An opposed jets device for studying the breakup of dispersed liquid drops

• Published in: Chemical engineering science Vol. 48; no. 2; pp. 255 - 265
• Main Authors: Janssen, J.M.H., Peters, G.W.M., Meijer, H.E.H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1993; Elsevier
• Subjects: Applied sciences; Chemical engineering; Dispersive mixing; drop breakup; elongational flow; Exact sciences and technology; Mixing; opposed jets; opposed jets; elongational flow; drop breakup; Dispersive mixing; Mixing; Opposed jet; Rupture; Doppler laser anemometer; Theoretical study; Velocity distribution; Experimental study; Liquid liquid; Elongational flow; Modeling; Dispersion; Drop
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/0009-2509(93)80013-G

Many studies on the dispersion of one liquid in another concentrate on the deformation and breakup of a single drop in a well defined flow. This paper describes the design of a device, which has not yet been used in this field. The concept makes use of the stagnation flow of two opposed jets in a closed circuit. A numerical study results in channel geometries for plane hyperbolic flow, which is purely extensional, and for a flow type which combines extension and vorticity. A device with dimensions of several centimeters suffices to study deformation of a 1 mm drop. Experiments show that the model for plane hyperbolic flow is obeyed in a large region around the stagnation point. A control system is developed to position the deforming drop steadily at the, principally unstable, stagnation point. A control cycle consists of determination of the drop position and calculation and realization of the required flow adjustment. In the present experimental setup the deformation of a drop in 2-dimensional elongational flow can be studied via video recording. The setup chosen not only allows for model lqiuids but can be adjusted to allow for polymer melts as well.