Novel strategies for enhancing hydrodynamic cavitation in a circular Venturi for gas hydrate prevention

Abstract

The paper considers the problem of hydrate formation, which leads to a significant decrease in the level of production and the creation of a serious threat to the safety of working personnel. A device based on hydrodynamic cavitation to combat hydrate formation is proposed. Based on the turbulence model of shear stress transfer (SST) k-ù, an improved model of non-isothermal fluid flow is presented for the analysis of cavitation processes in the ANSYS CFX program. The model showed that a change in the design features of the cavitator leads to a change in the intensity of its formation, which, in turn, affects the thermodynamic characteristics of the flow. So, with the ratio of the helicoid surface to the length of the neck equal to 0.75, the length of the cavitation cloud was 154 mm, the maximum value of the average gas fraction content was 38%, and the maximum temperature change in the flow flowing through the cavitator reached 1 K. And with the ratio of the above-mentioned geometric parameters equal to 1, the length of the cavitation cloud reaches 245 mm, the maximum value of the average gas fraction content is 60%, and the temperature change of the flow flowing through the cavitator increases to 2 K. A departure from the zone of possible hydrate formation is achieved by increasing the flow temperature. Keywords: Venturi tube; hydrate formation; CFD modeling; cavitation; cavitator.