Kinematic viscosity, definition

The same definition of viscosity applies to oil as gas (see Section 5.2.6), but sometimes the kinematic viscosity is quoted. This is the viscosity divided by the density (u = i7p), and has a straight line relationship with temperature. 

In addition, the U.S. Pharmacopoeia includes the explanation of kinematic viscosity [units in stoke (s) and centistoke (cs)], defined as the absolute viscosity divided by the density of the liquid at a definite temperature, p ... 

In this definition, ps and pt are the solid and fluid densities, respectively. The characteristic diameter of the particles is ds (which is used in calculating the projected cross-sectional area of particle in the direction of the flow in the drag law). The kinematic viscosity of the fluid is vf and y is a characteristic strain rate for the flow. In a turbulent flow, y can be approximated by l/r when ds is smaller than the Kolmogorov length scale r. (Unless the turbulence is extremely intense, this will usually be the case for fine particles.) Based on the Stokes... 

By definition, viscosity is the force in dynes required to move a plane of 1 cm2 area at a distance of 1 cm from another plane of 1 cm2 area through a distance of 1 cm in 1 s. In the centimeter-gram-second (cgs) system the unit of viscosity is the poise (P) or centipoise (cP) (1 cP = 0.01 P). Two other terms in common use are kinematic viscosity and fluidity. The kinematic viscosity is the viscosity in centipoise divided by the specific gravity. The unit of kinematic viscosity is the stoke (cm2/s), although centistokes (0.01 cSt) is in more common usage fluidity is simply the reciprocal of viscosity. 

Definition of terms a = diameter of inlet, A = electrode area, b = channel height, C = concentration (mM), F = Faraday constant, D = diffusion coefficient, v = kinematic viscosity, r = radius of tubular electrode, U = average volume flow rate, u = velocity (cm/s), n = number of electrons. Source Adapted from Ref. 84. 

A commonly used expression for this number is Sh = 2.0 - - 0.55Re/ Scp where Rcp = d u —u /i/ is the particle Reynolds number and Scp is the fuel vapor Schmidt number. In this definition v is the carrier phase kinematic viscosity. In Eq. (8.2), one important parameter is the Spalding number Bm = Ypx f)/(1 — Yfx) where Ypx is the fuel mass fraction at the droplet surface, calculated from the fuel vapor partial pressure at the interface ppx which is evaluated from the Clausius-Clapeyron relation ... 

Substituting the information given on kinematic viscosity and liquid velocity into the definitions of the Reynolds and Froude numbers,... 

A rise in the trifunctional unit content from 0 to 1.4 mol% in oligomethylethylsiloxanes leads to sharp growth of the kinematic viscosity. There is a great probability therewith of formation of star-like compounds, and lateral branch lengths exceed a definite critical point, thus resulting in a viscosity increase. A further rise in the trifunctional unit content up to 16.9 mol% results in a kinematic viscosity drop. 

The presence of this property in the system allows one to compose with the dynamic viscosity ri a path linking the concentration of momentum to the local pressure P (shear stress), which constitutes a definition for the operator ambiguously named kinematic viscosity... 

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