A number of columns filled with different sizes of glass beads were set up as Darcy columns and changes in specific discharge were observed. Intrinsic Permeabilityįreeze and Cherry (1979) describe the results of hydraulic conductivity experiments used to explore the relationship between physical properties of the porous media and the fluid. These conditions are also referred to as permeable or of low permeability, respectively. If water easily passes through a porous material it is described as having a high hydraulic conductivity if water is poorly transmitted through a material it has a low hydraulic conductivity. However, K is not a velocity, rather it represents the transmission properties of the porous material. Thus, the constant of proportionality, K, has units of velocity (e.g., meters/seconds, meters/day). In this configuration, it becomes clear that the units of K are L/T because Q units are (L 3/T), A units (L 2), h units are (L), and L units are (L). Rearranging Darcy’s law to solve for hydraulic conductivity generates Equation 25. It has direction and magnitude and is represented as a vector however, the first part of this discussion presents it as a scalar value. Particularly striking is the reproducibility and self-consistency of the results obtained.The hydraulic conductivity proportionality constant, K, can be conceptualized as the relative ease of fluid passage through a porous material. Although the present instrument is severely limited in range, the feasibility of measurements at elevated temperatures and pressures by means of the oscillation-type viscometer is clearly demonstrated. The results show good agreement with previously published data and the deviations of experimental points from smoothed curves do not exceed 0.05 per cent. The maximum change in viscosity, at any given temperature over the pressure range covered is 5 per cent. The viscosity of water is shown to have a negative pressure coefficient below 35 C and a positive coefficient above that temperature. The results for compressed water, obtained with the aid of an oscillating sphere, represent absolute measurements, and cover a range from 3 to 340 atm and from 20 to 186 C. The measurements were carried out by means of an oscillating-body-type viscometer in order to develop an alternative method of measurement to the usually employed capillary viscometer, and also to provide an independent check on published data. The paper reports the results of an investigation of the viscosity of steam and compressed water.
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