Multiphysics coupled optimization and radiation analysis of a pentamode matching layer for airborne electromagnetic pulse acoustic sources

Airborne electromagnetic pulse acoustic sources face a severe impedance mismatch, causing low energy transmission efficiency. This work proposes a pentamode matching layer design using multiphysics coupling. We develop a finite element model integrating circuit, electromagnetic, structural, and acoustic fields, and employ a genetic algorithm to optimize matching layer parameters. Results demonstrate that the optimized pentamode layer significantly increases peak sound pressure and reconfigures resonance frequencies with new band peaks. Analysis reveals an inertial-cavity coupling effect between layer and plate that enhances both high- and low-frequency radiation, improving radiation intensity, spatial directivity, and electromagnetic-acoustic conversion efficiency. This study provides a new theoretical basis and structural design approach for efficient radiation of electromagnetic pulse acoustic sources in air, and it has important scientific significance and engineering application prospects.