Shadowgraph Imaging of Cavitating Jet

Ryuta Watanabe¹, Takayuki Kikuchi¹, Takayuki Yamagata², Nobuyuki Fujisawa²

¹Graduate School of Science and Technology, Niigata University, Niigata, Japan.
²Visualization Research Center, Niigata University, Niigata, Japan.

DOI: 10.4236/jfcmv.2015.33010                

Abstract

This paper deals with the statistical properties of unsteady structure of cavitating water-jet issuing into a stagnant fluid of water using the shadowgraph imaging combined with the proper orthogonal decomposition (POD) analysis. The experimental result indicates that the cavitating jet is composed of axisymmetric mode, while the periodic axial oscillation is found along the jet centerline. The reconstructed cavitation images show the presence of growing, shrinking and shedding motion in the cavitation cloud, which sustains a periodic behavior of the cavitating jet.

Keywords

Cavitating Jet, POD Analysis, Shadowgraph, Periodic Structure

Conflicts of Interest

The authors declare no conflicts of interest.

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