THE DYNAMIC CHARACTERISTICS OF TAPERED FLUID LINES WITH VISCOE-LASTIC PIPE WALLS (TRANSFER MATRIX AND FREQUENCY RESPONSE)
Keywords:fluid power systems, tapered fluid lines, transfer matrix equation, viscoelastic pipe wall, frequency response
For convenience in investigating the dynamic responses of a liquid-filled tapered line with a viscoelastic pipe wall, a transfer matrix equation, relating pressure to volumetric flow, is derived. In this derivation, it was assumed that the rate of divergence (or convergence) of the line is comparatively small. The fluid line model employed in the analysis is one of an unsteady viscous flow; that is, the frequency-dependent effect of viscosity is taken into consideration. The visco-elastic pipe wall model is a modified version of the Voigt mechanical model, and it is distributed along the pipeline. The frequency response curves are calculated from the matrix, and the accuracy of the curves is evaluated by comparing them with the response curves obtained without assuming the small taper angle. The results verify that the transfer ma-trix is accurate enough for practical applications.
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