^{1}Kubenko, VD^{1}S.P. Timoshenko Institute of Mechanics of the NAS of Ukraine, Kyiv |

Dopov. Nac. akad. nauk Ukr. 2017, 9:41-47 |

https://doi.org/10.15407/dopovidi2017.09.041 |

Section: Mechanics |

Language: Russian |

Abstract: The semiinfinite circular cylindrical cavity filled with ideal compressible fluid and containing a spherical body, whose surface is energized with the set frequency is observed. It is required to build a wave potential for the observed area for the purpose of definition of the influence of the end face of the cylinder on the fields of pressure and velocity in the system. The matching boundary problem for the equation of Helmgoltz is formulated. The general solution is built in the form of a superposition of the potentials written with the use of cylindrical and spheri cal wave functions. “The imaginary” sphere, with which the condition in the face cross-section of the cylinder is realized, is introduced. Redecomposition of spherical wave functions is applied to satisfy the boundary conditions on cylindrical ones and on the contrary, and the theorems of addition of spherical functions are used. As a result, the problem is reduced to the solution of an infinite system of algebraic equations, which can be solved by the truncation method. |

Keywords: compressible liquid, semiinfinite cylinder, vibrating spherical particle |

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