This work represents the results of a study of the acoustic characteristics of a room, which is intended (with appropriate additional equipment), according to the project, for the studies of the characteristics of various types of machines of small dimensions. The obtained results show us, that the investigated room, in case the sound-scattering boards with sound-reflecting elements are installed inside, could be attributed to the category of «Echonic» rooms, with the parameters close to reverberation chambers. Therefore, this allow one to carry out practical works to reduce the noise of machines and equipment that do not have high directivity indicators. At the same time, works aimed at reducing the noise of machines in such a «live» room are less laborious compared to similar work in echo-free chambers. Besides, such rooms are less fire hazardous.

The considers the actual problem of determining the dispersed composition of the gas phase in a liquid medium. The work uses a passive acoustic method based on the interaction between the vibration frequency of bubbles and their size. On the experimental setup, acoustic waves emitted by air bubbles in water were recorded using a hydrophone. The sizes of the bubbles were determined by the spectra of the recorded signal. In the course of the experiments, the bubble radius was varied from 1.7 to 2.4 mm. The spectrogram of the signal was used to estimate the intensity of the release of bubbles in the volume of the experimental apparatus. Using the technique of synchronous filming, a video recording of the process of bubbles allocation at the apparatus was made. The analysis of the recorded video showed the correspondence of the determination of the parameters of the liquid-gas mixture. There are proposed various application scenarios of the passive acoustic method in the oil and gas industry.

The article presents the experimental studies of sound insulation of a single-layer barrier made of gypsum wall boards with a thin-layer coating. The coating consists of a viscous base and glass airless microgranules. The coating increases the efficiency of reducing air noise. The material is applied as a normal paint by spraying on the surface. The research results have been obtained in an acoustic reverberation chamber designed to study the partition walls effectiveness.