Oblique wave detonation engine may unlock Mach 17 aircraft

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World first: Oblique wave detonation engine may unlock Mach 17 aircraft

UCF researchers say they've trapped a sustained explosive detonation, fixed in place, for the first time, channeling its enormous power into thrust in a new oblique wave detonation engine that could propel an aircraft up to 17 times the speed of sound, potentially beating the scramjet as a…
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Dumb question here. Would it be any louder than a standard turbine engine burning fuel at the same rate?
 
Wave detonation engine, pulse detonation engines are they the same or different?

No search ups for of a term called wave detonation engine existing other than giving me pulse search results so the only two different detonation engines are pulse and rotating I assume if wave deserves its own category. Starting to see a funny trend here, one country starts the trend of introducing HGVs, scramjets, photonic radars, nuclear engines for deep space travel and than pulse detonation engine projects(assuming if pulse detonation engine is just a wave detonation engine). Than moments later it starts to become a trend for another country. Just a fun thought, but I am looking forward to placing a bet that NGAD will have a PDE option.

EDIT: found some cool sources.

1620837466595.png

https://media.nti.org/pdfs/NTI-Hruby_FINAL.PDF page 17

"Short boost phase: The short-boost-phase claim is somewhat puzzling, because the Sarmat, like the Voevoda, uses liquid fuel.11 Liquid fuels tend to produce longer boost phases than solid fuels.12 It is hard to be definitive about what is behind the shortboost-phase claim, but there is substantial reporting suggesting the new first-stage engine for the Sarmat, the PDU-99,13 is being designed to lower the signature and/ or increase the thrust and boost speed of the Sarmat. Reporting consistently names Energomash as the engine design agency; however, whereas many report the PDU99 is a variant of the engine used on the current Voevoda,14 others claim it is a more advanced pulsed-detonation engine.15 Some reports assert the new engine will hyperaccelerate the Sarmat into orbit, reducing the infrared signature of the launch as well as the time available for earlywarning satellites to detect such a launch.16 Since infrared signature is closely related to engine type, fuel composition, burn time, rocket geometry, chamber parameters, and flight conditions,17 it is possible that a new engine and/or new fuel could cause the boost phase to be harder to detect and characterize. It is widely reported the PDU99 was tested in August 2016, although no detail is given about the engine.18 Later that same month, it was also reported, a full-scale pulse detonation engine was tested by the Russian Advanced Research Foundation19 supported by Energomash. The Advanced Research Foundation engine was said to employ clean fuel and obtain high thermodynamic efficiency while providing lower cost and increasing the payload weight for space missions."

Other sources have suggested that avangard uses a scramjet, than another source states special engine. https://naukatehnika.com/vrashhayushhijsya-detonacionnyj-dvigatel.html

"To date, GE Research has already solved many fundamental problems related to hypersonic transport. For example, the company develops ceramics that can withstand the high temperatures created by a rotating detonation engine because it contains an endless explosion. Such innovations will return commercial travelers to supersonic aircraft by 2025. The U.S. Department of Defense announced earlier this year that hypersonic transportation should be a top priority. The Pentagon is pushing Russia, which has a Vanguard equipped with a special engine, and China is also claiming a powerful program of hypersonic missile research."
 
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A pulse detonation engine is exactly that, pulsed. Push fuel into the chamber, detonate, purge and refill the chamber, repeat.

(A pulse jet like the V-1 is a pulse deflagration engine, the fuel burns rather than detonates)

A rotating detonation engine is effectively a ring of pulse detonation engines without walls between them, each pulse creating the shockwave that triggers the next pulse around the ring. So comparable in some ways to the way a Wankel engine has rotating combustion (deflagration) chambers, the detonation of one chamber setting up the conditions for the next detonation. The advantage is you can create an effectively continuous expansion of exhaust gases (it's going to cycle up and down in pressure/velocity, but it's likely to be closer to continuous than you would get from a single PDE).

The advantage of this thing (assuming I've understood it correctly) is that it's a continuous detonation. Not Bang! but Baaaaaaaaaaang! continuing for as long as you pour fuel into the point of detonation. Rather than a single pulse, or one pulse triggering the next one, this is a continuous detonation at a fixed point in a standing wave. So you have a continuous exhaust pressure/velocity instead of a rhythmically fluctuating one, and no need to purge chambers between detonations etc
 
sferrin said:
Dumb question here. Would it be any louder than a standard turbine engine burning fuel at the same rate?
Click to expand...
The 'burning fuel at the same rate' makes it anything but a dumb question AFAICS. I suspect it will be louder like-for-like simply because of the difference in shockwave speed from deflagration vs detonation, especially as at some point that supersonic detonation shockwave has to slow to subsonic, but it's not a field I'm remotely competent in.
 
Apologies, I have read the phys source version earlier that did not talk about the continuous wave version from same source

"Rotating detonation engines, in which the shockwaves from one detonation are tuned to trigger further detonations within a ring-shaped channel, were thought of as impossible to build right up until researchers at the University of Central Florida (UCF) went ahead and demonstrated a prototype last year in sustained operation. Due for testing in a rocket launch by around 2025, rotating detonation engines should be more efficient than pulse detonation engines simply because the combustion chamber doesn't need to be cleared out between detonations.

Now, another team from UCF, including some of the same researchers that built the rotating detonation engine last year, says it's managed a world-first demonstration of an elusive third type of detonation engine that could out-punch them all, theoretically opening up a pathway to aircraft flying at speeds up to 13,000 mph (21,000 km/h), or 17 times the speed of sound."

This is also why I was confused that there was a 3rd type when they have announced a 1st type with theoretical mach 20 speeds https://topwar.ru/99945-kratko-k-voprosu-o-detonacionyh-dvigatelyah.html and sources telling me the PDU-99 powering a ICBM is the boost stage PDE.

Also for space interplanetary travel. 5:00 auto-translate english
 
I was googling to see if there was anything on Specific Impulse in rocket mode (the Calvin Nguyen paper referenced by Dannydale above suggests 1800s in air-breathing mode), and came across this paper on rotating detonation wave engines, which doesn't talk about what I was looking for, but is still interesting:


It mentions, but doesn't discuss ODWEs AFAICS, but does give theoretical Specific Impulse for airbreathing PDE and RDE engines of 3860s and 3800s (with hydrogen fuel, 1500s for RDE with propane), which are pretty good, but unfortunately the peak is at relatively low Mach conditions (Mach 1-5), which means they may be useful for getting up to scramjet speeds, but outperformed beyond that. OTOH the Nguyen paper seems* to suggest an ODWE based scramjet outperforms other scramjets and an H2-O2 rocket right up to Mach 23

* Lousy choice of line styles in diagram 5
 
DWG said:
A pulse detonation engine is exactly that, pulsed. Push fuel into the chamber, detonate, purge and refill the chamber, repeat.

(A pulse jet like the V-1 is a pulse deflagration engine, the fuel burns rather than detonates)

A rotating detonation engine is effectively a ring of pulse detonation engines without walls between them, each pulse creating the shockwave that triggers the next pulse around the ring. So comparable in some ways to the way a Wankel engine has rotating combustion (deflagration) chambers, the detonation of one chamber setting up the conditions for the next detonation. The advantage is you can create an effectively continuous expansion of exhaust gases (it's going to cycle up and down in pressure/velocity, but it's likely to be closer to continuous than you would get from a single PDE).

The advantage of this thing (assuming I've understood it correctly) is that it's a continuous detonation. Not Bang! but Baaaaaaaaaaang! continuing for as long as you pour fuel into the point of detonation. Rather than a single pulse, or one pulse triggering the next one, this is a continuous detonation at a fixed point in a standing wave. So you have a continuous exhaust pressure/velocity instead of a rhythmically fluctuating one, and no need to purge chambers between detonations etc
Click to expand...
Have any rotating detonation engines been built? Any pointers to literature on them?
 
www.pnas.org

Stabilized detonation for hypersonic propulsion

There is now an intensifying international effort to develop robust propulsion systems for hypersonic and supersonic flight. Such a system would allow flight through our atmosphere at very high speeds and allow efficient entry and exit from planetary atmospheres. The possibility of basing such a...
www.pnas.org www.pnas.org
 

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