Abstract
In this paper, we will introduce an analytical aproach to characterize the behavior of the swirling annular jet in the vortex proximity sensor and to determine the pressure.
First, knowing the strength of swirl and the annular width at the issue, we assume that the momentum and the angular momentum are conserved, the rate of increase of flow is proportional to the velocity on the main flow line, the pressure of the bubble is constant and acts perpendicularly to the main flow line, etc. Under these assumptions, the geometry of the main flow surface, the velocity decay and the increase of the annular width along it are described, though the pressure is unknown.
Next, in order to determine the pressure, supposing a control volume enclosed by two concentric cylinders pancaking the annular jet and two planes with small angles to each other at the center line, then in this volume the radial components of the momentum are tested.
Last, some numerical and experimental results are shown and discussed.
