Search results
Results From The WOW.Com Content Network
Porosity is a fraction between 0 and 1, typically ranging from less than 0.005 for solid granite to more than 0.5 for peat and clay. The porosity of a rock, or sedimentary layer, is an important consideration when attempting to evaluate the potential volume of water or hydrocarbons it may contain.
The concept of permeability is of importance in determining the flow characteristics of hydrocarbons in oil and gas reservoirs, [4] and of groundwater in aquifers. [5]For a rock to be considered as an exploitable hydrocarbon reservoir without stimulation, its permeability must be greater than approximately 100 md (depending on the nature of the hydrocarbon – gas reservoirs with lower ...
The proportion of empty space in a porous media is called porosity. [9] It is determined by dividing the volume of the pores or voids by the overall volume. It is expressed as a percentage or as a decimal fraction between 0 and 1. Porosity for the majority of rocks ranges from less than 1% to 40%.
Total porosity The volume of the reservoir rock which is fluid (oil, water, gas) filled, expressed as a percentage or a fraction of the gross (bulk) rock volume. Effective porosity The sum of all the interconnected pore space.
The movement of a fluid through porous media is described by the combination of Darcy's law with the principle of conservation of mass in order to express the capillary force or fluid velocity as a function of various other parameters including the effective pore radius, liquid viscosity or permeability. [3]
The Eulerian porosity, (), which measures the porosity with respect to the current or deformed configuration. Specifically, if d V t {\displaystyle \mathrm {d} V_{t}} represents an infinitesimal volume in the deformed material body, then the pore volume is calculated from n ( x ) d V t {\displaystyle n(\mathbf {x} )\mathrm {d} V_{t}} .
Porosimetry is an analytical technique used to determine various quantifiable aspects of a material's porous structure, such as pore diameter, total pore volume, surface area, and bulk and absolute densities. The technique involves the intrusion of a non-wetting liquid (often mercury) at high pressure into a material through the use of a ...
ε is the volume porosity of the bed (dimensionless) δP is the pressure drop across the bed, Pa l is the cylinder length, m η is the air dynamic viscosity, Pa·s Q is the flowrate, m 3 ·s −1. It can be seen that the specific surface is proportional to the square root of the ratio of pressure to flow. Various standard methods have been ...