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Optimal Mass Diffusion Transfer in Solids Using Heat Transfer Similarities

Jaber Samar, Alahmer Ali, Borowski Gabriel, Alsaqoor Sameh

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 4

54--59

EN

A new concept of solid-solid mass diffusion fin was introduced in this paper. The authors described the mass diffusion in fluid flows to analyze the transfer process in solids and its applications, especially in metallurgical research. Using the advantage of the similarity between heat transfer and mass diffusion transfer will make this issue more practical. The authors suggested a new approach to determine the maximum mass diffusion transfer between two solids by implementing of the extended surface on each solid, where the optimal mass diffusion between solids is required. Then, meshing the surfaces together in order to increase the transfer efficiency was carried out. A complete analysis of the extended surfaces design (diffusion fins), its efficiency and effectiveness were presented. Moreover, mathematical models of each consideration were constructed. The authors found that the total surface efficiency increased along with the number of mass diffusion fins attached to the base, but its effectiveness did not. The mass diffusion for an extended plate increased the total mass diffusion transfer between two materials.

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Stress-assisted diffusion and the modified Fick law

Piekarski S.

Journal of Technical Physics

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2005

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Vol. 46, no 1

3-7

EN

It can be observed that the equation for "stress-assisted diffusion" applied by Shewmon (P.G. Shewmon, Diffusion in solids, McGraw-Hill, 1963) is simply the Einstein-Smoluchowski equation. In turn, for a constant temperature field, the modified Fick law (introduced in: S. Piekarski, On the modified Fick law and its potential applications, J. Tech. Phys., 44, 2, 125-131, 2003) reduces to the Einstein-Smoluchowski equation. Therefore, the solutions of the modified Fick law can be adopted to the problems considered by Shewmon. In this paper, the problems of diffusion and thermodiffusion in the strain fields of dislocations (screw and edge) are considered and new solutions are briefly discussed.

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On diffusion and thermodiffusion in a gravity field

Piekarski S.

Journal of Technical Physics

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2003

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Vol. 44, no 3

329-337

EN

The modified Fick law has been introduced in the paper: S. Piekarski, On the modified Fick law and its potential applications (J. Tech. Phys., 44, 2, 125-131, 2003). The first purpose of the present paper is to give a simpler "derivation" of the modified Fick law than that originally presented. Namely, it can be introduced as a particular case of the Wojnar equation (R. Wojnar, "Nonlinear heat equation and thermodiffusion", p. 296, Eq. (2.1), Rep. on Math. Phys., No 1/2, Vol. 46, 2000). The third equation discussed is the Einstein-Smoluchowski equation. All equations mentioned above, contain a potential for the force, acting on the diffusing matter. The important fact is that, for isothermal conditions, all the equations mentioned above are identical. In this article we try to describe the effects of the constant gravitational field on the diffusion processes. We propose an explicit form of the potential for which the equilibrium concentration profiles are consistent with the experimental results. We compare shortly our results with two models of the diffusion processes in a gravitational field described in Huang's book [8] as well as with other opinions concerning this subject. As an example of technological application of the presented theory, the diffusion of the atomic hydrogen in fluid iron is proposed.