Laser doppler velocimetry and confined flows
Abstract
Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary ...focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure.
Keywords:
laser Doppler velocimetry / geometrical optics / fluctuation / cylindrical tube / confined flowSource:
Thermal Science, 2017, 21, Suppl. 3, S825-S836Publisher:
- Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
Funding / projects:
- Application of Novel Measurement and Computational Techniques on Investigation of Air Flow in Ventilation Systems of Energy Extremely Efficient (“Passive”) Buildings (RS-MESTD-Technological Development (TD or TR)-35046)
DOI: 10.2298/TSCI160720278I
ISSN: 0354-9836
WoS: 000418781900024
Scopus: 2-s2.0-85041646006
Collections
Institution/Community
Mašinski fakultetTY - JOUR AU - Ilić, Jelena AU - Ristić, Slavica AU - Srećković, Milesa PY - 2017 UR - https://machinery.mas.bg.ac.rs/handle/123456789/2631 AB - Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure. PB - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd T2 - Thermal Science T1 - Laser doppler velocimetry and confined flows EP - S836 IS - Suppl. 3 SP - S825 VL - 21 DO - 10.2298/TSCI160720278I ER -
@article{ author = "Ilić, Jelena and Ristić, Slavica and Srećković, Milesa", year = "2017", abstract = "Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure.", publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd", journal = "Thermal Science", title = "Laser doppler velocimetry and confined flows", pages = "S836-S825", number = "Suppl. 3", volume = "21", doi = "10.2298/TSCI160720278I" }
Ilić, J., Ristić, S.,& Srećković, M.. (2017). Laser doppler velocimetry and confined flows. in Thermal Science Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 21(Suppl. 3), S825-S836. https://doi.org/10.2298/TSCI160720278I
Ilić J, Ristić S, Srećković M. Laser doppler velocimetry and confined flows. in Thermal Science. 2017;21(Suppl. 3):S825-S836. doi:10.2298/TSCI160720278I .
Ilić, Jelena, Ristić, Slavica, Srećković, Milesa, "Laser doppler velocimetry and confined flows" in Thermal Science, 21, no. Suppl. 3 (2017):S825-S836, https://doi.org/10.2298/TSCI160720278I . .