Page 877 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

832 Appendix E: Porous Media Hydraulics

measure. The mathematics may be described by Freeze, R. A., Translation of: Darcy, H., Determination of the laws of
probability theory, with each step a result of ‘‘coin- the flow of water through sand, from pp. 590–594 of Les
Fontaines Publiques de la Ville de Dijon, Victor Dalmont,
flipping.’’ In flow through porous media, dispersion
Paris, 647 pp. 1856. Translation reprinted in Ground Water,
occurs due to the random distribution of pore veloci-
32(1):260–261, 1994.
ties, which are larger and smaller than the mean Freeze, R. A., Henry Darcy and the fountains of Dijon, Ground
velocity. Water, 32(1):23–30, January–February 1994.
Forchheimer: German researcher who published in 1901 the Hendricks, D. W., Barrett, J. M., Bryck, J., Collins, M. R., Janonis,
nonlinear relationship between hydraulic gradient B. A., and Logsdon, G. S., Manual of Design for Slow Sand
and velocity that occurs at higher Reynolds numbers Filtration, AWWA Research Foundation and American Water
Association, Denver 1991.
(see Trussell and Chang, 1999).
Hsu, S., Dispersion and wave fronts, MS Thesis, Department of Civil
Hydraulic conductivity: The constant K in Darcy’s law, i.e.,
Engineering, Colorado State University, Fort Collins, CO,
v ¼ K(dh=dz). The term K incorporates fluid proper- 1994.
ties r and m which are the functions of temperature. Kasenow, M., Applied Ground-Water Hydrology and Well
Intrinsic permeability: The constant k in Darcy’s law, i.e., Hydraulics, Water Resources Publications, Fort Collins, CO,
v ¼ (krg=m)(dh=dz). The k term is a property of the 1997.
2
porous medium with dimensions, L and is preferred McWhorter, D. B. and Sunada, D. K., Ground-Water Hydrology and
Hydraulics, Water Resources Publications, Denver, CO, 1977.
because the fluid properties, r and m are isolated.
Mosher, R. R. and Hendricks, D. W., Filtration of Giardia Cysts and
Permeability: A qualitative description of a porous medium,
Other Particles under Treatment Plant Conditions, Volume 2:
e.g., ‘‘this soil is highly permeable,’’ meaning the Rapid Rate Filtration Using Field Scale Pilot Filters on the
soil has a relatively high intrinsic permeability. Cache La Poudre River, AWWA Research Foundation Report
Hydraulic conductivity is also loosely referred to as for Contract 80-84, May, 1986.
permeability. Muskat, M., The Flow of Homogeneous Fluids through Porous
Superficial velocity: Defined as flow divided by Media, J. W. Edwards, Inc., Ann Arbor, MI, 1946
Seelaus, T., Hendricks, D. W., and Janonis, B., Filtration of Giardia
cross-sectional area, i.e., v ¼ Q=A.
Cysts and Other Particles Under Treatment Plant Conditions,
Uniformity coefficient (UC): Defined, UC ¼ d 60 =d 10 .
Volume 1: Slow Sand Filtration at Empire Colorado, AWWA
Research Foundation Report for Contract 80-84, May 1986.
Sheidegger, A. E., The Physics of Flow through Porous Media,
REFERENCES Revised Edition, The Macmillan Co., New York, 1960.
Trussell, R. R. and Chang, M., Review of flow through porous media
Ahmed, N. and Sunada, D., Nonlinear flow in porous media, as applied to headloss in water filters, Journal of Environmen-
J. Hydraulic Engineering Division, ASCE, 95(6):1847–1857,
tal Engineering Division, ASCE, 125(11):998–1005, Novem-
June 1969.
Boulding, J. R., Practical Handbook of Soil, Vadose Zone, and ber 1999.
Trussell, R. R., Chang, M., Lang, J. S., and Hodges, W. E. Jr.,
Ground-Water Contamination—Assessment Prevention, and Estimating the porosity of full-scale anthracite filter, Journal
Remediation, Lewis Publishers, Ann Arbor, MI, 1995.
of AWWA, 91(12):54–63, November 1999.
Brown, G. O., Henry Darcy and the making of a law, Water
Resources Research, 38(7):11-1–11-12, July 2002.
Chang, M., Trussell, R. R., Guzman, V., Martinez, J., and Delany,
C. K., Laboratory studies on the clean bed headloss of filter
media, Aqua, 48:137–145, 1999.