Cohesive Nature of Ice Particles and Blocking Phenomenon of Ice/Water Slurry.

Blocking of Snow/Water Slurry Flow in Pipeline Caused by Compression-Strengthening of Snow Column

“…Then, the flow velocity is decreased step-wisely by adjusting the rotation speed of the feeding vortex pump while keeping the fraction constant until the formation of the compressed plug, stopping the flow, is observed at the orifice. Results of fresh snow slurry, thus obtained, are shown in Figure 11, compared with the results of the element test in Figure 10c [16]. They agree fairly well with each other, confirming that the blocking resulting from the compression of fresh snow plug occurs at a tube orifice in pipeline at the same criterion as observed in the element test.…”

“…Although the change in the pressure drop p 2 -p 1 is small in both cases, it would attain a larger value for the fresh snow if snow particles had been supplied continuously as in the case of a slurry flow tube in a pipeline system. The conditions of flow velocity and initial fraction for occurrence of blocking, obtained by the element test, are shown in Figure 10 [16]. In the case of chipped ice, the blocking occurs at an initial fraction higher than around 10%, independent of the flow velocity.…”

“…Figure 11. Blocking condition of fresh-snow/water slurry at a tube orifice in pipeline compared with that of the element test [16].…”

“…To obtain the criterion for the blocking at a tube orifice, two tests were carried out. One was the element test, using an apparatus shown in Figure 8, and, the other, the pipeline blocking test in a vortex-pump and pipeline system, inserted with the tube orifice tested in the element test [15,16].…”