To validate the drag force model and to learn more about the fluidization behavior of non-spherical particles the pressure drop, particle height and orientation distributions were analyzed. Simulations were performed with a coupled DEM-CFD approach, which involves a drag force model that realizes for the particle shape and orientation. Presence of a mixing zone was also confirmed by the CFD model and simulated particle phase volume fraction distribution qualitatively agreed with the experimental visualisations.Ī laboratory scale fluidized bed was examined experimentally and numerically involving differently sized wooden Geldart-D particle shapes. The model predicted expanded bed height agreed with experimental measurements within ☖% deviation. Finally, a two-dimensional (2D) Eulerian-Eulerian (E-E) model incorporating the kinetic theory of granular flow (KTGF) was used to quantify the binary system hydrodynamics. The expanded bed height of the binary mixture was not entirely additive of its corresponding mono-component bed heights and both positive and negative deviations were observed. The bed expansion ratio was noted to decrease with increasing solid mass ratio however it increased with increase in the fluidising velocity ratio following a reasonable power law trend. For lower diameter ratio cases, a relatively lager mixing zone height was observed which increased with increasing liquid superficial velocity. A slight decrease in the mixing zone height was noted with increasing liquid superficial velocity. A small mixing zone spanning approximately two particle diameters thick was observed to exist even in a completely segregated SLFB for higher diameter ratio cases. In a completely segregated SLFB, the bottom monosized layer exhibited a negative deviation ∼23% whereas a positive deviation ∼25% was found in the top monosized layer when compared with the corresponding pure monosized system. In the expanded bed, both segregated and intermixed zones were observed depending on the different particle diameter combinations. Experiments were performed comprising equal density (2230 kg m⁻³) spherical glass beads particles of diameter 3, 5 and 8 mm and water as fluidising medium with different particle mass ratios varying from 0.17 to 6.0. This study reports the effect of particle mass compositions on the bed expansion behaviour of a binary solid liquid fluidised bed (SLFB) system. For validation Octave Levenspiel’s equations for both pressure drop and minimum fluidisation velocity were applied, showing good agreement with the experimental work in terms of using the liquid as a working fluid. The fluidisation state showed a lower pressure drop than the fixed state, reducing power consumption. It was observed that the minimum fluidisation did not change with changes in the initial height, though pressure drop increased with the increase in initial height and both pressure drop and minimum fluidisation velocity increased with increase in temperature. The pressure data were recorded using the LabVIEW program and an Arduino.Ī comparison was made between a stationary (fixed) and fluidised bed by measuring the pressure drop in each case via pressure sensors at the same flow rate, temperature level, and initial height of bed.

The pressure sensors were located 10 cm apart, beginning at the bed mesh holder. In order to study the effect of changing the properties of water, a heater with a temperature controller was used to control the temperature of water for each experimental run at one of two levels (20 and 30 ☌) to examine any changes occurring in terms of values of pressure drop at minimum fluidisation velocity.Īll experimental runs were carried out in a cylindrical Perspex column with a 5 cm inside diameter, 5 mm wall thickness, and 100 cm length six pressure sensors of transducer type (analogue) were fixed on wall of the column and at bed height in order to measure the pressure the pressure differences between any two points were thus calculable. Glass beads with different sizes (6 and 8 mm d p ) with density 2, 550 kg/m ³ were used, with distilled water as the liquid. This research investigated the effect of different initial heights of packed bed on pressure drop and minimum fluidisation velocity in packing bed columns.

Will drop power consumption