For a Newtonian fluid, if a given stress is applied, the fluid will respond with a shear rate proportional to the applied stress. The constant of proportionality is called the viscosity, and is clear and unambiguous. Many fluids, such as water or oils, can be appropriately described as ...
For flow through porous media in the Darcy regime, the fluid-solid interaction term is written in terms of the interstitial wall shear stress which is a function of the average interstitial channel velocities. The wall shear stress is obtained by assuming fully developed flow in the interstitial ...
tensor that does not depend on the stress state and velocity of the flow. If the fluid is also isotropic (that is, its mechanical properties are the same along any direction), the viscosity tensor reduces to two real coefficients, describing the fluid's resistance to continuous shear ...
(i.e., a solid) as the shear rate approaches zero. The fluid acts like an elastic solid if theapplied shear stressis below thecritical shear stress, or yield stress.(8)If the stress exceeds the yield value, the material acts like a fluid. An apparentplastic viscositycan be defined ...
Wall shear stress in distensible, porous, elastic and anisotropic tubes, for two-phase pulsatile flows of non-Newtonian fluidsThe present work deals with a two-fluid model for blood flow through deformable tubes of small diameter. The two-fluid flow consists of a core (suspension of red ...
newtonianfluid-牛顿流体 系统标签: newtonianfluid流体fluidstensorshear Newtonianfluid Incontinuummechanics,afluidissaidtobeNewtonianiftheviscousstressesthatarisefromitsflow,atevery point,areproportionaltothelocalstrainrate—therateofchangeofitsdeformationovertime.[1][2][3]Thatis equivalenttosayingthatthoseforcesare...
infinite-shear rate viscosity, Pa s [η]: intrinsic viscosity Λ: time constant in Carreau model, s µ: Newtonian viscosity, Pa s ρ: fluid density, kg/m3 τw: shear stress at the wall of a circular pipe, Pa \(\bar \tau _w \): ...
Since the shear rate of a non-Newtonian fluid is of importance in fixing the rheological or viscometric behavior of such a material, the present study has ... AB Metzner,RE Otto - 《Aiche Journal》 被引量: 1570发表: 1957年 Rheology of non-Newtonian fluids: A new flow equation for pseud...
The fluidity model ofHildebrandhas been applied to dilute aqueous polymer solutions exhibiting non-Newtonian behaviour. As for Newtonian fluids, it is found that the temperature dependence of apparent viscosity of non-Newtonian fluids is determined entirely by the temperature dependence of fluid density....
The constant proportionality is known as dynamic viscosity of fluid. The shear stress and the rate of deformation are normally expressed by the Newton's law of viscosity which can be written mathematically as: (2.38)τ=μdduxdy=μ(γ) Here: τ = shear stress, Pa μd = dynamic viscosity,...