A New Mathematical Model for the Features of Bubble Collapse in Steam Cavitation Processes

This study presents a novel mathematical model for bubble cavitation, demonstrating its application in the numerical simulation of steam bubble dynamics within hydrodynamic cavitation phenomena. While previous research has largely focused on the negative consequences of cavitation or its industrial applications, a key unresolved issue remains the physical mechanism of bubble destruction during collapse. This paper investigates the conditions leading to the instability of a spherical bubble’s surface, which in turn causes its irreversible collapse. The model is based on the hypothesis that a bubble is destroyed when its surface temperature exceeds a critical value (Tcr). The modified model, which accounts for heat and mass transfer processes at the bubble boundary, was used to analyse the behaviour of bubbles under different flow conditions. Our computational experiments show that the bubble collapses when the surface temperature surpasses the critical point, irrespective of its size. A comparison of theoretical and experimental data on bubble behaviour during hydrodynamic cavitation validates the proposed criterion. Specifically, the collapse of bubbles in the Venturi tube upon exceeding a critical temperature is shown, supported by experimental data with a maximum error of 6%.The results suggest that the hydraulic parameters of the flow are key factors determining the intensity of cavitation, and that the fulfillment of the condition Ts ≥ Tcr (Tcr = 647 K, pcr = 22.5 MPa) can serve as a reliable criterion for bubble destruction.