Hydrophysics

Hydrophysics

Numerical Investigation of the Effect of Disk-Shaped Cavitator Hole Diameter on Drag Force and Cavity Shape

Document Type : Original Article

Author
Ehsan Yari
Faculty of Mechanics .Maleke Ashtar University of Technology
Abstract
Supercavitating a hydrodynamic process in which the body is completely surrounded by a layer of gas and its formation is the result of cavitators installed in front of the body. Supercavitating vehicles can move in water bodies with high speeds and thus significantly reduce frictional resistance. One of the most cavitators used in practical applications is perforated disk-shaped cavitator, which is analyzed in this article. Sensitivity of geometrical and flow parameters and their impact on the geometry of the cavity (bubble) and the rate of mass transfer, are the most important variables which have been discussed in this study. Numerical analysis has been performed using computational fluid dynamic based on finite volume method with the help of Ansys-Fluent software. The k-ε model is used to model the turbulent fluid flow. The generated network is structured around the cavitator and across the entire network solution domain. To validate the numerical results, two geometries including a rectangular surface with attack angle of 10 degrees and disk cavitator have been used. According to the obtained results, there is good agreement between numerical and experimental data. Based on the obtained results for speeds higher than 60 meters per second, using constant correction factors, the resistance level of the super-cavitation bubble can be accurately estimated.
 
Keywords
Super-cavitation
perforated disk-shaped cavitator
Finite volume method
mass transfer
drag coefficient
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  • Receive Date 18 January 2021