Experimental Investigation of Breakup Characteristics of Elliptical, Rectangular and Circular Water Jets

علوم کاربردی و محاسباتی در مکانیک

Article 1, Volume 30, Issue 1 - Serial Number 19, June 2018, Pages 1-16   

Document Type: Original Article

DOI: 10.22067/fum-mech.v30i1.68226

Authors

Amin Jaberi^* ; Mehran Tadjfar; Armin Sheidani

Amirkabir University of Technology

Abstract

In this study, the instabilities of elliptical, rectangular and circular water jets were experimentally investigated. Shadowgraph technique was employed to capture the jet column status instantaneously. Jet parameters such as disintegration length and axis switching wavelength were quantitatively studied. The results showed that due to the similar characteristics of rectangular and elliptical jets, their breakup length in the second wind-induced regime is nearly equal, while the breakup length of circular jet is perceptibly shorter. Both rectangular and elliptical jets are affected by aerodynamic forces sooner and thus enter the first wind induced regime at lower velocities. Furthermore, it was revealed that the axis switching wavelength is not dependent upon the jet geometry at low Weber numbers and remains equal for both elliptical and rectangular jets. However, at high Weber numbers, the axis switching wavelength of rectangular jet become larger than the elliptical one. Based on the obtained results, a semi-empirical relation was proposed to predict the axis switching wavelength of rectangular and elliptical jets.

Keywords

Water jet breakup; axis switching phenomenon; elliptical jet; rectangular jet; multiphase flows

Supplementary Files

EA-1-Tadjfar.pdf

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