Noise Reduction in Helicopter Cabins Using Microperforated Panel Composite Sound Absorption Structures

The high level of noise in helicopter cabins considerably compromises the comfort and safety pilot passengers. To verify feasibility effectiveness microperforated panel composite sound absorption structures for suppression cabins, simulation experimental studies were conducted on a model light cabin. First, three cabin wall designed. Then, finite element main gear/body acoustic vibration coupling was established to obtain target frequencies structures; effect verified via simulation. Finally, equipped with built, test performed. results showed that combined structure panel–porous material realized an overall pressure attenuation 8–10 dB, average, wide frequency range 500–2000 Hz, amplitude more than 20 dB. panel–acoustic supermaterial achieved low-frequency 300–450 Hz. reached 50%, it also exhibited good reduction effects middle- high-frequency bands.