23-07-2012, 02:43 PM
Dynamics of Particulate systems
Dynamics of Particulate systems.ppt (Size: 9.36 MB / Downloads: 245)
) Electrohydrodynamic atomization fabrication of pharmaceutical particles, (2) bubble motion in Taylor vortex, (3) vibrated granular bed system, (4) pneumatic transport of granular material.
Measurement techniques used in the study of such systems include Electrical Capacitance Tomography (ECT), Particle Image Velocimetry (PIV) and Phase Doppler Particle Analyzer (PDPA).
Summary for Horizontal & Vertical Conveying
Using single plane data - time averaged particle concentration.
Using twin plane cross correlation – pattern velocity.
Single plane particle concentration data vs time data
(a) Homogeneous is not homogeneous.
(b) Moving dunes and eroding dunes with multiple characteristic peaks in the lower frequency region.
(c ) Plug flow with a single largest peak at near zero frequency.
Cross sectional variation of time averaged density distribution in different flow regimes.
Results and Discussion
The solid concentration profiles in horizontal pneumatic conveying show quantitatively the effects of gravitational settling which results in higher solid concentrations along the bottom wall of the pipe
As before, the solid concentration profiles are quantitatively similar for different gas velocities used