Erosion rates were measured along the length of a tubular flow cell
of type 304 (UNS S30400) stainless steel (SS) carrying dilute slurries
of silica sand (0.43 mm diam) and
smooth glass beads of a similar size. The segmented test cell contained
a sudden constriction, a sudden expansion, and a groove to produce disturbed
flow conditions. Erosion rates were reduced by changes in the cell wall
geometry that resulted from erosion at positions of high local metal
loss and from erosion further downstream because of the reduction in
turbulence and particle dispersion. Smoothing of the sand
particles in the test system halved the erosion rates; however, reduced
erosion rates obtained with the sand were 2 orders of magnitude higher
than those produced with the glass beads. This difference was attributed
to surface microroughness of the particles.
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