A sphere of radius Ro is brought into contact with a copious amount of air. Assume that the material in the sphere is soluble in air, that the rate of dissolution of the solid is controlled by diffusion of the solu in a stagnant film, and that the density of the solute at the surface of the sphere is pAo. Determine the mass concentration profile of the solute along the stagnant film, as well as the mass diffusive flux, considering each of the following cases: A) The stagnant film has a thickness R1 and the mass concentration outside the film is pA1 B) What is a free diffusion process.

A sphere of radius Ro is brought into contact with a copious amount of air. Assume that the material in the sphere is soluble in air, that the rate of dissolution of the solid is controlled by diffusion of the solu in a stagnant film, and that the density of the solute at the surface of the sphere is pAo. Determine the mass concentration profile of the solute along the stagnant film, as well as the mass diffusive flux, considering each of the following cases: A) The stagnant film has a thickness R1 and the mass concentration outside the film is pA1 B) What is a free diffusion process.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.29P

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