A rotating detonation combustion (RDC) system including a detonation chamber wall extended along a longitudinal direction. The detonation chamber wall defines a detonation chamber radially in between the detonation chamber walls. The RDC system further includes a fuel-oxidizer nozzle defining a first convergent-divergent nozzle disposed upstream of the detonation chamber, and a gas nozzle defining a second convergent-divergent nozzle extended through the detonation chamber wall at least partially along the longitudinal direction. The gas nozzle provides a flow of gas into the detonation chamber at least partially co-directional to the detonation chamber wall.