Rocket engines contain confined combustion systems, which are essentially combustion chambers. In these chambers, nonlinear interactions among turbulent fuel and oxidizer flows, sound waves, and heat produced from chemical reactions cause an unstable phenomenon called “combustion oscillations.” The force of these oscillations on the body of the combustion chamber—the mechanical stress on the chamber— is high enough to threaten catastrophic failure of the engine. What causes these oscillations? The answer remains to be found.
Click here for original story, Finding the cause of a fatal problem in rocket engine combustors
Source: Phys.org