CHANGING ENERGY ACCELERATED TURBULENT FLUID FLOW IN THE PIPELINE ACCORDING TO SPECTRAL ANALYSIS

Authors

  • Р. М. Гнатів Lviv Polytechnic National University, Lviv, Ukraine
  • М. М. Босак Lviv Polytechnic National University, Lviv, Ukraine

DOI:

https://doi.org/10.20535/2305-9001.2014.72.38115

Keywords:

unstable, unsteady, fluid motion, spectral analysis, the change in energy

Abstract

According to the results of theoretical and experimental studies of accelerated fluid flow in a cylindrical pressure pipe made a qualitative assessment of the spectral composition of the energy of turbulent flow. Density spectra obtained at different distances from the pipe wall. According to estimates, the transfer of energy between the low and high frequencies in unsteady flow significantly different from the energy transfer in a steady stream. In the transition to the low-frequency components of turbulent currents of the spectra in the near-wall local rate of flow with a relatively large part of the total energy than in the core flow. In steady flow relative share of low-energy component decreases with the increase of average flow velocity (number Re). Transient currents reverse process occurs after the turbulence of flow turbulence is a small-scale and large-scale development of the current portion of the increase

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Published

2015-02-23

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