Effects of the Charge-Dipole Interaction on the Coagulation of Fractal Aggregates

Lorin Swint Matthews; T. W. Hyde

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Effects of the Charge-Dipole Interaction on the Coagulation of Fractal Aggregates

Lorin Swint Matthews·T. W. Hyde

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Abstract

A numerical model with broad applications to complex (dusty) plasmas is presented. The self-consistent N-body code allows simulation of the coagulation of fractal aggregates, including the charge-dipole interaction of the clusters due to the spatial arrangement of charge on the aggregate. It is shown that not only does a population of oppositely charged particles increase the coagulation rate, the inclusion of the charge-dipole interaction of the aggregates as well as the electric dipole potential of the dust ensemble decreases the gelation time by a factor of up to twenty. It is further shown that these interactions can also stimulate the onset of gelation, or "runaway growth," even in a population of particles charged to a monopotential where previously it was believed that like-charged grains would inhibit coagulation. Gelation is observed to occur due to the formation of high-mass aggregates with fractal dimensions greater than two which act as seeds for runaway growth.

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Lorin Swint Matthews, T. W. Hyde. 2004-01-22. Effects of the Charge-Dipole Interaction on the Coagulation of Fractal Aggregates. https://arxiv.org/abs/physics/0401115

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