Error analysis of pressure-sensitive paint measurement

Pressure-sensitive paint (PSP) is a useful measurement technique to obtain the pressure distribution on a surface, and has been applied to many measurements in wind tunnel testing. The measurement error of PSP has not been discussed in most reports, while the evaluation of the error is very important for quantitative measurements. In this study, we propose the calibration method which enables us to find the defect of PSPs or the failure of the calibration tests easily. Based on the first- and second-order polynomial Stern-Volmer equations, the propagation of error is analyzed. As a result, it is clarified that the experimental values must be fitted by the Stern-Volmer equations with the constraint condition of (p/pref, Iref/I) = (1, 1) at T = Tref , and the relative error in pressure can be reduced. It is also shown that the error becomes quite large when p/pref ≈ -B/2C in the second-order polynomial Stern-Volmer equation. We propose an indicator for the choice of the polynomial order of the Stern-Volmer equation at T/Tref ≈ 1, p/pref ≈ 1.