• Diffusivity, mass diffusivity or diffusion coefficient is usually written as the proportionality constant between the molar flux due to molecular diffusion...
    14 KB (1,697 words) - 07:04, 19 April 2025
  • different mediums. Diffusivity may refer to: Thermal diffusivity, diffusivity of heat Diffusivity of mass: Mass diffusivity, molecular diffusivity (often called...
    909 bytes (117 words) - 07:02, 18 August 2024
  • is the ratio of the shear component for diffusivity (viscosity divided by density) to the diffusivity for mass transfer D. It physically relates the relative...
    7 KB (843 words) - 04:09, 21 November 2024
  • ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer. The Lewis...
    5 KB (568 words) - 16:59, 31 March 2025
  • can also be used in the study of mass diffusion, in which the thermal diffusivity is replaced by the mass diffusivity. The Fourier number is used in analysis...
    7 KB (1,065 words) - 09:43, 27 February 2025
  • Thermal diffusivity and thermal effusivity are related concepts and quantities used to simulate non-equilibrium thermodynamics. Diffusivity is the more...
    13 KB (1,102 words) - 17:52, 29 March 2025
  • Thumbnail for Kinetic theory of gases
    as transport properties such as viscosity, thermal conductivity and mass diffusivity. The basic version of the model describes an ideal gas. It treats the...
    62 KB (8,974 words) - 14:30, 29 April 2025
  • concentration for mass transfer, temperature for heat transfer), D is the diffusivity (also called diffusion coefficient), such as mass diffusivity for particle...
    20 KB (2,738 words) - 05:54, 7 May 2025
  • Thumbnail for Viscosity
    the mass and heat fluxes, and D {\displaystyle D} and k t {\displaystyle k_{t}} are the mass diffusivity and thermal conductivity. The fact that mass, momentum...
    99 KB (11,463 words) - 16:25, 8 May 2025
  • {\mbox{Total mass transfer rate}}{\mbox{Diffusion rate}}}} where L is a characteristic length (m) D is mass diffusivity (m2 s−1) h is the convective mass transfer...
    4 KB (593 words) - 18:00, 31 December 2024
  • Self-diffusion describes the diffusive motions of molecules within themselves e.g. the movement of a water molecule in water. According to the IUPAC definition...
    3 KB (313 words) - 07:15, 1 March 2025
  • kinematic viscosity. D is the mass diffusivity. ε is the rate of dissipation of turbulence kinetic energy per unit mass. Similar to the Kolmogorov microscales...
    2 KB (280 words) - 04:16, 17 October 2024
  • Thumbnail for Knudsen diffusion
    SI units), molar mass M A {\displaystyle M_{A}} is expressed in units of kg/mol, and temperature T (in kelvins). Knudsen diffusivity D K A {\displaystyle...
    6 KB (1,042 words) - 23:53, 2 March 2025
  • Thumbnail for Atomic diffusion
    diffusion occurs much faster than lattice diffusion. Kirkendall effect Mass diffusivity Heitjans, P.; Karger, J., eds. (2005). Diffusion in condensed matter:...
    4 KB (466 words) - 08:33, 8 April 2023
  • transfer, the comparison is between viscous diffusivity ( ν {\displaystyle {\nu }} ) and mass Diffusivity ( D {\displaystyle {D}} ), given by the Schmidt...
    26 KB (3,501 words) - 18:15, 19 May 2025
  • number (i.e. a nonzero magnetic diffusivity) is associated with violation of Alfvén's theorem. The magnetic diffusivity has SI units of m²/s and is defined...
    2 KB (276 words) - 15:53, 2 April 2024
  • it to expand in all directions without rupture. Mass diffusivity: Ability of one substance to diffuse through another Plasticity: Ability of a material...
    10 KB (1,148 words) - 10:35, 11 March 2025
  • permeate, a material's intrinsic permeability, and the materials' mass diffusivity. Permeation is modeled by equations such as Fick's laws of diffusion...
    14 KB (2,095 words) - 02:44, 30 November 2024
  • Thumbnail for Biot number
    {k_{c}}}  : convective mass transfer coefficient (analogous to the h of the heat transfer problem) D {\displaystyle D}  : mass diffusivity (analogous to the...
    9 KB (1,285 words) - 19:40, 28 December 2024
  • mass transfer the Prandtl number is replaced by the Schmidt number, Sc, which expresses the ratio of the momentum diffusivity to the mass diffusivity...
    1 KB (199 words) - 09:29, 17 January 2025
  • Thumbnail for Brownian motion
    probability of displacement q {\displaystyle q} , is interpreted as mass diffusivity D: D = ∫ − ∞ ∞ q 2 2 τ φ ( q ) d q . {\displaystyle D=\int _{-\infty...
    55 KB (7,140 words) - 01:57, 7 May 2025
  • thermal diffusivity The Be number plays in forced convection the same role that the Rayleigh number plays in natural convection. In the context of mass transfer...
    10 KB (1,552 words) - 09:25, 17 January 2025
  • ratio of momentum diffusivity to thermal diffusivity. The Prandtl number is given as: P r = ν α = momentum diffusivity thermal diffusivity = μ / ρ k / ( c...
    8 KB (1,106 words) - 16:37, 20 September 2024
  • Thumbnail for Eddy diffusion
    now neglect the molecular diffusivity K 0 {\textstyle K_{0}} , since it is usually significantly smaller than eddy diffusivity, and would steer attention...
    55 KB (7,956 words) - 18:37, 11 May 2025
  • raffinate and strip product is differentiated. With a typical liquid mass diffusivity in the order of 10−9 m2/s, the characteristic time for diffusion through...
    6 KB (913 words) - 14:00, 26 August 2024
  • _{L}\,\mathrm {Pr} ,} where Pr the Prandtl number, and α the thermal diffusivity, α = k ρ c p , {\displaystyle \alpha ={\frac {k}{\rho c_{p}}},} where...
    4 KB (560 words) - 16:23, 6 May 2025
  • Thumbnail for Boundary layer
    momentum diffusivity. In the energy balance this is replaced by thermal diffusivity α = k / ρ C P {\displaystyle \alpha ={k/\rho C_{P}}} , and by mass diffusivity...
    49 KB (7,735 words) - 11:55, 6 February 2025
  • become significant below ~0.4 Tmelt in FCC metals. Kirkendall effect Mass diffusivity P. Heitjans, J. Karger, Ed, “Diffusion in condensed matter: Methods...
    2 KB (291 words) - 05:27, 19 October 2023
  • numbers in transport phenomena of mass, momentum, and energy are principally analyzed by the ratio of effective diffusivities in each transport mechanism....
    29 KB (816 words) - 16:09, 13 March 2025
  • number is the dimensionless number for the ratio of momentum diffusivity to thermal diffusivity. The thermal entrance length for a fluid with a Prandtl number...
    19 KB (2,803 words) - 14:16, 23 April 2025