ID 177

Instability of the elliptic liquid jet

 

Abstract:

The breakup and instability of viscoelastic elliptic jets are of great importance both for academic interests and practical applications, such as ink-jet printing, fuel injection spraying, and fiber spinning. In the present article, the instable behavior of incompressible elliptical viscoelastic jets is investigated. In order to be more precise in the theory, temporal dispersion equation is derived on the base of the one-dimensional closure models (“One-dimensional closure models for three-dimensional incompressible viscoelastic free jets: von Karman flow geometry and elliptical cross-section”, Bechtel S.E & Forest M.G, Journal of Fluid Mechanics, 1988, 196(196):241-262) rather than the one dimensional Cosserat equations (Axis-switching and breakup of low-speed elliptic liquid jets, Amini G & Dolatabadi A, International Journal of Multiphase Flow, 2012, 42:96-103) which is employed by most of the other researchers. Moreover, the effect of the jet viscoelasticity for its instability is considered. According to the temporal dispersion equation, the article reveal the phenomenon of the axis-switching for elliptic jets. Besides, the variation of growth rate under the effect of perturbation for viscoelastic jets is demonstrated. The paper figures out the role of the surface tense, viscoelasticity and geometrical shape in the jet instability.