Numerical simulation of unsteady cavitating jet by a compressible bubbly mixture flow method

Asian Working Group- IAHR's Symposium on Hydraulic Machinery and Systems

Peng, G.^1 ; Oguma, Y.^1 ; Shimizu, S.^1

Department of Mechanical Engineering, College of Engineering, Nihon University Tamura-machi, Koriyama, Fukushima

963-8642, Japan^1

关键词: Bubble cavitation;    Compressible mixtures;    Computational results;    Expansion and contraction;    High speed water jet;    Intensive cavitations;    Submerged water jet;    Two phase mixtures;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/163/1/012037/pdf
DOI  :  10.1088/1755-1315/163/1/012037

来源: IOP

【 摘 要 】

Focused on the unsteady behaviour of high-speed water jets with intensive cavitation a numerical analysis is performed by applying a compressible mixture flow method combined with a simplified bubble cavitation model. The mean flow of two-phase mixture is calculated by URANS for compressible flow and the intensity of cavitation in a local field is evaluated by the volume fraction of gas phase varying with the expansion and contraction of bubbles the mean flow field. High-speed submerged water jet issuing from a sheathed nozzle is treated when σ = 0.1 and Re = 4.5x105 . The distribution of cavitation clouds predicted approximately agrees with experiment data of visualization observation and the unsteady behaviour of cavitation cloud shedding is captured acceptably. Computational results reveal that cavitation occurs at the entrance of nozzle throat and bubble clouds expand and develop while flowing downstream along the boundary layer. Developed bubble clouds split into small blocks and sheds downstream periodically near the exit of sheath.