Thermoacoustic instabilities in combustion of lean gaseous premixtures are the major problem to counteract when aiming for low-NOx emissive combustion systems.
There are many possible ways under intense worldwide investigation. Some ways are active noise suppression or compensation, some are passive.
Within a DFG graduate college partial project, ZARM examines the capabilities of sound absorbing heat shielding ceramics for high-pressure and high-temperature combustion chambers. This is a new approach to passive damping of combustion noise.