Darcy’s law
E647520
Darcy’s law is a fundamental equation in fluid mechanics that relates the volumetric flow rate of a fluid through a porous medium to the pressure gradient, permeability, and fluid viscosity.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Darcy’s law canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T7189109 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Darcy’s law Context triple: [Saffman–Taylor instability, governingEquations, Darcy’s law]
-
A.
Stokes' law
Stokes' law is a fundamental equation in fluid dynamics that describes the drag force experienced by small spherical particles moving slowly through a viscous fluid.
-
B.
Meyer-Peter–Müller bed-load formula
The Meyer-Peter–Müller bed-load formula is a classic empirical equation in fluvial hydraulics used to estimate the transport rate of coarse sediment along a riverbed under given flow conditions.
-
C.
Charney equation
The Charney equation is a fundamental quasi-geostrophic equation in atmospheric dynamics that describes large-scale Rossby waves and mid-latitude weather patterns on a rotating planet.
-
D.
Einstein bed-load function
The Einstein bed-load function is a seminal hydraulic engineering formula developed by Hans Albert Einstein to predict the transport rate of sediment particles rolling and sliding along a riverbed under flowing water.
-
E.
Fick's first law of diffusion
Fick's first law of diffusion is a fundamental physical law that relates the diffusive flux of particles to the spatial gradient of their concentration, describing how substances move from regions of high to low concentration.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Darcy’s law Target entity description: Darcy’s law is a fundamental equation in fluid mechanics that relates the volumetric flow rate of a fluid through a porous medium to the pressure gradient, permeability, and fluid viscosity.
-
A.
Stokes' law
Stokes' law is a fundamental equation in fluid dynamics that describes the drag force experienced by small spherical particles moving slowly through a viscous fluid.
-
B.
Meyer-Peter–Müller bed-load formula
The Meyer-Peter–Müller bed-load formula is a classic empirical equation in fluvial hydraulics used to estimate the transport rate of coarse sediment along a riverbed under given flow conditions.
-
C.
Charney equation
The Charney equation is a fundamental quasi-geostrophic equation in atmospheric dynamics that describes large-scale Rossby waves and mid-latitude weather patterns on a rotating planet.
-
D.
Einstein bed-load function
The Einstein bed-load function is a seminal hydraulic engineering formula developed by Hans Albert Einstein to predict the transport rate of sediment particles rolling and sliding along a riverbed under flowing water.
-
E.
Fick's first law of diffusion
Fick's first law of diffusion is a fundamental physical law that relates the diffusive flux of particles to the spatial gradient of their concentration, describing how substances move from regions of high to low concentration.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
empirical law
ⓘ
law in fluid mechanics ⓘ law in hydrogeology ⓘ physical law ⓘ |
| appliesTo | laminar flow in porous media ⓘ |
| assumes |
homogeneous porous medium
ⓘ
incompressible fluid ⓘ isotropic porous medium ⓘ steady-state flow ⓘ |
| category |
porous media flow
ⓘ
transport phenomena ⓘ |
| describes | flow of fluid through porous media ⓘ |
| expressedAs | specific discharge q = -K (dh/dl) ⓘ |
| field |
fluid mechanics
ⓘ
linked to:
Fluid Mechanics
groundwater hydraulics ⓘ hydrogeology ⓘ petroleum engineering ⓘ soil mechanics ⓘ |
| generalizedBy | Forchheimer equation ⓘ |
| hasForm | Q = -k A (ΔP / (μ L)) ⓘ |
| hasLimitation |
does not accurately describe turbulent flow in porous media
ⓘ
less accurate for very high flow velocities ⓘ |
| implies |
flow rate is inversely proportional to viscosity
ⓘ
flow rate is proportional to permeability ⓘ flow rate is proportional to pressure gradient ⓘ |
| introducedIn | 1856 ⓘ |
| involvesQuantity |
cross-sectional area
ⓘ
dynamic viscosity ⓘ hydraulic conductivity ⓘ length of flow path ⓘ permeability ⓘ pressure gradient ⓘ volumetric flow rate ⓘ |
| mathematicalForm | linear relationship between flux and pressure gradient ⓘ |
| namedAfter | Henry Darcy ⓘ |
| originatedFrom | experiments on water flow through sand filters in Dijon ⓘ |
| permeabilityUnit |
darcy
ⓘ
square metre ⓘ |
| relatedTo |
Darcy–Weisbach equation
ⓘ
Hagen–Poiseuille equation ⓘ |
| relates |
volumetric flow rate to fluid viscosity
ⓘ
volumetric flow rate to permeability ⓘ volumetric flow rate to pressure gradient ⓘ |
| usedIn |
contaminant transport modeling
ⓘ
filtration processes ⓘ groundwater flow modeling ⓘ reservoir engineering ⓘ soil drainage analysis ⓘ |
| validWhen | Reynolds number in pores is low ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Darcy’s law Description of subject: Darcy’s law is a fundamental equation in fluid mechanics that relates the volumetric flow rate of a fluid through a porous medium to the pressure gradient, permeability, and fluid viscosity.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.