A liquid diffuses through a porous membrane of thickness L. If the concentration c(x,t) is maintained at c1 on the x=0 side of the membrane and c2 on the x=L side of the membrane, determine c(x,t) on the membrane. Assume that there is no liquid in the membrane initially and the Dliquid = D. Simplify the solution when the diffusion length is larger than 'L'.
Attempted this problem with trigonometric series solution but couldn't derive the equation.