Application of median filter technique and ESP in PSP data processing

In this paper, the application of PSP(Pressure Sensitive Paint) technique is described in wind tunnel. As a new optical pressure sensor technique, there are some problems needed to be solved, the big noise and SE(Systematic Error) in the PSP pressure measurement system are two of them, the median filter technique is applied to eliminate the big noise and ESP technique is introduced to decreased the SE. The gray value of the filtered pixel in the PSP image is determined by neighborhood of the pixel, so it preserves the correlation info contained in the pixels. “PSP Processing System Software” developed by ourselves is used for processing images by median filter technique, and comparison results between the raw data and the filtered data of PSP images is given, meanwhile, to a certain pressure test section, the Cp (Pressure Coefficient) data corrected by ESP data from PSP technique and the data from ESP (Electronically-scanned Pressure) technique are compared.