Slides _ 8
Unsteady-state diffusion in
Semi-infinite solid means mathematically a region that has a
single boundary surface and extend to infinity in one
Mass Transfer _ lecture
Slides _ 7
Mass diffusion Equations
To generalize the derivation we are going to derive the general
diffusion equation which includes the spatial and time variable. On
other words, the derived eq
Slides _ 11
Re < 2100
W/DAB L < 70 gases
mass transfer data
follow rod like flow
* Interface means between wall and gas stream.
CA: exit conc.
CA0: inlet conc.
CAi: interface* conc.
Slides _ 10
Convective Mass Transfer
Exact solution(Blausius or Similarity
Hydrodynamic Solution _ similarity solution
The hydrodynamic solution follows the method of Blasius;
Define a stream function
Slides _ 13
How can we predict the rate of mass transfer?
We can predict the rate of mass transfer by using the
1. Ficks law (microscopic approach)
good for diffusion dominated problems