A. G. Khakimov

DETERMINING THE PARAMETERS OF A PIPE SYSTEM CONTAINING FLUID FLOW BY NATURAL FREQUENCIES OF FLEXURAL VIBRATIONS

The investigation deals with natural frequencies of flexural vibrations in a pipe system containing pressurized fluid flow and clamped at both ends. It has been found that an increase in the axial load results in higher natural frequencies of pipe flexural vibrations. The research has shown that an increase in the pipe wall thickness results in lower natural frequencies of flexural vibrations under tensile axial loading and higher natural frequencies of flexural vibrations under compressive axial loading. It has also been found that an increase in fluid density or pressure within the pipe system results in lower natural frequencies of pipe flexural vibrations.

Using two natural frequencies of pipe flexural vibrations, we can determine axial load and pipe wall thickness, or axial load and fluid density within the pipe system, or fluid density within the pipe system and pipe wall thickness, or fluid pressure and density within the pipe system, or fluid pressure and pipe wall thickness.

The investigation outcomes can be applied for assessing axial load and pipe wall thickness, or axial load and fluid density within a pipe system, or fluid density within a pipe system and pipe wall thickness, or fluid pressure and density within the pipe system, or fluid pressure and pipe wall thickness using two natural frequencies of flexural vibrations.

Acknowledgments: The study was financed by the federal budget according to state assignment No. 0246-2019-0088) and supported by RFBR grant No. 18-01-00150.

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