Unreferenced date December 2009 John Philip 1957 described sorptivity as a measure of the capacity of the medium to absorb or desorb liquid by capillarity . Calculation of the true sorptivity required numerical iterative procedures dependent on soil water content and diffusivity. John Philip 1969 showed that sorptivity can be determined from horizontal infiltration where water flow is mostly controlled by capillary absorption math I S sqrt t math where S is sorptivity, I is the cumulative infiltration at time, t . For vertical infiltration, Philip s solution is adated using a parameter A sub 1 sub . This results in the following equations, which are valid for short times cumulative math I S sqrt t A 1 t math , rate math i 0.5 S sqrt t A 1 math where the sorptivity S is defined when a sharp wetting front L sub f sub exists, as math S theta 0 , theta i frac theta 0 theta i L f t 1 2 math Category Soil physics ... more details
attention has been given mainly to the sorptivity apparatus of Dirksen 1975 which used a ceramic plate as a base. Based on this design, Brent Clothier and Ian White 1981 developed the sorptivity tube which can provide a constant negative potential tension on the soil surface. However, the sorptivity ... 0 pi r math References Clothier, B.E., White, I., 1981. Measurement of sorptivity and soil water diffusivity ... of soil water diffusivity by sorptivity measurements. Soil Science Society of America Proceedings ... more details
, with a sorptivity of 5.0 mm min sup 1 2 sup and a porosity of 0.25. When a dry porous medium ... where S is the sorptivity of the medium, with dimensions m s sup 1 2 sup or mm min sup 1 2 sup . The quantity ... use the quantity S f as the sorptivity. ref name hall hoff C. Hall, W.D. Hoff, Water transport ... where gravity and evaporation do not play a role. Sorptivity is a relevant property of building materials ... for the sorptivity of building materials are in the table below. class wikitable Material Sorptivity ... more details
John Robert Philip Royal Society FRS ref cite doi 10.1098 rsbm.2005.0021 ref 18 January 1927, Ballarat spaced ndash 26 June 1999, Amsterdam was an Australian soil physicist, internationally recognized for his contributions to the understanding of movement of water, energy and gases. While he never performed his own experimental work, he was recognised for his skills in mathematics that could be used to explain physical processes and solve real world problems. His interests were not limited to Environmental mechanics and things mathematical, but included a keen interest in the arts. He was a published poet and a panelist on the Sulman Prize for Architecture. His poetry appears in anthologies edited by Judith Wright and in The Oxford Book of Australian Verse . Education and positions He was a recipient of a Scholarship for Scotch College, Melbourne, where he matriculated at age 13. He studied for his Bachelor of Civil Engineering, University of Melbourne 1943 1946 . Appointed to the CSIR Irrigation Research Station, Griffith. CSIRO s Plant Industry in Deniliquin 1951 . Engineer for the Queensland Water Supply Commission. CSIRO Division of Plant Industry. Foundation chief of the new Centre for Environmental Mechanics 1971 1992 . Foundation director of the CSIRO Institute of Physical Sciences 1980 1983 . Retired 1992. Research The major and most recognised area of Philip s research was his work on the theory of infiltration hydrology infiltration . He derived the theory for one dimensional infiltration and developed equations which described the infiltration on both a short term and long term scale, with the revelation that when ponded infiltration in uniform soils occurs, the flow will approach the saturated hydraulic conductivity math I S sqrt t A t math where S is sorptivity and A is the steady state infiltration rate. Other areas of research include Examining heat and mass transfer in soils. Philip also considered the importance of relationships between organisms an ... more details
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