Newtonian fluids

E32274

continuum material fluid idealized fluid model

Newtonian fluids are idealized fluids whose viscosity remains constant regardless of the applied shear rate, leading to a linear relationship between shear stress and strain rate.

Observed surface forms (2)

Surface form	Occurrences
Newtonian fluid	0
Newton’s law of viscosity	1

Statements (48)

Predicate	Object
instanceOf	continuum material ⓘ fluid ⓘ idealized fluid model ⓘ
appliesTo	simple shear flows ⓘ unidirectional laminar flow ⓘ
assumptionIn	derivation of Navier–Stokes equations ⓘ
contrastedWith	non-Newtonian fluid ⓘ
dependsOn	pressure for viscosity value ⓘ temperature for viscosity value ⓘ
describedBy	Newtonian fluids self-linksurface differs ⓘ surface form: Newton’s law of viscosity
hasExample	air at standard conditions ⓘ light mineral oils ⓘ most simple gases ⓘ water at moderate conditions ⓘ
hasLimitation	does not capture viscoelastic effects ⓘ does not model polymer melts accurately ⓘ does not model suspensions accurately ⓘ
hasParameter	dynamic viscosity μ ⓘ kinematic viscosity ν ⓘ
hasProperty	constant viscosity at given temperature and pressure ⓘ isotropic viscous behavior ⓘ linear constitutive relation between stress and rate-of-strain tensor ⓘ linear stress–strain-rate relationship ⓘ no normal stress differences in simple shear ⓘ no shear-thickening behavior ⓘ no shear-thinning behavior ⓘ no viscoelastic memory effects ⓘ no yield stress ⓘ normal stresses proportional to volumetric strain rate ⓘ rate-type behavior without elasticity ⓘ shear stress proportional to shear rate ⓘ stress depends only on instantaneous rate of deformation ⓘ time-independent viscosity ⓘ viscosity independent of flow history ⓘ viscosity independent of shear rate ⓘ
mathematicalForm	τ_ij = 2 μ e_ij + λ δ_ij ∇·v ⓘ
namedAfter	Isaac Newton ⓘ
obeysEquation	τ = μ (du/dy) ⓘ
usedAs	baseline assumption in many engineering calculations ⓘ reference model in rheology ⓘ
usedIn	Navier–Stokes equations ⓘ boundary layer theory ⓘ computational fluid dynamics ⓘ continuum mechanics ⓘ fluid mechanics ⓘ lubrication theory ⓘ pipe flow analysis ⓘ rheology ⓘ

Referenced by (3)

Full triples — surface form annotated when it differs from this entity's canonical label.

Navier–Stokes equations → appliesTo → Newtonian fluids ⓘ

Stokes–Einstein relation → appliesTo → Newtonian fluids ⓘ

Newtonian fluids → describedBy → Newtonian fluids self-linksurface differs ⓘ

subject surface form: Newtonian fluid

this entity surface form: Newton’s law of viscosity