Hydrodynamic and Cavitation Characteristics of Static Models of Apparat-uses with Variable Inlet Channel Configurations

Authors

DOI:

https://doi.org/10.20535/2521-1943.2025.9.1(104).318233

Keywords:

hydrodynamic cavitation, vapor-gas fraction, hydrodynamics, numerical methods, cavitation number

Abstract

Numerical calculation methods are an effective tool for developing new designs and analyzing and comparing existing designs of cavitation devices. The advantage of these methods is the ability to determine rational hydrodynamic parameters for different models without consuming materials and energy. The issue of improving the designs of cavitation devices to ensure a stable cavitation process and optimize their operation in various technological environments remains relevant today. One of the key aspects is the influence of the geometric characteristics of the device’s internal channel on the formation and distribution of the vapor-gas fraction, which directly affects the efficiency of the cavitation process.
To analyze the conditions of cavitation occurrence and compare the hydrodynamic parameters and volumes of the vapor-gas fraction in models of cavitation devices with different geometries of the internal channel of the confuser.
Numerical modeling was performed using the Flow Simulation module with the Navier-Stokes equations, equations of state that determine the physical properties of the fluid, as well as empirical dependences of density, viscosity, and thermal conductivity on temperature.
In all the studied structures with obstacles, a vapor-gas fraction is formed at Q = 0.002 m3/s. Stable cavitation occurs at
Q = 0.003 m3/s, with the volume of the formed vapor-gas phase for the model with a cone-shaped obstacle being Vv.f. = 5.39×10−6 m3 for the structure with a screw Vv.f. = 4.91×10−6 m3, and for the apparatus with a double cone Vv.f. = 3.77×10−6 m3. For comparison, the volume of the vapor-gas fraction for the model without obstacles is Vv.f. = 2.93×10−6 m3. The analysis of the histograms of the distribution of the vapor-gas fraction along the diffuser shows that installing a cone obstacle increases the volume of the vapor-gas fraction along the diffuser, ensuring a stable cavitation process. The screw obstacle creates localized areas characteristic of pulsations and disruptions. The double cone demonstrates smaller volumes of the vapor-gas fraction and a uniform increase and decrease in concentrations along the diffuser.
The obtained results can be used to improve and implement the design of static devices that ensure a stable cavitation process and optimize their operation under the conditions of certain technological environments.

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Published

2025-03-18

How to Cite

[1]
D. Vitenko and N. Zvarych, “Hydrodynamic and Cavitation Characteristics of Static Models of Apparat-uses with Variable Inlet Channel Configurations”, Mech. Adv. Technol., vol. 9, no. 1(104), pp. 73–82, Mar. 2025.

Issue

Vol. 9 No. 1(104) (2025)

Section

Mechanics

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Copyright (c) 2025 Дмитро Вітенько, Наталя Зварич

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