Low-Frequency Acoustic Emissions During Granular Discharge in Inclined Silos

In this work, experimental results on the generation of acoustic contributions during the discharge process of different granular materials from both vertical and inclined silos are presented. The experiments show that the generation of acoustic emissions associated with the “silo music” phenomenon occurs not only in vertical silos but also in inclined ones. The acoustic signals produced during the silo discharge process are recorded and analysed in both time and frequency domains. The frequency analysis focuses on low frequencies near the lower auditory threshold of 20 Hz, demonstrating that the spectral components of the acoustic signals are related to the mass flow rate and the discharge velocity of the granular material.