Rotating Detonation Engine, the future of aviation propulsion?

[Abheer Parashar]

TL;DR Summary

Is the use of RDEs for aviation propulsion happening anytime sooner or the use of low/high bypass turbofan engines will continue ?

Hello everyone, I am Abheer and I am a high school student. Few days back I saw an article about RDEs (Rotating Detonation Engines). The article said it is the future of aviation propulsion. I want to ask, is it really so that RDEs are future or the low/high bypass turbofan engines will continue to rule the skies till the end of 21st century ?

 

[Benjies]

Hi Abheer- turbofans will not be replaced by RDEs for subsonic propulsion. RDEs are being researched for hypersonics and alternatives to conventional deflagration rocket engines. The gains in specific impulse would have to be a factor of ten or more to make the RDE compete with a commercial turbofan. This is not feasible, and because RDEs are very complex, I would say that will never happen.

RDEs are being investigated at universities, but they are also being investigated in the military. Currently, the most powerful publicly-acknowledged RDE I am aware of is sitting at 22kN of thrust. This is still not quite cutting it for some necessities in hypersonics, such as packaging limitations, or simply thrust required to maintain a glide at high Mach numbers.

Basically, the "normal, lame" commercial turbofans you know on airplanes are actually extremely well-engineered engines with the highest specific impulses known to mankind for chemical propulsion. RDEs offer something to rocketry, but not to the plane you fly to LA.

 

[Abheer Parashar]

Hi Abheer- turbofans will not be replaced by RDEs for subsonic propulsion. RDEs are being researched for hypersonics and alternatives to conventional deflagration rocket engines. The gains in specific impulse would have to be a factor of ten or more to make the RDE compete with a commercial turbofan. This is not feasible, and because RDEs are very complex, I would say that will never happen.

RDEs are being investigated at universities, but they are also being investigated in the military. Currently, the most powerful publicly-acknowledged RDE I am aware of is sitting at 22kN of thrust. This is still not quite cutting it for some necessities in hypersonics, such as packaging limitations, or simply thrust required to maintain a glide at high Mach numbers.

Basically, the "normal, lame" commercial turbofans you know on airplanes are actually extremely well-engineered engines with the highest specific impulses known to mankind for chemical propulsion. RDEs offer something to rocketry, but not to the plane you fly to LA.

What do you think about their use in fighter jet and UAVs

 

[anorlunda]

TL;DR Summary: Is the use of RDEs for aviation propulsion happening anytime sooner or the use of low/high bypass turbofan engines will continue ?

I want to ask, is it really so that RDEs are future or the low/high bypass turbofan engines will continue to rule the skies till the end of 21st century ?

Whenever you read that something is being developed, or investigated, or researched, it means that the future is uncertain. It may be used in the future if tests are successful, or it may be dropped if tests fail or if major disadvantages are found. There are many more failures than successes.

 

[boneh3ad]

Well that's not really accurate. Diesel engines are still "being researched" and yet have been in practice use for over a century.

 

[Nugatory]

Well that's not really accurate. Diesel engines are still "being researched" and yet have been in practice use for over a century.

We're drifting off topic here, but there is a distinction between "being researched" for economic viability and "being researched" for incremental improvements to something already known to be economically viable.