Transportation of Cereal Grains by Vibratory Air-Slide Conveyor

Abstract

In order to find whether a vibratory air-slide mechanism is applicable as a so called process conveyor, the authors constructed the small sized apparatus.
The grain particles on the trough were pseudo-fluidized and transported by means of aeration and vibration.
Materials tested were paddy and brown rice, and flow properties obtained were as follows:
(1) The grain particles of paddy and brown rice were made pseudo-fluidized and transported on the trough at an apparent air velocity u_a in less than a half the minimum fluidization velocity u_mf under the conditions of vibration intensity factor Kv=1.5-3.0 and trough angle θ'=0°-6°.
(2) Grain rate G's (t/h) gradually increased as an increase of Kv or θ', and approached a constant value under the condition of Kv≥2.5 and θ'≥4°.
(3) Assumed only a gravity get the fluidized bed slipped down on the trough, the velocity at any position on the trough would be shown as
U_s=√2gl[sinθ-μ_dis{cosθ+(h/b)secθ}]
The experimental data calculated by the above equation shows the following relation,
μ_dis=kθ
where k is constant and 0.799 for paddy and 0.870 for brown rice.