A Kinematic Study of Individual Rotating Detonation Engine Waves Using K-means Algorithm

The current research is concerned with studying the instantaneous properties of the detonation waves in a RDRE by tracking each individual wave and recording its position, velocity, and peak intensity as it travels around the annulus. This information is retrieved by a non-intrusive method consisting of using a data mining technique, the k-means algorithm, to distinguish each detonation from each other in a particular frame. An algorithm was then developed to match the detonations of a current frame to the ones of a previous frame. The code was validated against results found from the back-end imaging method developed by the Air Force Research Laboratory with excellent agreement. Results for two and three-wave mode cases show that the instantaneous detonation wave speeds oscillate around the mode locked average wave speed computed from a detonation surface. Moreover, the investigation of the relationship of the detonation’s peak light intensity with the azimuthal position revealed to also be oscillatory but more distinct.