Interface Location in Single Phase Stirred Tanks

In this work, study the location of interface in a stirred vessel with Rushton impeller by computational fluid dynamic was presented. To modeling rotating the impeller, sliding mesh (SM) technique was used and standard k-ε model was selected for turbulence closure. Mean tangential, radial and axial velocities and also turbulent kinetic energy (k) and turbulent dissipation rate (ε) in various points of tank was investigated. Results show sensitivity of system to location of interface and radius of 7 to 10cm for interface in the vessel with existence characteristics cause to increase the accuracy of simulation.





References:
[1] Ranade VV, Bourne JR, Joshi JB., 1991, Fluid mechanics and blending
in agitated tanks. Chem Eng Sci (46), 1883–1893.
[2] Ng,K., Fentiman, N.J., Lee,K.C. and Yianneskis, M., 1998, Assessment
of sliding mesh CFD predictions and LDA measurements of the flow in
a tank stirred by a Rushton impeller, Trans IChemE, Part A, Chem Eng
Res Des, 76(A8), 737–747.
[3] Murthy JY, Mathur SR., 1994, CFD simulation of flows in stirred tank
reactors using a sliding mesh technique. IChemE Symp Ser ;136:341–8.
[4] Luo JY, Issa RI, Gosman D., 1994, Prediction of impeller induced flows
in mixing vessels using multiple frames of reference. IChemE Symp Ser
;136:549–56.
[5] Mostek M, Kukukova A, Jahoda M, Machon V., 2005, Comparison of
different[techniques for modelling of flow field and homogenization in
stirred vessels. Chem Pap;59 (Part 6):380–5.
[6] Jaworski Z, Dudczak J., 1998, CFD modelling of turbulent
macromixing in stirred tanks. Effect of the probe size and number on
mixing indices. Comput Chem Eng; 22 (Suppl.1): 293–8.
[7] Van’t Riet, K., Smith, J.M., 1973, The behaviours of gas-liquid
mixtures near Rushton turbine blades, Chem. Eng.Sci. (28), 1031-1037.
[8] Van’t Riet, K., Smith, J.M., 1975, The trailing vortex system produced
by Rushton turbine agitators, Chem. Eng.Sci. (30), 1093-1105.
[9] J.Y. Oldshue, 1983, Fluid Mixing Technology, McGraw Hill, New York
[10] K.C. Lee, M Yianneskis, 1998, Turbulence properties of the impeller
stream of a Rushton turbine, Am. Inst. Chem. Eng. J. 44, 13-24.
[11] F.Guillard, C, Tragardh, 2003, Mixing in industrial Rushton turbine
agitated reactors under aerated conditions, Chem, Eng. Process. 421,
375-386.
[12] Wu,H., Patterson,G.K., 1989, Laser-Doppler Measurements of Turblent-
Flow Parameters in a Stirrred Mixer, Chemical Engineering Science.,44,
(10).2207-2221.