Prevention of particle deposition on bubble surface at angles

Prevention of Particle Deposition on Bubble Surface at Angles 0  

DUE TO Joint Action of Particle Reflection from a Bubble Surface and Centrifugal Forces 

Inertia forces manifest themselves in at least in three effects 1 - shift of particles trajectories away from the liquid stream-lines from the bubble (Section 10.1) 2 - deformation of the bubble surface by a particle at the instant of impact (cf. Section 11.1) 3 - prevention of particle deposition on some parts of the bubble surface due to centrifugal forces (cf Section 11.3). In the present section these effects are considered simultaneously (Dukhin et al. 1986), although some restrictions are imposed on the properties of the bubbles and the particles. 

For this investigation, the bubbles are assumed to be spherical and their diameters are taken to be of the order of millimetre having a non-retarded surface (this is necessary for the use the theory developed in Section 11.3, which enables to describe the hydrodynamic field of bubble by a potential one). In addition, only spherical particles with smooth surface are considered (this makes it possible to use the results of the consideration of film thinning at the inertia impact of a particle on bubble surface from Section 11.2 and experimented data). Upper and lower limits of particle size are assumed, the necessity of which will be explained later. 

To trace the final location of a particle, it is important to know how the conditions of an inertia impact change as a function of its localisation on the bubble surface. This dependence is clear in experimental studies by Schulze Gottschalk (1981). Their observations have shown that two zones exist on a bubble surface. In the first zone adjacent to the bubble pole with an angle 

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