diffusivity


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Related to diffusivity: eddy diffusivity, magnetic diffusivity

diffusivity

[dif·yü′ziv·əd·ē]
(thermodynamics)
The quantity of heat passing normally through a unit area per unit time divided by the product of specific heat, density, and temperature gradient. Also known as thermal diffusivity; thermometric conductivity.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
All of the test images corrupted by speckle noise are filtered using diffusivity functions of Perona Malik, Charbonnier, and Weickert.
(2015) evaluated the whole baru almond drying kinetics and obtained diffusivity values from 18.15 x [10.sup.-11] to 37.08 x [10.sup.-11] [m.sup.2] [s.sup.-1] for the temperatures of 50, 60 and 70 [degrees]C, showing that the diffusivity values also increased when the drying temperature increased.
where [D.sub.eff] is the effective moisture diffusivity ([m.sup.2]/s); [D.sub.cal] is the estimate moisture diffusivity ([m.sup.2]/s); r is the volume equivalent radius of GB seeds, with 0.769 x [10.sup.-2] m as its value; a is the scale parameter of Weibull distribution; [R.sub.g] is the physical dimension constant.
In this paper, we present an original experimental procedure for the study of the gas permeation process which permits accurate evaluation of the gas diffusivity (and permeability) of thin polymer films and processes characterized by short transient times: this often occurs in the permeation of small-size penetrants and in high-temperature processes.
C is an instrumental factor, f is the frequency of light modulated, k is the thermal conductivity, [alpha] is thermal diffusivity, [l.sub.i] is the thickness of the layer i, [[sigma].sub.j] is the complex TWs diffusion coefficient [[sigma].sub.j] = (1 + i)[a.sub.j] a is the reciprocal of the thermal diffusion length [mu], a = 1/[mu], and [mu] = [([alpha]/[pi]f).sup.1/2].
To further investigate the effects of HTP process on the properties of MG, the thermal diffusivity of MG with and without HTP was measured at various temperatures.
The diffusivity [D.sub.2A] of [H.sub.2A] dimer is known [10, 14, 15] to be 2 x [10.sup.-13] [cm.sup.2]/s at 150[degrees]C (for the deuterium isotope).
The effective permeability K, the effective diffusivity parameters [D.sub.b] as well as [D.sub.n] are assumed to be symmetric, continuous and uniformly positive definite with respect to [theta] within every interval [mathematical expression not reproducible].
Keywords: density, specific heat capacity, thermal diffusivity, wood particle