Planar liquid volume fraction measurements in air-blast sprays using SLIPI technique with numerical corrections
A methodology to improve the accuracy of liquid volume fraction measurement in a dense spray is presented. A combination of experimental technique, structured laser illumination and planar imaging (SLIPI) and numerical corrections is used to overcome losses in conventional planar laser-induced fluorescence (PLIF) imaging. A quantitative distribution of liquid volume fraction in a plane is obtained using corrected SLIPI–PLIF signal and PDIA (particle/droplet imaging analysis) technique. The methodology is applied to air-blast sprays for GLRs (gas to liquid mass ratio) 1, 2.5 and 4. The effect of multiple scattering is significantly high in the conventional PLIF signal imaging. A hollow cone spray geometry is observed at a GLR of 1 using the improved imaging technique. An increase in GLR from 1 to 4 leads to uniform distribution of liquid in a spray plane. A significant contribution of multiple scattering (\(\sim\) 62%) is observed in the conventional PLIF signal at GLR 4 along the axis of the spray. The symmetry in the SLIPI–PLIF signal is restored using the numerical corrections. The liquid volume fraction measurements from SLIPI–PLIF technique are further improved with the numerical corrections.
Funding was provided by SERB-DST India (Grant no. SB/S3/MMER/0028/2013).
- 4.C.T. Brown, V.G. McDonnell, D.G. Talley, Accounting for laser extinction, signal attenuation, and secondary emission while performing optical patternation in a single plane. In Fifteenth Annual Conference on Liquid Atomization and Spray Systems, Madison, WI, USA (2002)Google Scholar
- 13.E. Kristensson, Structured Laser illumination planar imaging: SLIPI applications for spray diagnostics. Ph.D. Thesis, Lund University, Lund, 2012Google Scholar
- 22.Y.N. Mishra, Droplet size, concentration, and temperature mapping in sprays using SLIPI-based techniques, Ph.D. Thesis, Lund University, Lund (2018)Google Scholar
- 28.J. Sjöholm, C. Chartier, E. Kristensson, E. Berrocal, Y. Gallo, M. Richter, Ö. Andersson, M. Aldén, B. Johansson, Quantitative in-cylinder fuel measurements in a heavy duty diesel engine using structured laser illumination planar imaging (SLIPI). In COMODIA 2012, MD2, vol 3 (2012)Google Scholar
- 30.D. Talley, J. Verdieck, S. Lee, V. McDonell, G. Samuelsen. Accounting for laser sheet extinction in applying PLLIF to sprays. In 34th Aerospace Sciences Meeting and Exhibit, p. 469 (1996). https://doi.org/10.2514/6.1996-469
- 32.P. Walker, W.H. Tarn, CRC Handbook of Metal Etchants (CRC Press, Boca Raton, 1990)Google Scholar