Viscosity Centipoise

DARCY (D). A unit of permeability of a porous medium. One darcy equals 1 cF (cm/s)(cm/atm) equals 0.986923 square micrometers. (A permeability of 1 daicy will allow the flow of 1 cubic centimeter per second of fluid of 1 centipoise viscosity through an area of 1 square centimeter under a pressure gradient of 1 atmosphere per centimeter.)... 

In the petroleum industry it is usual to define the permeability in darcys for a fluid of 1 centipoise viscosity. In this case the result is 164 darcys. 

Permeability is a measure of the amount of gas that will flow through the cement per unit area of its cross section per unit time. It is measured in darcies. One darcy is equal to the flow of 1 cm per second of a fluid of 1 centipoise viscosity through an area of 1 cm under a pressure gradient of 1 atmosphere per cm [5]. 

A darcy is defined by the following characteristics for a flow system. Thus, a porous medium having a permeability of 1 darcy will, at standard conditions, permit the flow of a fluid of 1 centipoise viscosity at the superficial rate of 1 cm/sec under a pressure gradient of 1 atm/cm. In the formula above, v is in cm/sec, K is in darcies, is in centipoises (centigrams/cm-sec), P is in atm, and x is in cm. The actual equivalent units for K in darcies would be centigram-cm/atm-sec. It may be converted to cm /sec by multiplying... 

What minimum flow rate in cm/sec is required in a 10-m length of open straight pipe of 2 cm inside diameter to obtain a uniformly mixed paint from two components of combined density 1,100 kg/m and 1.912 centipoise viscosity ... 

Columns of granular carbon are designed for economical and convenient working pressure. Actual operating pressure seldom rises above one pound per foot of bed depth even with a liquid of 10 centipoise viscosity. Good design allows for some excess pressure. 

In the event that Dow silicone oil (Coming. 200-Iluld 20 centipoise viscosity) was used to prevent sample evaporation, sample recoveiy can be readily obtained by pipetting out the entire sample (including oil) onto a Teflon dish. The oil will stick to the Teflon as the bead of sample is rolled around the dish (10). 

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