JET SWELLING OF CONCENTRATED SILICON OIL-IN-WATER EMULSIONS

Jet swelling is shown to exist when a concentrated oil-in-water emulsi on is ejected from a capillary tube into a stagnant fluid. The jet swe lls up to ten times the diameter of the capillary tube depending on th e shear rate in the tube and the density difference between the ejecte d and the stagnant fluid. The relative jet swelling increases with sil icone oil concentration, decreases in silicone oil viscosity, decrease s in tube diameter, and decreases in tube length. The diameter ratio ( jet/tube) grows as the 1/3 power of the wall shear stress in the capil lary tube. The analogy between the swelling behavior of these emulsion s and that observed in dilute and semidilute polymer solutions is disc ussed.