Temperature Correction of Pressure-Sensitive Paint for Industrial Wind Tunnel Testing

Abstract

Pressure-sensitive paint measurement can obtain a much more detailed surface pressure distribution than can be obtained using conventional pressure taps. However, the pressure-sensitive paint is sensitive not only to pressure but also to temperature, and where high accuracy is required, it is essential to compensate for this temperature dependency. This paper discusses data processing methods for pressure-sensitive paint measurement in transonic industrial wind tunnel testing, and proposes three methods to compensate for temperature dependency of the pressure-sensitive paint: an in situ method, an a priori method, and a hybrid of a priori and in situ methods. The pressure distributions from the pressure-sensitive paint data obtained by these proposed methods are compared with pressure tap data measured by conventional pressure transducers, and it is confirmed that the proposed methods are effective in compensating the temperature dependency of pressure-sensitive paint and improve the accuracy of the obtained data. It is also found that the hybrid of a priori and in situ methods is widely applicable to the industrial wind tunnel testing even if the pressure range of the pressure tap data is limited. Nomenclature C p = pressure coefficient C PSP = compensation constant for PSP data C TSP = compensation constant for TSP data f, g = functions of pressure ratio and temperature ratio I = luminescence intensity M = Mach number p = pressure T = temperature x=c = airfoil chordwise coordinate measured from leading edge, normalized by chord = angle of attack = standard deviation Subscripts PT = pressure tap location ref = reference condition in wind tunnel testing refc = reference condition at calibration TM = thermometer location 0 = stagnation condition 1 = freestream conditions

Development of Bi-Luminophore Pressure-Sensitive Paint Systems

“…The various verification tests have been conducted, demonstrating the performance of PSP systems [3], [4]. Our PSP measurement system has been applied to at the 2m x 2m transonic wind tunnel in the development tests of regional jet-type domestic civil transport.…”

A review of pressure-sensitive paint for high-speed and unsteady aerodynamics

“…Various strategies have been developed for coping with the temperature sensitivity of PSP. Researchers have used dual-luminophore PSP formulations to simultaneously sense pressure and temperature, infrared cameras to measure the temperature distribution over a model, or temperature-sensitive paint on half of a symmetric model to provide both temperature and pressure distributions [65][66][67]. All of these techniques involve a determination of the temperature distribution on the model, and a subsequent accounting for the temperature field in a correction of the pressure data.…”

Aeronautics and astronautics: Recent progress and future trends

“…But the pressure-sensitive paint is sensitive not only to pressure but also to temperature. Therefore, when high accuracy is required in multiple varying conditions, it is essential to calibrate and compensate for this temperature dependency [55].…”