Measurement of continuous pressure and shear distributions using coating and imaging techniques

Abstract

The pressure-sensitive paint (PSP) method and the shear-sensitive liquid crystal coating (SSLCC) method were sequentially applied to measure the areal pressure and shear stress vector distributions on a planar test surface beneath an inclined, axisymmetric, turbulent impinging jet. The combined results provide the e rst-ever consolidated measurements of the continuous normal and tangential force distributions beneath a fundamental e owe eld. Results indicate that the PSP method can be extended to the measurement of small pressure differences (<» 0:1 psig)encountered in low-speed atmospheric e ows. Further, these results provide the e rst demonstration of the capability of the SSLCC method to measure continuous shear stress vector distributions on planar surfaces beneath e owe elds where shear vectors of all possible orientations are present.