Predicting Incipient Fluidization of Fine Sands in Unbounded Domains
Publication: Journal of Hydraulic Engineering
Volume 116, Issue 12
Abstract
From the theory of flow through porous media, the governing equation for hydraulic head is developed for flow emanating from small holes in a pipe buried in fine sand in the coastal environment. Calculated Reynolds numbers for sand grain sizes typically found in tidal inlets (less than 0.5 mm) indicate that the generalized Darcy law remains valid up to fluidization. The head distribution in the domain is obtained from the two‐dimensional finite element method and validated with experimental results. The theoretical critical hydraulic gradient is used to predict the incipient fluidization flow rate conditions for the available experimental data as well as for a wide range of field situations. A practical fluidization‐system chart is developed for determination of the flow rate required for incipient fluidization. For a pipe diameter of 0.3 m, the chart provides flow rates for burial depths ranging between 1.5 and 12.2 m. The head loss through the bed at incipient conditions is 1.9–2.9 times the bed depth for the range of simulated conditions.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Amirtharajah, A. (1970). “Expansion of graded sand filters during backwashing,” thesis presented to the Iowa State University, at Ames, Iowa, in partial fulfillment for the requirements for the degree of Master of Science.
2.
Amirtharajah, A., and Cleasby, J. L. (1972). “Prediction of expansion of filters during backwash.” J. American Water Works Assoc., 64(1), 47–52.
3.
Bear, J. (1972). Dynamics of fluids in porous media. Elsevier, New York, N.Y.
4.
Bruun, P. F., and Gerritsen (1959). “Natural bypassing of sand at coastal inlets.” J. Wtrwys. and Harb. Div., ASCE, 85(4), 75–107.
5.
Cleasby, J. L., and Fan, K. S. (1981). “Predicting fluidization and expansion of filter media.” J. Emir. Engrg. Div., ASCE, 107(3), 455–471.
6.
Clifford, J. (1989). “Slurry removal from the fluidized region of an unbounded domain: An experimental study,” thesis presented to Lehigh University, at Bethlehem, Pennsylvania, in partial fulfillment for the requirements for the degree of Master of Science.
7.
Couderc, J.‐P. (1985). “Incipient fluidization and particulate systems.” Fluidization, J. F. Davidson, R. Clift, and D. Harrison, eds., 2nd Ed., Academic Press, London, England, 7–23.
8.
Davidson, J. F., Clift, R., and Harrison, D., eds., (1985). Fluidization, 2nd Ed., Academic Press, London, England.
9.
Dharmarajah, A. H., and Cleasby, J. L. (1986). “Predicting the expansion of filter bed material.” J. American Water Works Assoc, 78(12), 66–76.
10.
Fan, K.‐S. (1978). “Sphericity and fluidization of granular filter media,” thesis presented to the Iowa State University, at Ames, Iowa, in partial fulfillment of the requirements for the degree of Master of Science.
11.
Irmay, S. (1958). “On the theoretical derivation of Darcy and Forchheimer formulas.” Trans., American Geophysical Union, 39, 702–707.
12.
Kelley, J. T. (1977). “Fluidization applied to sediment transport, thesis presented to Lehigh University, at Bethlehem, Pennsylvania, in partial fulfillment of the requirements for the degree of Master of Science.
13.
Lennon, G. P., and Chang, F.‐T. (1989). “Fluidization of granular media in unbounded two‐dimensional domains: Numerical calculations of incipient conditions.” Imbt Hydraulics Lab Report No. IHL‐124‐89, Lehigh Univ., Bethlehem, Pa.
14.
Parks, J. M., Weisman, R. N., and Collins, A. G. (1983). “Fluidization applied to sediment transport (FAST) as an alternative to maintenance dredging of navigation channels in tidal inlets.” Wastes in the ocean, volume II: Dredged material disposal in the ocean, D. R. Kester, B. H. Ketchum, I. W. Duedall, and P. K. Park, eds., John Wiley and Sons, Inc., New York, N.Y.
15.
Roberts, E. W., Weisman, R. N., and Lennon, G. P. (1986). “Fluidization of granular media in unbounded two‐dimensional domains: An experimental study,” Imbt Hydraulics Lab Report No. 1HL‐109‐86, Lehigh Univ., Bethlehem, Pa.
16.
Weisman, R. N., and Collins, A. G. (1979). “Stabilization of tidal inlet channels—Design recommendations.” Fritz Engineering Lab Report No. 710.3, Lehigh Univ., Bethlehem, Pa.
17.
Weisman, R. N., Collins, A. G., and Parks, J. M. (1982). “Maintaining tidal inlet channels by fluidization.” Journal Wtrwy. Port, Coast., and Oc. Div., ASCE, 108(4), 526–538.
18.
Weisman, R. N., Lennon, G. P., and Roberts, E. W. (1988). “Experiment on fluidization in unbounded domains.” J. Hydr. Engrg., ASCE, 114(5), 502–515.
19.
Wen, C. Y., and Yu, Y. H. (1966). “Mechanics of fluidization.” Chemical Engrg. Progress Symp. Series 62, American Institute of Chemical Engineers, 100–111.
Information & Authors
Information
Published In
Copyright
Copyright © 1990 ASCE.
History
Published online: Dec 1, 1990
Published in print: Dec 1990
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.