DIMPLE GENERATOR OF VORTEX STRUCTURES

  • A. V. Voskobijnyk Institute of hydromechanics NASU, Kyiv, Ukraine
  • V. M. Turick NTUU “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine
  • O. A. Voskoboinyk Institute of hydromechanics NASU, Kyiv, Ukraine
  • V. A. Voskoboinick Institute of hydromechanics NASU, Kyiv, Ukraine
Keywords: hemispherical dimple, visualization, velocity and pressure fluctuations, vortex structures, correlation, spectrum

Abstract

The paper presents the results of experimental studies of the space-time characteristics of the velocity and pressure field inside a hemispherical dimple on a flat surface. The features of the formation and development of vortex structures generated inside the dimple, as well as their interaction with the streamlined surface of the dimple and the boundary layer were established. Integral, spectral and correlation characteristics of the field of velocity, dynamic and wall pressure fluctuations were obtained. The velocities and directions of transfer of large-scale vortex structures and small-scale vortices inside the dimple were determined. The frequencies of rotations and ejections of large-scale vortices, the frequencies of oscillations of the vortex flow inside the dimple and self-oscillations of the vortex structures of the shear layer, their subharmonics and harmonics of higher orders were established.

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Published
2021-07-21
How to Cite
Voskobijnyk, A., Turick, V., Voskoboinyk, O., & Voskoboinick, V. (2021). DIMPLE GENERATOR OF VORTEX STRUCTURES. Journal of Numerical and Applied Mathematics, (1 (135), 95-102. https://doi.org/10.17721/2706-9699.2021.1.12