Static Pressure Extraction from Velocimetry in Vortical Flow Fields

TL;DR

This paper presents a novel method for extracting static pressure fluctuations in vortical flows from velocity measurements without needing boundary data, validated through numerical simulations and applied to rotor blade flow.

Contribution

It introduces a boundary-independent technique using velocity fields and streamline curvature to determine static pressure in vortical flows.

Findings

Effective in sparsely seeded regions and recirculation zones

Validated with flow around a circular cylinder

Successfully applied to rotor blade vortical flow

Abstract

Rapid fluctuations of static pressure away from flow boundaries in a low-speed vortical flow, are extracted using the measured velocity field. The technique departs from prior work in not requiring far boundary values. Stereo Particle Image Velocimetry data satisfying the continuity equation are used as input to a Navier-Stokes solver. Streamline curvature, inspired by the Polhamus suction analogy, is used to determine the pressure inside recirculation regions. The technique is validated numerically using the flow around a circular cylinder before being applied to the vortical flow beneath the sharp edge of a rotor blade in reversed flow. The technique proves effective for sparsely seeded regions including recirculation zones and shear layers in vortices.