H. Scott Fogler - Vennema Professor of Chemical Engineering, University of Michigan, Ann Arbour, MI
There has recently been a major focus on the use of micro-reactors because of their high surface areas for excellent temperature control and safety. Because of the small size of these micro channels, the flow is most always laminar and therefore the plug flow assumption commonly used in reactor modeling cannot be used.
Consequently, for micro-reactors, as well as with many full-scale industrial tubular reactors, we must consider both axial and radial gradients, which requires the solution of the coupled partial differential equations (PDEs) for energy, mass and momentum.
Previously an analysis of such reaction systems was not usually carried out in graduate and undergraduate courses because of the inordinate amount of time required to write and debug large computer programs to obtain a numerical solution. However, we have now the capability to develop and easily solve the model equations in both these courses because of development of software tools such as COMSOL Multiphysics to solve PDEs.