Oscillatory flow through a convergent tube.

Abstract

This paper deals with the laminar oscillatory flow of an incompressible fluid through a slightly convergent tube. The velocity distributions in the convergent tubes, whose convergent angles are in the range of 24°, are measured by a Laser Doppler Velocimeter. The flow in the convergent tube is numerically analysed by a finite difference method (SOR), without neglecting the convective terms in the Navier-Stokes equation. Experimental results agreed well with the numerical ones. The velocity profile of a laminar oscillatory flow in the convergent tube is quite different from the velocity profile in a straight tube of circular cross-section, even if the convergent angle is very small. The instantaneous pressure distribution in the convergent tube is uniform at each cross section as in a straight circular tube.