An experimental study on flow dynamics through packed beds

In this thesis, a systematic experimental study on flow dynamics throughpacked beds having different geometrical and physical properties is presented.In order to determine the influence of geometrical packed bed properties, 16different packed beds were used. The covered range of length to diameter ratio ofbed L/D was 0.24≤L/D≤1.46. The range of diameter of bed to average diameter ofpacking material D/d was 5.72≤D/d≤17.16. The range of average diameter ofpacking material to length of bed d/L was 0.04≤d/L≤0.72 and the range of packedbed porosity ε was 0.36≤ε≤0.56.The packing materials which were used in the experimental study werechickpea, two different sized zeolite, and glass bead. These packing materials wereplaced into the bed with a random loose packing method. The geometrical andphysical properties of the packing materials were used as common variablesincluding average diameter of packing material d in the range of 6 mm≤d≤18 mm,packing material density ρm in the range of 640 kg/m3≤ρm≤2675 kg/m3,and particlesphericity Φ in the range of 0.55 ≤Φ≤ 1.0.In the covered 64 separate test cases, pressure drop across the bed and exitcross-sectional velocity distribution were measured, friction factor in each case wascalculated for a flow Reynolds number range of 15000≤Re≤33000 and particleReynolds number range of 708.2≤Rep≤7772.73. Measured pressure drops, ΔPBed,were compared with ΔPErgun; calculated pressure drops using well-known Ergun?siiiEquation. The range of ΔPBed/ ΔPErgun was 0.8≤ΔPBed/ΔPErgun≤1.25 due to the utilizedΦ range.Experimental data were also presented in terms of non-dimensional parametersdefined originally through a correlation study involving ΔP* and d/L, ΔP* andRep(d/L), ΔP* and εRep(d/L), ΔPBed/ΔPEmpty and Rep(d/L) and finally between Rep(d/L) and Reexit. These correlations seem to be valid in the covered ranges of theexperimental study regarding the variables of the packed bed and particularly Rep.Key Words: Packed Bed, Pressure Drop, Ergun?s Equation, Flow ReynoldsNumber, Particle Reynolds Number, Exit Reynolds Number, Friction Factor, BedPorosity, Sphericity.iv