Department of Mechanical and Aerospace Engieering
Princeton, NJ 08544
In a multicomponent fluid, the species-specific mass diffuion flux is related to the gradients of all the species (and temperature and pressure) by a diffusion coefficient matrix. Normally, this matrix is derived using kinetic theory, and the derivation involved sophisticated mathematics. This paper rederived the classical results---including thermal diffusion---using only macroscopic concepts and equations. In particular, the non-uniqueness of this diffusion coefficient matrix is emphasized and discussed.
Published in Physics of Fluids, Vol. 18, issue #7, July, 2006.
Between Eq.(6) and Eq.(7): "Since mass can neither be created nor destroyed ..."
Reference 19: Its publication year was 1981, not 1961.