Difference between revisions of "Darcy's law"
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− | All the experiments were carried out with water changing the type of sand pack. The effects of fluid density and viscosity on the flow was not investigated<ref name=DakeF/> and therefore | + | All the experiments were carried out with water changing the type of sand pack. The effects of fluid density and viscosity on the flow was not investigated<ref name=DakeF/> and therefore accounted for in the constant '''K'''. |
Subsequently, others experiments performed with a variety of different liquids revealed the dependence of fluid flow on fluid density and viscosity. | Subsequently, others experiments performed with a variety of different liquids revealed the dependence of fluid flow on fluid density and viscosity. |
Revision as of 15:38, 22 July 2019
Contents
Darcy's law
Darcy's law is the fundamental law of fluid motion in porous media published by Henry Darcy in 1856 [1]. French engineer Henry Darcy has earned himself a special place in history as the first experimental reservoir engineer [2].
Darcy's law has been successfully applied to determine the flow through permeable media since the early days of Petroleum Engineering.
The basic form of Darcy's law is very similar to in form to other physical laws. For example Fourier's law for heat conduction and Ohm's law for flow of electricity [3].
Darcy's law formula:
Darcy's law History
Henry Darcy worked on the design of a filter large enough to process the Dijon towns daily water requirement [2].
By flowing water through the sand pack Darcy established that, for any flow rate, the velocity of the flow was directly proportional to the difference in manometric heights[2]:
All the experiments were carried out with water changing the type of sand pack. The effects of fluid density and viscosity on the flow was not investigated[2] and therefore accounted for in the constant K.
Subsequently, others experiments performed with a variety of different liquids revealed the dependence of fluid flow on fluid density and viscosity.
The new constant k has therefore been isolated as being solely dependent on the nature of sand and is described as the permeability[2].
Darcy's law Equation
Differential form
If distance is measured positive in the direction of flow, then the pressure gradient must be negative in the same direction since fluids move from high to low pressure[2]. Therefore, Darcy's law is:
Linear form
Radial form
Conditions
- Single fluid
- Steady stay flow
- Constant fluid compressibility
- Constant temperature
Darcy's law Equation Example
The permeability of 1 Darcy defined as permeability which allows fluid with viscosity of 1 centipoise flow a distance of 1 cm with velocity of 1 cc/sec through the crossectional area of 1 cm2 with the pressure gradient of 1 atm.
Inflow Equations Derivation
Derivation of the Linear and Radial Inflow Equations
Nomenclature
- = cross-sectional area, cm2
- = permeability, d
- = length, cm
- = pressure, atm
- = flow rate, cm3/sec
Greek symbols
- = Darcy's law fluid viscosity, cp
See Also
- Converting from the Darcy's law units to the field units in the well's inflow equations 141.2 derivation
- Calculating Production Potential with the Darcy's law
References
- ↑ Darcy, Henry (1856). "Les Fontaines Publiques de la Ville de Dijon". Paris: Victor Dalmont.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Dake, L.P. (1978). Fundamentals of Reservoir Engineering. Amsterdam, Hetherlands: Elsevier Science.
- ↑ Wolcott, Don (2009). Applied Waterflood Field Development. Houston: Energy Tribune Publishing Inc.