Abstract
The main purpose of the present paper was to apply the Laser Doppler Anemometry (LDA) technique to measure turbulent liquid flow in a Kenics static mixer. The LDA set-up was a one-channel backscatter system with argon-ion laser. Measurements in the static mixer were carried out for three values of the Reynolds number: 5000, 10000, and 18000. Water was used as the process liquid. Values of the axial and tangential components of the local, mean, and root mean square velocities were measured inside the static mixer. It was observed that the shape of the velocity profile depends strongly on the Reynolds number, Re, as well as on the axial, h, and radial, α, position of the measurement point. Strong dependence of the velocity fluctuations on the Reynolds number was found in the investigated range of Re and the measurement point position. Furthermore, one-dimensional energy spectra of the velocity fluctuations were also obtained by means of the Fast Fourier Transform. Fluctuation spectra of the axial and tangential velocities provided information about the energy density of velocity fluctuations in the observed range of Reynolds numbers. A study of the energy spectra led to the conclusion that the energy density increases with the increasing radial distance from the mixer walls at constant values of h, Re, and α. Minor variations in the mean value of the energy density, E, were observed together with variations of the measurement point angular position, α. In addition, it was observed that an increase of the Reynolds number causes significant increase of the power spectral density.
Similar content being viewed by others
References
Adamiak, I., & Jaworski, Z. (2001). An experimental investigations of non-Newtonian liquid flow in a static Kenics mixer. Chemical and Process Engineering, 22(3B), 175–180. (in Polish)
Adamiak, I., & Jaworski, Z. (2004). A non-Newtonian fluid turbulent flow in the kenics static mixer. Chemical and Process Engineering, 25, 535–541. (in Polish)
Albrecht, H. E., Borys, M., Damaschke, N., & Tropea, C. (2003). Laser Doppler and phase Doppler measurement techniques. Berlin, Germany: Springer.
Baldi, S., & Yianneskis, M. (2004). On the quantification of energy dissipation in the impeller stream of a stirred vessel from fluctuating velocity gradient measurements. Chemical Engineering Science, 59, 2659–2671. DOI: 10.1016/j.ces.2004.03. 021.
Barrué, H., Karoui, A., Le Sauze, N., Costes, J., & Illy, F. (2001). Comparison of aerodynamics and mixing mechanisms of three mixers: Oxynator™ gas-gas mixer, KMA and SMI static mixers. Chemical Engineering Journal, 84, 343–354. DOI: 10.1016/s1385-8947(01)00128-0.
Baudou, C., Xuereb, C., Costes, J., & Bertrand, J. (2000). Laser Doppler measurements of turbulent parameters in different multiple-propeller systems. Chemical Engineering & Technology, 23, 257–266. DOI: 10.1002/(SICI)1521-4125(200003)23:3<257::AID-CEAT257>3.0.CO;2-4.
Bell, W. A. (1986). Spectral analysis of laser velocimeter data with the slotted correlation method. In Proceedings of the AIAA/ASME 4th Fluid Dynamics, Plasma Dynamics and Lasers Conference, May 12–14, 1986 (AIAA paper 86-1102). Atlanta, GA, USA.
Benedict, L. H., Nobach, H., & Tropea, C. (2000). Estimation of turbulent velocity spectra from laser Doppler data. Measurement Science and Technology, 11, 1089–1104. DOI: 10.1088/0957-0233/11/8/301.
Crowe, C., Sommerfeld, M., & Tsuji, Y. (1998). Multiphase flows with droplets and particles. Boca Raton, FL, USA: CRC Press.
Darelius, A., Rasmuson, A., Niklasson Björn, I., & Folestad, S. (2007). LDA measurements of near wall powder velocities in a high shear mixer. Chemical Engineering Science, 62, 5770–5776. DOI: 10.1016/j.ces.2007.06.015.
Deshpande, S. S., Sathe, M. J., & Joshi, J. B. (2009). Evaluation of local turbulent energy dissipation rate using PIV in jet loop reactor. Industrial & Engineering Chemistry Research, 48, 5046–5057. DOI: 10.1021/ie8007924.
Forrest, S., Bridgwater, J., Mort, P. R., Litster, J., & Parker, D. J. (2003). Flow patterns in granulating systems. Powder Technology, 130, 91–96. DOI: 10.1016/s0032-5910(02)00232-2.
Goldstein, R. J. (1996). Fluid mechanics measurements (2nd ed.). Philadelphia, PA, USA: Taylor & Francis.
Habchi, C, Lemenand, T, Della Valle, D., & Peerhossaini, H. (2010). Turbulent mixing and residence time distribution in novel multifunctional heat exchangers-reactors. Chemical Engineering and Processing, 49, 1066–1075. DOI: 10.1016/j.cep.2010.08.007.
Hobbs, D. M., & Muzzio, F. J. (1998). Reynolds number effects on laminar mixing in the Kenics static mixer. Chemical Engineering Journal, 70, 93–104. DOI: 10.1016/s0923-0467(98)00065-7.
Ibsen, C. H., Solberg, T., Hjertager, B. H., & Johnsson, F. (2002). Laser Doppler anemometry measurements in a circulating fluidized bed of metal particles. Experimental Thermal and Fluid Science, 26, 851–859. DOI: 10.1016/s0894-1777(02)00196-6.
Jaffer, S. A., & Wood, P. E. (1998). Quantification of laminar mixing in the Kenics static mixer: An experimental study. The Canadian Journal of Chemical Engineering, 76, 516–521. DOI: 10.1002/cjce.5450760323.
James, R. N., Babcock, W. R., & Seifert, H. S. (1968). A laser-Doppler technique for the measurement of particle velocity. AIAA Journal, 6(1), 160–162.
Kaci, H. M., Lemenand, T., Della Valle, D., & Peerhossaini, H. (2009). Effects of embedded streamwise vorticity on turbulent mixing. Chemical Engineering and Processing: Process Intensification, 48, 1457–1474. DOI: 10.1016/j.cep.2009.08.002.
Karoui, A., LeSauze, N., Costes, J., & Bertrand, J. (1997). Experimental and numerical study of flow at the outlet of Sulzer SMV static mixers. Récents Progr`es en Génie des Procédés, 11(51), 323–330.
Kroon, P. S., Schuitmaker, A., Jonker, H. J. J., Tummers, M. J., Hensen, A., & Bosveld, F. C. (2010). An evaluation by laser Doppler anemometry of the correction algorithm based on Kaimal co-spectra for high frequency losses of EC flux measurements of CH4 and N2O. Agricultural and Forest Meteorology, 150, 794–805. DOI: 10.1016/j.agrformet.2009.08.009.
Kumara, W. A. S., Elseth, G., Halvorsen, B. M., & Melaaen, M. C. (2010). Comparison of Particle Image Velocimetry and Laser Doppler Anemometry measurement methods applied to the oil-water flow in horizontal pipe. Flow Measurement and Instrumentation, 21, 105–117. DOI: 10.1016/j.flowmeasinst.2010.01.005.
Laurenzi, F., Coroneo, M., Montante, G., Paglianti, A., & Magelli, F. (2009). Experimental and computational analysis of immiscible liquid-liquid dispersions in stirred vessels. Chemical Engineering Research and Design, 87, 507–514. DOI: 10.1016/j.cherd.2008.12.007.
Leitner, M., Wünsch, O., & Böhme, G. (2003). Dreidimensionale LDV und FEM zur Strömungsanalyse in statischen Mischelementen. Forschung im Ingenieurwesen, 68(1), 39–50. DOI: 10.1007/s10010-003-0109-4. (in German)
Lu, Y., Glass, D. H., & Easson, W. J. (2009). An investigation of particle behavior in gas-solid horizontal pipe flow by an extended LDA technique. Fuel, 88, 2520–2531. DOI: 10.1016/j.fuel.2009.02.038.
Lui, S. W., Meneveau, C., & Katz, J. (1994). On the properties of similarity subgrid-scale models as deduced from measurements in a turbulent jet. Journal of Fluid Mechanics, 275, 83–119. DOI: 10.1017/s0022112094002296.
Mokrani, A., Castelain, C., & Peerhossaini, H. (2009). Experimental study of the influence of the rows of vortex generators on turbulence structure in a tube. Chemical Engineering and Processing: Process Intensification, 48, 659–671. DOI: 10.1016/j.cep.2008.07.009.
Paál, G., Angster, J., Garen, W., & Miklós, A. (2006). A combined LDA and flow-visualization study on flue organ pipes. Experiments in Fluids, 40, 825–835. DOI: 10.1007/s00348-006-0114-0.
Paul, E. L., Atiemo-Obeng, V., & Kresta, S. M. (2003). Handbook of industrial mixing: science and practice. Hoboken, NJ, USA: Wiley.
Peryt-Stawiarska, S., & Jaworski, Z. (2007). Large eddy simulations of the Newtonian fluid flow through a Kenics static mixer. Chemical and Process Engineering, 28, 435–444.
Peryt-Stawiarska, S., & Jaworski, Z. (2008). Fluctuations of the non-Newtonian fluid flow in a Kenics static mixer: An experimental study. Polish Journal of Chemical Technology, 10(3), 35–37. DOI: 10.2478/v10026-008-0033-3.
Pope, S. B. (2000). Turbulent flows. Cambridge, UK: Cambridge University Press.
Song, H. S., & Han, S. P. (2005). A general correlation for pressure drop in a Kenics static mixer. Chemical Engineering Science, 60, 5696–5704. DOI: 10.1016/j.ces.2005.04.084.
Szalai, E. S., & Muzzio, F. J. (2003). Fundamental approach to the design and optimization of static mixers. AIChE Journal, 49, 2687–2699. DOI: 10.1002/aic.690491103.
Tran, A. L. H., Litster, J. D., Seville, J. P. K., Ingram, A., & Fan, X. F. (2006). Dry and cohesive powders in vertical axis high shear mixers using positron emission particle tracking (PEPT). In Proceedings of the 5th World Congress on Particle Technology, April 23–27, 2006. Orlando, FL, USA: The American Institute of Chemical Engineers.
Tropea, C., Yarin, A. L., & Foss, J. F. (Eds.) (2007). Springer Handbook of experimental fluid mechanics. Berlin, Germany: Springer.
van Wageningen, W. F. C., Mudde, R. F., & van den Akker, H. E. A. (2003). Numerical investigation into mixing of particle-laden flows in a Kenics static mixer. In Proceedings of the 11th European Conference Mixing (pp. 137–144), October 14–17, 2003. Bamberg, Germany.
van Wageningen, W. F. C., Kandhai, D., Mudde, R. F., & van den Akker, H. E. A. (2004). Dynamic flow in a Kenics static mixer: An assessment of various CFD methods. AIChE Journal, 50, 1684–1696. DOI: 10.1002/aic.10178.
Wiklund, J. A., Stading, M., Pettersson, A. J., & Rasmuson, A. (2006). A comparative study of UVP and LDA techniques for pulp suspensions in pipe flow. AIChE Journal, 52, 484–495. DOI: 10.1002/aic.10653.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Rights and permissions
About this article
Cite this article
Murasiewicz, H., Jaworski, Z. Investigation of turbulent flow field in a Kenics static mixer by Laser Doppler Anemometry. Chem. Pap. 67, 1188–1200 (2013). https://doi.org/10.2478/s11696-013-0375-z
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.2478/s11696-013-0375-z