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Title: DEM modeling of fine powder convection in a continuous vibrating bed reactor
Continuous vibrating spatial particle ALD reactors were developed to achieve high powder throughput while minimizing reactor footprint. Unlike fluidized bed reactors, continuous vibrating spatial particle ALD reactors operate below fluidization, using linear vibration to convey particles through alternating regions of precursor gas. Fine powder convection in these vibrating bed reactors is still not well understood, so cohesive discrete element- method (DEM) simulations were performed to investigate the solids flow behavior. Using a Fast Fourier Transform(FFT) algorithm, we constructed a sum-of-sines model for the reactor kinematics based on accelerometer data. Accelerometer results and DEM simulations revealed the role of high-frequency excitations and need for backsliding and sticking avoidance in horizontal conveyors at low-g accelerations. From these observations, we propose a novel sawtooth excitation to enable convection of cohesive fine powders at low flow velocities. The model results were compared to data from an in-house continuous vibrating spatial particle ALD reactor.  more » « less
Award ID(s):
1852824
PAR ID:
10231662
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Powder technology
Volume:
386
ISSN:
0032-5910
Page Range / eLocation ID:
209-220
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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