DAMPED OSCILLATIONS IN A CONNECTED FLUID SYSTEM,

Abstract

Damped fluid oscillations in a system consisting of two tanks with different diameter connected with a pipeline are treated. The equations for the oscillation of the fluid system were derived from the energy equation for instationary flow and the continuity equation for incompressible fluid. The energy losses due to friction in the tanks are negligible compared with those in the pipeline due to the difference in their diameters. Furthermore a smooth inlet (outlet) was assumed in order to neglect these energy losses, too. The arising differential equations are nonlinear and were solved by a perturbation method. The results show that the damped natural frequency differs hardly from the undamped natural frequency and that the logarithmic decrement is small and decreasing with flight time. However, the flow in the pipeline is probably turbulent and with inclusion of the friction terms neglected in the analysis the damping will be higher than the calculated one. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1959
Accession Number
AD0629275

Entities

People

  • Helmut F. Bauer

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Continuity
  • Diameters
  • Differential Equations
  • Equations
  • Frequency
  • Friction
  • Inclusions
  • Lepidoptera
  • Mathematics
  • Oscillation
  • Perturbations
  • Pipelines
  • Resonant Frequency

Readers

  • Control Systems Engineering.
  • Fluid Dynamics.
  • Plasma Physics.