ABSTRACT
More recently, pressure sensitive paint (PSP) has been used in wind tunnel testing[l]. The PSP technique has many advantages over pressure tap technology. The test surface is coated with a paint containing an oxygen-sensitive dye. The luminescence of the dye is quenched by the oxygen in the airf10w around the surface. By imaging the illuminated surface with a ceo camera, the oxygen prolile, and hence the pressure profile of the surface, is mapped. PSP technology is cheaper, non-invasive and relatively easy to apply compared to pressure tap technology, as well as providing a continuous pressure distribution compared with measurements at discrete points[2]. Luminescence quenching atTccts both the intensity and the lifetime or the luminophore and both approaches can be used for PSP applications. Current PSP techniques employ mainly an intensity based approach which is susceptible to drift and aging of both light source and detector as well as effects due to paint inhomogeneities. In this work, a lifetime approach is used which eliminates many of the problems encountered in intensity imaging. Since the lifetimc is an intrinsic property of the luminophore, unlike intensity, it is virtually independent of extemal perturbations.
