| Summary: | During this study an experimental test facility was designed and constructed with the purpose of
conducting experiments to measure the pressure drop through packed beds of spheres with
varying levels of structuredness. The test facility had to be designed so that the uncertainty in
the measured friction factors would be below ±10% and commissioned to ensure that results
with an acceptable degree of accuracy could be obtained.
Experiments were done on a randomly packed bed and a structured packed bed in order to
demonstrate the proper operation of the test facility. The resulting experimental data was
compared with applicable correlations found from relevant literature. The nuclear safety
standards commission (KTA (1981)) correlation, as well as the relation of Ergun (1952) was
chosen for comparison with the experimental data obtained from the experiment on the
randomly packed bed. The correlation of Wentz and Thodos (1963) was selected for
comparison with the experimental data obtained from the structured packed bed experiment.
The friction factors obtained from the experimental data was found to be higher than the friction
factors calculated with the different correlations for the respective packing configurations. This
could be attributed to the manufacturing process of the packing configurations that resulted in
the surface finish of the particles to be extremely coarse. In order to obtain the desired porosity
within the structured packed bed, cylindrical rods were utilised to separate the particles to
prevent contact between them. Wentz and Thodos (1963) also made use of cylindrical rods,
called distention rods, to make varying porosity possible within the structured packed beds. The cylindrical rods that were utilised during these experiments are larger (in diameter) than those
described in the literature, which could have contributed to the higher pressure drop through the
structured packed bed. Furthermore, it was found that the friction factors derived from the
experimental data increased as the modified Reynolds number was increased. This is a
phenomenon that is not fully understood at this time and further study is proposed.
The operation of the experimental test facility was successfully demonstrated. The
measurements were shown to be repeatable and the uncertainty of the friction factors derived
from the measured data obtained from the test facility was less than 10%, which is satisfactory.
Therefore, the ability to measure the pressure drop through packed beds of spheres with
varying degrees of structuredness has now been established as a result of this research. === Thesis (MIng (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012
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