Numerical Simulation of Flow Field of Submerged Angular Cavitation Nozzle

• Published in: Applied sciences Vol. 13; no. 1; p. 613
• Main Authors: Dong, Wenqiang, Yao, Ligang, Luo, Weilin
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2023
• Subjects: Accuracy; angular cavitation nozzle; Cavitation; cavitation jet; Contraction; Efficiency; Experiments; K-epsilon turbulence model; Mathematical models; Mixtures; Nozzle geometry; Nozzles; numerical simulation; Optimization; Pressure distribution; Rigid walls; Simulation; submerged environment; Turbulence models; Velocity; Viscosity; Vortex rings
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app13010613

A model of a submerged angular cavitation nozzle is established, which consists of a contraction part, parallel middle part, and expansion part. Based on the CFD technique, a numerical simulation of the flow field of the submerged cavitation nozzle is carried out, in which a multiphase mixture model, cavitation model, and renormalization group (RNG) k-ε turbulence model are applied. Considering the influence of mixture density on cavitation, the effects of the inlet contraction part, parallel middle part, and outlet expansion part on the velocity and vapor volume fraction are studied. The numerical simulation results show that the mixture density is essential in the cavitation jet. When the nozzle diameter d is fixed, the designed angular cavitation nozzle with contraction angle α = 13.5°, parallel middle part length Ld = 3d, expansion part length Le = 4d, and expansion angle β = 60° can effectively bring out cavitation. A cavitation cloud is produced near the rigid wall of the outlet expansion section and diffuses in a vortex ring shape. Optimizing the nozzle structure can improve the cavitation effect of the nozzle. The feasibility of this model is verified by relevant experimental data.