Question

13. In 1920, Professor August Krogh won a Nobel prize for his early mass-transfer study of oxygen transport in human tissue. By considering a tissue cylinder surrounding each blood vessel, he proposed the diffusion of oxygen away from the blood vessel into the annular tissue was accompanied by a zero-order reaction, Rx = -m, where m is a constant. This reaction was necessary to explain the metabolic consumption of the oxygen to produce carbon dioxide. a. Draw a picture of the physical process Select a coordinate system to describe this diffusion process. List at least five reasonable assumptions for the mass-transfer process. b. Write and simply the general differential equation for mass transfer in terms of the diffusive flux c. Rewrite the equation by applying Fick's Law.to yield a differential equation that could be solved to determine the concentration oxygen as a function of r. (you are not required to solve it)

Answer 1

sol a R - Blood vessel Assumption :- steady state → No convection → One directional diffusion Zero order reaction only oxygen is diffusing b . Fluxe in - Flux out Flux out - Reae" = 15 JA m 2mLdr so JAl-Talotar- J. 2002), -J: 2724 Joly- Jelutar from fick's lewe (roda al vocal) = mody 2 Irlmdr etde meda I= - DAB dCA dr ( Wow DAR d Irdea dr dr =m.o DAB Ane