The impact of obstacle parameters on mid-high frequency noise propagation in comprehensive mining workfaces and safety implications

Noise pollution in fully mechanized mining workfaces threatens the occupational health and safety of miners. Obstacles such as mechanical equipment and pipelines in roadways can alter noise propagation patterns, and clarifying this influence is crucial for mine noise control and personal protection. This study established numerical simulation models for medium- and high-frequency noise propagation in fully mechanized mining workfaces using the finite element method and ray acoustics method within the acoustic module. The reliability of the models was validated by comparing the simulation results with field measurement data from test roadways. On this basis, the influence laws of key parameters such as obstacle obstruction rate, shape, number, and spacing on noise propagation were analyzed. The results show that the obstruction rate and shape of obstacles have a weak impact on the attenuation of mid-to-high-frequency noise, and the noise reduction effect is negligible. When the number of obstacles is fixed, a spacing of 1m achieves a significant noise reduction effect on high-frequency noise (sound pressure level change of approximately 20 dB) but has little impact on mid-frequency noise at 2000 Hz. The number of obstacles significantly affects high-frequency noise, and the optimal configuration is related to spacing—under a spacing of 1m, a single obstacle can achieve significant noise reduction (>10 dB); under a spacing of 3m, 1 or 4 obstacles yield the optimal effect (approximately 20 dB), while their impact on mid-frequency noise is negligible. The research results provide a key basis for mine noise control and obstacle configuration optimization, and have practical value for improving the occupational health protection of miners and ensuring the safe production of coal mines.