An experimental study of the hydrodynamics of mutliphase flow in fluidized beds
Fluidized bed reactors have been widely used as a gasifier in coal gasification processes to convert coal into other forms of energy. At this stage, full fluidization is required to attain the best thermochemical reaction within the fluid-solid mixture. This can only be achieved if the fluid is maintained between minimum fluidization and terminal velocities. To better understand the hydrodynamics of multiphase flow, a fluidized bed was designed and constructed to carry out the investigation. Compressed air and 1-mm glass beads were used to determine gas minimum fluidization and terminal velocities at three different particle concentrations. The solids were enclosed in a 1.25-in inner diameter bed measuring 1 cm, 3 cm and 5 cm for each experimental setup. Additionally, pressure measurements at minimum fluidization were compared with theoretical values to corroborate the experimental results. In addition to gas flow rate measurements, the particles velocity at fluid terminal velocities was measured with two different techniques: laser doppler anemometer (LDA) and particle image velocimetry in Matlab (MatPIV) software. The first measured individual particle velocity in the axial direction, and the second measured the velocity of the particles as a whole. Lastly, video sequences of the fluidized bed are presented to provide a visual reference of the particles behavior at different fluidization stages.
Alternative Energy|Mechanical engineering
Vargas Duarte, Gerardo, "An experimental study of the hydrodynamics of mutliphase flow in fluidized beds" (2009). ETD Collection for University of Texas, El Paso. AAI1473897.