As a component of measuring velocity of flow and controlling flow, venturi tube has been widely used in many fields such as hydropower and shipping due to simple structure and small pressure loss. However, the unique structure of the venturi tube makes it extremely susceptible to cavitation in the throat, which can be accompanied by high instantaneous pressures. On the one hand, numerical simulation of cavitation flow field can weaken cavitation to avoid cavitation erosion and improve the accuracy of flow measurement and the service life of components. On the other hand, cavitation can be intensified and the energy generated when cavitation occurs can be used to develop other processes for the purpose of energy-saving. Therefore, this paper carries out a single factor numerical simulation of the cavitation flow field in the venturi tube based on the Standard k-ε turbulence model for mixtures in FLUENT. The effect of a single variable on the cavitation flow field in the venturi tube was compared and analyzed by varying the values of the contraction angle, diffusion angle and inlet pressure. The numerical results show that if the length of the venturi tube is kept constant, the highest cavitation intensity are obtained when the contraction angle ranges from 40° to 50° and the diffusion angle ranges from 17° to 20°. If the outlet pressure of the venturi tube is kept constant, the lower the inlet pressure is, the weaker the cavitation intensity is within a certain range. Increasing the inlet pressure can improve the cavitation efficiency and increase the cavitation intensity. There exists a minimum inlet pressure to achieve the optimal cavitation effect for the venturi tube with a certain structure. The research in this paper is not only beneficial to the study of cavitation phenomenon, but also provides a reliable basis for the improvement of venturi tube structure on various types of equipment.
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