numerical study of unsteady flow of gas through a porous medium by means of chebyshev pseudo-spectral method

Unsteady ow of gas through a porous medium is a strongly nonlinear ordinary di erential equation on semi-in nite interval. in this paper, we have applied the pseudo-spectral collocation method with a positive scaling factor to solve unsteady ow of gas through a porous medium. the method reduces the solution of this problem to the solution of a system of nonlinear algebraic equations. the arising system is solved by newton's method. to con rm the accuracy and eciency of the presented scheme, we are compared the obtained numerical results with some well-known results. results showed a very good agreement between results of presented scheme and the numerical solutions.