The Dufour effect is the
energy flux Energy flux is the rate of transfer of energy through a surface. The quantity is defined in two different ways, depending on the context:
# Total rate of energy transfer (not per unit area); SI units: W = J⋅s−1.
# Specific rate of energy transfe ...
due to a mass
concentration gradient
Molecular diffusion, often simply called diffusion, is the thermal motion of all (liquid or gas) particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size (mass) of ...
occurring as a coupled effect of
irreversible process
In science, a process that is not reversible is called irreversible. This concept arises frequently in thermodynamics. All complex natural processes are irreversible, although a phase transition at the coexistence temperature (e.g. melting of ic ...
es, named after L. Dufour. It is the reciprocal phenomenon to the
Soret effect
Thermophoresis (also thermomigration, thermodiffusion, the Soret effect, or the Ludwig–Soret effect) is a phenomenon observed in mixtures of mobile particles where the different particle types exhibit different responses to the force of a temper ...
. The concentration gradient results in a temperature change. For binary liquid mixtures, the Dufour effect is usually considered negligible, whereas in binary gas mixtures the effect can be significant.
References
Thermodynamics
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