Noise-resistant two-wavelength interferometry for single-shot measurement of high-gradient flows

0576506 - ÚT 2024 RIV NL eng J - Journal Article
Psota, P. - Çubreli, G. - Šimurda, David - Šidlof, P. - Kredba, J. - Stašík, M. - Lédl, V.
Noise-resistant two-wavelength interferometry for single-shot measurement of high-gradient flows.
Optics and Lasers in Engineering. Roč. 164, May (2023), č. článku 107505. ISSN 0143-8166. E-ISSN 1873-0302
R&D Projects: GA MŠMT(CZ) LTAUSA19036
Institutional support: RVO:61388998
Keywords : high-speed * two-wavelength interferometry * noise-resistant * supersonic * compressible flow * wind tunnel
OECD category: Applied mechanics
Impact factor: 4.6, year: 2022
Method of publishing: Open access
https://www.sciencedirect.com/science/article/pii/S0143816623000349?via%3Dihub

This paper presents a new robust approach to measuring dynamic phenomena with high gradients using two-wavelength high-speed interferometry. A multiplexed interferogram with two different wavelengths and spatial-carrier frequencies is captured by a single high-speed camera shot. Quantitative processing of the interferogram is based on Fourier analysis, which is followed by a robust procedure to retrieve the unwrapped phase map with single-wavelength accuracy but with an extended range of unambiguity. This method is significantly more noise-resistant than the standard two-wavelength technique, which is sensitive to noise and synthetic phase distortion. The method was successfully applied to studying shock waves in a transonic compressor blade cascade in an industrial aerodynamic laboratory, where single-wavelength and standard two-wavelength approaches fail.
Permanent Link: https://hdl.handle.net/11104/0349332