Ultrasonic fragmentation of agglomerate powders

A theory for ultrasonic fragmentation of agglomerate particles suspended in liquids is presented. Imploding cavitation bubbles rupture the agglomerates. An expression for the fragmentation rate as a function of ultraosnic power and agglomerate size is derived. A sectional model for fragmentation is used to simulate the evolution of the particle size distribution of silica and titania powders suspended in water. The fragmentation rate expression is evaluated by comparing simulated with experimental size distributions at the self-preserving limit. The required time and energy for particle size reduction is calculated as a function of ultrasonic power input.

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