Detonation engine is about how the combustion works. It has no relationship with speed. In principle it can work from zero speed all the way up to hypersonic.Does a rotating detonation engine have any advantage over scramjets ? If so what ?
that’s a pulse detonation engine, not RDE. PDE is also a promising power but for now RDE is closer to practical.No, a detonation engine uses a different operating principle than a scramjet. Like the name implies, one uses detonation of fuel, the other uses deflagration of fuel. Detonation engines in principle should be both more efficient and higher performance. But getting them to work reliably is really tricky.
A pulse jet engine, like the one used in the V-1 buzz bomb from WW2, uses a similar operating principle to a detonation engine. But the operating frequency of the engine in a pulse jet, related to the time between each detonation, is low enough that the performance is lower than modern jet engines. Modern detonation engines are supposed to operate at much higher frequency to get to their high performance level and are hard to make in practice. Vibrations can easily destroy the engine. And like a pulse jet a detonation engine is noisy like hell. So this won't be used in civilian transport that is for sure.
Nope. The fire (burning region) ‘runs’ through a circle (drum), it’s not pulsed. There’re also oblique detonation engines, which are also continuous burning but the region is fixed.RDE is also pulsed. It’s just the rotary mechanism controls the pulses rather than depending on a valve.