Linear analysis of the temporal instability of axisymmetrical non-Newtonian liquid jets

As gel propellants are increasingly used in rocket engines, non-Newtonian liquid atomization has emerged as a research subject of great interest. This paper addresses the atomization of flat sheets of aqueous xanthan gum solution, which are formed from two jets ejected from impinging injectors. Based on the experimental photos, it has been found that gel liquid sheets do not break up directly into droplets that can be characterized as spheres with Sauter mean diameter; instead, a mass of ligaments is observed. Therefore, this paper will introduce fractal dimension as a new parameter, related to the quality of atomization under these experimental conditions; and a power-law correlation between fractal dimension and Reynolds number of liquid jets has been achieved.

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Temporal instability of charged viscoelastic liquid jets under an axial electric field

European Journal of Mechanics - B/Fluids ◽

10.1016/j.euromechflu.2017.03.007 ◽

2017 ◽

Vol 66 ◽

pp. 60-70 ◽

Cited By ~ 17

Author(s):

Luo Xie ◽

Li-jun Yang ◽

Li-zi Qin ◽

Qing-fei Fu

Keyword(s):

Electric Field ◽

Viscoelastic Liquid ◽

Liquid Jets ◽

Axial Electric Field ◽

Temporal Instability

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A Numerical Study on Flow Characteristics of 2D Vertical Liquid Jet Striking a Horizontal Surface

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 3 ◽

10.1115/esda2010-25136 ◽

2010 ◽

Author(s):

M. Kimiaghalam ◽

M. Passandideh-Fard

Keyword(s):

Reynolds Number ◽

Hydraulic Jump ◽

Numerical Study ◽

Flow Characteristics ◽

Newtonian Liquid ◽

Liquid Jets ◽

Liquid Jet ◽

Moderate Reynolds Number ◽

Different Types ◽

Newtonian Liquids

We studied numerically impingement of vertical liquid jets of moderate Reynolds number for both Newtonian and non-Newtonian liquids to clarify the structure formation of circular hydraulic jump and the phenomenon of jet buckling. First, we have studied the hydraulic jump characteristics and governing parameters for a laminar water jet. Moreover, different types of hydraulic jump have been investigated by varying the height of a circular wall around the bed in flow downstream. The results show that a circular hydraulic jump has two kinds of steady states which can be reached by changing wall height. Next, we studied the impingement of a non-Newtonian liquid jet on a solid surface. In this case, we observe that instead of having a significant hydraulic jump, jet buckling phenomenon happens. The results were used in order to achieve a better understanding of the jet buckling phenomenon and the conditions in which this phenomenon happens.

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