The introduction of energy- and resource-saving technologies into the technological processes of the oil and gas industry corresponds to the energy strategy of the Russian Federation for the period up to 2035, approved by the Decree of the Government of the Russian Federation No. 1523-r dated 09.06.2020. The use of secondary effects accompanying cavitation expiration is promising. Cavitation is widely used in many areas of the oil and gas industry as an intensifying factor due to the erosive effects that occur in multiphase flows due to numerous microhydrostrokes - pressure surges resulting from the closure of caverns, accompanied by the formation of shock waves and high-speed micro-jets of high intensity.
The methods for calculating the cavitation number proposed by various researchers are analyzed. The flow rate, or the corresponding pressure drop at which cavitation begins, is usually called the initial condition. It is important to determine this state in order to prevent the manifestation of cavitation for a number of technical applications (in cases where liquid separation and cavitation erosion cannot be allowed), or, conversely, to effectively generate cavitation to intensify the corresponding processes (cavitation erosion, dispersion, emulsification, etc.). An experimental setup has been developed to study the processes of the origin and development of hydrodynamic cavitation by visual methods and the evaluation of the spectrum of acoustic vibrations. The initial (critical) parameters of cavitation nucleation for nozzles of various profiles have been determined analytically, experimentally and numerically. It is established that the analytical determination of the cavitation number is clearly insufficient to predict the cavitation/cavitation-free regime of fluid flow. The results obtained make it possible to predict the presence/absence of hydrodynamic cavitation in practical applications in the oil and gas industry.
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