Full-field pressure and strain measurement technique using a dual-layer luminescent coating

Abstract

This paper reports on the combination of two surface measurement techniques, pressure-sensitive paints (PSPs) and photoelastic coatings (PECs), to measure full-field, dynamic pressure and strain fields. The technique applies a fast PSP onto the surface of a PEC adhered to the test specimen. A dual light-emitting diode approach is used to overcome poor polarization retention of the PSP luminophore. The theory of the technique is presented. Experiments and corresponding results on a vibrating cantilever beam specimen placed within a pressure chamber and driven near resonant frequency as well as on an inclined flap in supersonic flow demonstrate the feasibility and current limitations of the technique. Sensitivity and interference effects are discussed.