Ligament break

Small satellite droplets, which are produced along with the uniform size larger droplets when ligaments break, can easily be removed. Droplet sizes from 15 microns to 3 mm. have been produced. The proportion and size of satellite droplets increase with increased liquid flow rates until a flow is reached where separation is no longer possible. Liquid viscosity plays a negligible role. 

Dombrowski [12] has shown that symmetrical waves are mainly responsible for ligaments break down. Weber et al. [26] have analyzed these waves and assuming that here their results can be applied, we use equation 1.41 to estimate breakup wavenumber ... 

Liquid-Sheet Breakup The basic principle of most hydraulic atomizers is to form a thin sheet that breaks via a variety of mechanisms to form ligaments of liquid which in turn yield chains of droplets. See Fig. 14-86. 

Ligament diameter depends mainly on the film thickness, and thus thinner liquid films break down into smaller droplets. Rizk and Lefebvre 9X observed SMD oc ts0A, where SMD is the Sauter mean diameter of droplets. York et al.[255 and Dombrowski and... 

A droplet is initially elongated to a long cylindrical thread or ligament of cigar shape, and then breaks up into smaller droplets. 

Break-up of the jet occurs as follows. Ligaments of liquid are tom off, which collapse to form drops. These may be subsequently blown out into films, which in turn further collapse to give a fine spray. Generally, this spray has a small cone angle and is capable of penetrating far greater distances than the pressure nozzle. Small atomisers of this type have been used in spray-drying units of low capacities. 

Ligament Breakup. Columns of liquid break up in air owing to the development of oscillations which increase in amplitude until this exceeds... 

Fig. 4.12 Crack growth along grain boundaries in AD96. Because of the relatively narrow separation between grains, cavities grow into cracks once they start to propagate. Note that the crack is not completely open, but is joined across its faces by unbroken ligaments (L) that must also break for propagation to proceed. From Jakus et a/.105...

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