for your time and work.
I thought they already had a version of aegis ready for the army.
Don't let Evil china steal this tech!! They will make copies of it and make them really cheap to buy , even north korea can afford it.
WABOC.
Its awesome how fast this engine is progressing. Its now 2023 and i just seen the video of a long time Test fire of this engine and it looks awesome.
China gonna copy this too
I’m sure someone high up already sold them the blueprints
They won't have to. We'll give it to them.
Na this is an engine… It’s very difficult to copy like a fuselage or some circuit try . Engines are usually made with equipment we only sell here …
@@cooldudecs *Yea China has struggled to develope Modern-Advanced Engines and still has to buy Russian engines and replicates older soviet era engines.*
They don't need to copy. We'll do that and send them one.
Pulse detonation, in conjunction with an aerospike nozzle would enable maximum efficiency at all altitudes, as well. Niiiice!
The two variables in these things are pressure and volume, similar to voltage and current (or amperage) in electricity. I'm curious if the flux density of the detonations, or of the space between them is a factor in their size.
Wow, good job, Sandboxx!
I can't remember a single modern airborne missile, arming planes in aircraft carriers, that uses liquid fuel. It's probably a solid fuel RDE, that's a whole different thing.
Jassm uses liquid fuel
@@JohnFrumFromAmerica Not operated from aircraft carriers until now, but the SLAM-ER uses jet fuel - not a common weapon there, though.
@@forgotten_world why does that matter that they are only Just using JASSM off carriers. Liquid fuels are more energy dense and can be used in air breathing engine. It looks like extended range and speed is what they are trying to achieve.
@@JohnFrumFromAmerica My comment was about the video, watch it first to understand. Also, turbofan missiles are subsonic or transonic. High speed, high performance missiles uses solid propellant rockets.
@@forgotten_world I know that but it looks like the purpose of this technology is to allow for speed of a solid fuel missile with the range of a turbo fan subsonic missile.
Hi Alex,
You should look into the Sunflower Program. It was the development and testing of the first prototype heat seeker. Obviously, it was a highly classified program. If I remember correctly, it ran in the late forties and into the fifties. I think Sunflower was the name of the program but that might have been the name of the device. Anyway, it was mounted in the top of a B25 (I think) and it tracked the sun as they flew around South West United States. I believe at one point the plane crashed and there was a scramble to find it covertly. I'd love to hear the whole story.
Thanks for all the excellent videos.
I am very excited to see what the space exploration industry can do with this technology. I'm thinking space-based telescopes, that are stationed in an array, around the outer limits of Pluto's orbit. Think about the group of land-based telescopes that were responsible for the image that we got of black hole M87, and then make a telescope array, the size of Pluto's orbit.
I just got to say in many ways you just have to love DARPA.
Little history on Pulse Detonation devices. Throughout the 80s, 90s, there were unique contrails seen in the skies. Which made perfect flight paths from Area 51, Nellis AFB, Edwards AFB and Lockheeds old facility in California. The contrails and Sonic booms measured and seen, are only possible when using pulse detonation as a propulsion.
the contrails look like doughnuts
Best defense channel on UA-cam, could you cover Red Chinese anti-ship weapons?
Deflagration made a lot of noise, so detonations means it will do a lot more noise. I don't think it will find many applications on ships and low altitude flights, and I believe it is better to use for a short period due to its instability.
Air to Air Missiles would be an interesting application for this propulsion.
It would be great if you would compare China vs. The United States of America’s industrial and manufacturing capacity. Any war between us and China is going to come down to who can build more ships, tanks, planes, landing craft, etc.
Shiny new weapons are nice but unless we have the steel, aluminum, IC chips, and factories to build them they are useless. Germany had lots of cool weapons programs during the Second World War but we just produced far more then they could ever dream of. China will come at us with tens of millions of troops across every island in the pacific. We had better be able to build more aircraft carriers and other ships than they can or we are toast.
Our ability to quickly mobilize is a fraction of China's ability. They have all the related industries that can be quickly switched to military applications - the reason America won the 2nd world war. Our own people did this - I don't blame the Chinese.
China would own the United States in a long term conflict. Because the first thing China will do is take control of Taiwan. Why is that important? 95 percent of our computer chips for weapons, flight computers, shipboard computers for radar guidance and detection, sonar, propulsion, electric power generation come from Taiwan. Think about that. With our supply chain shortage as of now, parts and supply’s are already limited. As were used missiles and lose ships and fighter/bombers due to battle. We would have a very limited ability to replace those things. We are dependent on Taiwan’s chips.
So f*cking awesome Darpa. 🔥🔥🔥🔥🔥
Wow this rotation combustion technology sounds very promising the future, well presented, even I could understand this concept.
Great video. Excellent narration.
This would be huge for the future of tanks as well
Great video, Alex. I've been saving it for a few weeks, but it was worth the wait!
That’s pretty mind blowing
Very exciting new technology wow!
Fun fact: deflagration is what a low explosive does. Detonation is what a high explosive does.
At 15:58, "... Rotation Detonation Engines could help fighters fly further..."
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A small point of grammar on numerous instances throughout the video-- "further" refers to an increased degree or extent, and "farther" refers to actual distance.
Example:
"In effect, an RDE engine further advances efficiency, allowing the fighter to travel farther on the same fuel."
* Your narrative remains a model of clarity and logical development.
Great Coverage as Always Alex!
The V1 flying bomb built and used in WW2 by the Nazi's was powered by a pulse jet engine. It made a very distinct sound as is passed over head, and when the sound stopped, people knew it was about to come down.
Can you imagine a group of Engineers from SpaceX, Blue origin, Boeing building prototype designs of a rapid detonation engine just to see if it's feasible for space exploration. The Geek in me right now is giggling just at the thought of it.. thank you Alex this is like getting a Christmas present at the beginning of August, really helps take your mind off the heat. Keep posting and we will keep watching
I ONCE DESIGNED A PISTON TURBINE ENGINE WITH DEFLAGATION EXHAUST THRUSTING. THAT WAS LIKE 15 YEARS AGO AND WORKS ON A SIMILAR PRINCIPLE.
Excellent and intriguing.. thank you.
A video on DRONES & SUBMARINES..??
An RDE that has fuel with an oxidiser in a separate tank to go from air to space in one craft. Give it thrusters and there you go.
Deflagration is subsonic. Detonation is Super sonic at more then 30 times the pressure. Using roughly the same amount of fuel.
Anyone else feel like this video left us hanging? Where is it at in development? What are the challenges RDE development?
Excellent analysis
Now that is a game changer for sure.
Another outstanding video, my friend! Greatly enjoyed your breakdown of this new combustion concept.
I see a very crude and oversimplified illustration within the Wankel rotary engine.
Again, thank you for another enjoyable video.
Have a fantastic week, my friend. 🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸🦅🇺🇸
at 6:00 minutes I Got It Precisely , Thank You for taking the time to explain it perfectly..........
Yes to video of chi-com hypersonic attack missles, and their threat to USN vessels and other topics, and what we are developing to defend against them. Bug time!
I am fascinated by this video. 😃 I want to see this followed as often as new information arises. I enjoy all of the videos you present; they are very scientifically as well as intellectually satisfying. I also would like to see any new information concerning the Dark Star & The 3TRB. Whether the rumors are true or false about anti-gravity: the whole concept has fascinated me since my growing up in the sixties and spending my days in the library pouring over scientific periodicals and books. Even just knowing that these things are theoretically possible gets me excited about seeing it through from theoretically possible to Scientific Fact 😃 Thanks!
It looks very much like a ram jet . With enough testing there’s no telling how fast they can get them to go , it’s a matter of once it’s running getting the fuel and air in fast enough!
I studied pulse-jet engines in PreFlight School at Pensacola in 1961. Their example was the German "Buzz-Bomb" of WW2.
Looking at the ideal model of a PDE, from time index 4:02 if the RDE is based on the PDE, in theory you could extend the operational ceiling by introducing an oxidizer to allow a missile or a jet fighter to fly higher in the atmosphere, where there is far less oxygen available for combustion.
The engine's computer could automatically increase the flow rate of the oxidizer to maintain thrust, to compensate for the drop in external air pressure (and the consequent drop in oxygen's partial pressure) as the missile or jet fighter climbs to higher altitudes. Then as the missile or jet fighter drops back down, the engine's computer automatically decreases the flow rate of the oxidizer.
Another application for such a hybrid jet/rocket engine may be to build an automated vehicle to Scientifically explore the region between the Mesosphere and Low Earth Orbit (LEO).
About time. I wrote about this TIMING ISSUE to a university in Washington State. Looks like they listened.
Nice to think this info is on the net, so our potential enemys aren't too far behind us. Old fashioned to want a strategic edge I know...
10/m sec vs 2000/m sec? That's huge. If you could put that to use in an IC engine, we could get huge range improvements that could essentially kill electrification of vehicles.
not really, the noise would be unbearable, and such engines wouldn't do very well in any kind of land vehicle that has to change speeds alot.
@@hughmungus2760 Yeah well, details. I'm just ignoring that part. 😅
Pulse detonation engine shrunk down into a missile would be game changing!
Nice explanation, Alex.
Yes would enjoy a video on the range of missiles from China anti ship stuff. Thanks for the content and keeping us lay people in the loop of qhats going on behind the scenes. We spend a lot of money so it's nice to see where some of it is going