Laminar oscillatory flow of an incompressible fluid through a sharp-edged sudden contraction of a circular tube is studied.
Elucidation of the dynamic behaviors of the flow is indispensable for improving the characteristics of the hydraulic components. In this paper, numerical solutions of the oscillatory flow field are obtained by an implicit finite difference method, and the axial velocity profiles of the oscillatory flow super imposed on a steady flow are measured by means of a laser Doppler method. The results obtained ascertain that there is a good agreement with each other.
The numerical results obtained indicate that at a Reynolds number less then 800 no flow separation occurs near the sharp-edged corner of the flow field. It is also concluded that the oscillatory velocity profiles near the entrance are not dependent on the Reynolds number and frequency, but only on the axial position.

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