Adaptive particle swarm algorithm for solving three-dimensional coordinates of infrasound sources based on acoustic field velocity potential theory

Excessive external loads on rock and soil in hazard-prone areas generate low-frequency infrasound through molecular-scale friction and fracture. This infrasound serves as a precursor to geological disasters. This study presents a novel infrasound source localization method utilizing a compact 6-sensor array. From an aerodynamic perspective, this work establishes a velocity potential theory for homogeneous media in both free and half space, deriving nonlinear Equations relating sound pressure, particle velocity, and velocity potential. An Adaptive Particle swarm algorithm (APSO) is proposed to efficiently solve these Equations, enabling accurate localization of the infrasound source. Simulations for single-frequency and broadband point sources were conducted, yielding 3D spatial scatter plots of source locations with acceptable accuracy. Furthermore, Sensitivity analyses and robustness tests show that the method maintains reliable accuracy even under noise interference. The method demonstrates significant value for monitoring, early warning, and advanced prevention of geological hazards.