Particle Discharge Characteristics from the Nozzle of a Thin Tube Immersed in Liquid Subjected to Ultrasonic Wave Force [Translated]^†

Abstract

A wet micro-feeder that utilizes ultrasonic wave force was designed and constructed to feed small particles into a container of wet particulate materials. The particle discharge characteristics from a nozzle with the inside diameter D_n were investigated using spherical and irregular particles of 80 to 180mm in diameter, d_p.
As a result, the critical ratio for particle blockage of the present feeder, (D_n/d_p)_c≒3.0, was found to be smaller than the values obtained previously (>4 ∼ 5) in the gravitational field for dry powders. The present feeder was able to achieve stable and continuous discharge of small amounts of particles. Multiple regression analysis proved that the discharge rate of particles, i.e. the number of particles discharged from the nozzle per unit of time, N̄, depended on D_n, d_p, the applied voltage V₀, and the median value of the particle shape index (surface roughness), y₅₀, and that N̄ was proportional to D_n^2.29. Therefore, N̄ could be controlled by V₀ and D_n for given particles.

^† This report was originally printed in J. Soc. Powder Technology, Japan, 38(9), 617-625 (2001) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Powder Technology, Japan.