Many physical phenomena, such as fluid flow, heat conduction and semiconductor growth include a diffusion process. The action of the diffusion is a continuous process that has and increasing effect with time and typically manifests itself as a spreading and smoothing of the original distribution.
In this demonstration, the simplest explicit Finite Difference Method is used as a means for solving a general diffusion problem. The demonstration uses Microsoft Excel, a spreadsheet. The Excel program can be downloaded from diff_FDM.xls .
A method for invese diffusion (ie going backwards in time) is deonstrated on the following spreadsheet invdiff.xls .