Study on Acoustic Characteristics of Environmental Noise in Low Pressure Enclosed Spaces

In order to study the impact of low pressure environment on acoustic measurement, different pressure environments were simulated in a low pressure experimental chamber to conduct measurement research on environmental noise under low pressure environment. The measurement equipment used DS-2MC1001-W microphone, and the sound source output was environmental noise. The pressure inside the test chamber was reduced from 101kPa to 1kPa, and a set of data was measured every 10kpa. The acoustic characteristics of the measured data were recorded, including pitch frequency, sound pressure level Analyze the acoustic data of environmental noise at different pressure levels from the perspective of A-weighted sound pressure level and 1/3 octave A-weighted sound pressure level, and explore the attenuation of environmental noise at different pressure levels and the main frequency bands of noise. The research results indicate that as the air pressure decreases, all of the above parameters decay. When the air pressure drops to 1kPa, the sound pressure level decreases by 8.31dB, and the A-weighted sound level decreases by 8.41dBA. Among them, the sound source noise is mainly in the frequency range of 0-4000Hz.