Background: Cavitation-jet deaerators are known. In them, the process of desorption of dissolved gases occurs when superheated water boils, which is directed in the form of a swirling vortex flow into the rarefaction zone. The vapor-gas mixture is discharged from the cavitation cavity, which is formed along the axis of the vortex flow. Cavitation-jet deaerators, as well as other direct-flow deaerators, are characterized by relatively low efficiency. However, they are small in size and can work without supplying a heating medium. This allows the use of these deaerators in those technological systems in which it is impossible to apply effective thermal deaerators of other types. The expansion of the scope of practical application of cavitation-jet deaerators is hampered by the lack of an appropriate mathematical description that would allow us to solve the problems of their schematic and constructive improvement. One of the main tasks in this case is to calculate the static pressure field of the liquid phase in the active zone of the deaerator.
Materials and methods: Modeling the hydrodynamic situation in the active zone of a cavitation-jet deaerator is based on the numerical solution of the Navier-Stokes equations and the continuity equation. These equations are written in the Reynolds decomposition. In this case, the standard k-ε turbulence model is used to obtain a preliminary solution, which is then refined during the transition to the SST turbulence model. The model is implemented by means of a specialized software package for calculating fluid flows FlowVision.
Results: A simulation model of the cavitation-jet deaerator core has been developed. The model makes it possible to determine the hydrodynamic characteristics of water flows and a gas-vapor mixture with a change in the design of elements, the mode of supply of the source water and the removal of gases..
Conclusions: It was found that the removal of the vapor-air mixture has practically no effect on the nature of the change in the total and excess static pressure of the flow along its movement in the active zone of the deaerator. The effect of deaeration is due to a change in static pressure in the liquid phase due to a decrease in static pressure in the vapor phase inside the active zone of the deaerator. The change in the static pressure in the liquid phase in the radial direction from the internal to the external boundaries of the flow is relatively small. A significant dependence of the static pressure in the vapor phase inside the core on the hydraulic resistance of the exhaust gas path.