Ok, here's an idea to probe Rotating Detonation Engine flow fields!

In a cylindrical thin channel, ignite a flame at its center. The flame grows radially until it barely reaches the end wall. In the annulus separating the flame and the wall, there is a layer of non-reacted compressed gas. Then ignite a detonation in that layer. The spinning detonation has all the required ingredients to be relevant to RDE’s, being weakly confined by combustion products. The end wall can be made rough, porous etc to extend to more and more realistic scenarios.