For better understanding of the sound absorption mechanism of resonator with multi slits under high incident sound pressure level(SPL)
direct numerical simulation(DNS) using low dispersion and low dissipation computational aeroacoustics(CAA) method was carried out to deal with 2-D resonator with multi slits. Good agreement was first found in validation of standard resonator with single slit through comparison. Then the same numerical methods were applied in numerical simulation of multi slits resonators with the same perforation ratio. Results show that under high SPL
vortex shedding contributes dominantly to the sound absorption coefficient
over 68% in each incident frequency. Multi slits could enhance the viscous dissipation of acoustic energy while vortex shedding was suppressed in low frequencies and strengthened in high frequencies
resulting in better sound absorption capability of resonator with multi slits in relatively higher incident frequencies
but with weak influence on low incident frequencies.