1. The problem statement, all variables and given/known data i want to use finite difference methodolgyto determine the steady-state potential flow field in a two dimensional duct using a square mesh and get epsi at every grid node and graph the stream lines...any suggestions ? 2. Relevant equations i've got an equation epsi(i,j) =1/4* epsi(i+1,j) + epsi(i-1,j) + epsi(i,j+1) + epsi(i,j-1) 3. The attempt at a solution i have the boundary conditions at the entrance anf exit and the button and top of the duct ... how can i attach a file to show you the problem ?